2004 XJ VDP Oil Change FAQ
Senior Member
Joined: Feb 2015
Posts: 113
Likes: 17
From: palm springs
Just changed my oil after 4 years and 18K miles
Using the OEM factory filter and only driving a very small amount over a 4 year period. I changed my oil on my 2007 XJR. I live in the most extreme heat in the country and It was originally changed under warranty at the dealership with 5W-30 Mobil 1 back in 2011. I sent my oil out to be analyzed at Titan Labs in Denver Co. The results came back that the oil was still good, almost No trace elements from breakdown of any internal engine parts and the car has 95K miles on the odometer. I am the second owner and it had been serviced at the dealer its entire life. So, people before you go out and spend ridiculous amounts of money on changing your oil CONSTANTLY, have it analyzed first. I went to Walmart and bought 30.00 worth of FULL synthetic OEM Mobil 1 5W-30 and went to the dealer and bought the OEM filter for 14.00 and for 44.00, I did my own oil change. The test results also came back that the viscosity of the oil had not broken down and was told I could keep driving it and when it had another 10K miles send more in for another analysis. So, you guys can keep wasting your money all you want but I have read articles where people have gone 30K miles on a synthetic oil change from Mobil 1 and have had NO issues what so ever. Changing oil in the old days was a must because they had paraffin in them and not so much detergent ( regular motor oil that is) so any heat exchange would cause the oils to break down very quickly. If you use full synthetic oil as the Manufacture suggests, you will not have to worry about engine oil breaking down. Just make sure you keep the oil levels up. I don't think I have had to put but a quart in, in total in the 4 years of owning the car.
Veteran Member
Joined: Jun 2010
Posts: 2,330
Likes: 544
From: Spring, TX
I take mine down the street to Pepboys. They let you dump it for free (probably because they'll end up reusing it on some poor jerk's car). I think most auto parts stores will dispose of it for you.
Joined: Mar 2012
Posts: 4,759
Likes: 1,435
From: Hazlet Township, NJ
Just changed the oil on my 04 XJR today. 6.5 qts is a tad above midway between min and max dots on dipstick.
I'll verify in the morning but I'm presuming I'm putting that remaining 0.5 qt in the crankcase. Also, I tried using a Bosch oil filter and when tightening it simply stopped turning about 1/2 turn.
Didn't want to force the filter any further on.
Needless to say when I started the car I noticed oil was starting to weep past the seal. Changed out the Bosch for a Purolator Pure One oil filter.
The Bosch must have had a defect as I was able to turn the pure one oil filter to the recommended 3/4 to 1 turn after gasket makes contact.
Never had issues before with Bosch...
Senior Member
Joined: May 2008
Posts: 184
Likes: 38
From: SoCal
The more severe your driving conditions are, more frequent oil changes are needed. All my 3 jags I change at max 5K miles. I Make a point to do an early change before the summer months. The weak link in the oil change interval, is the cheap oil filters. Most don't perform as expected past 5K mile due to their one size fits all. Their are a few that are advertised to operate to 15k miles. You should buy the extended use oil filters if you plan oil changes beyond 5k miles.
Make sure you use a new oil drain plug washer at ea oil change. There are a single use compressible Al washer.
PS...
Don't use synthetic blend oil. It's chief make up is recycled oil. Use all synthetic oil or conventional oil.
Make sure you use a new oil drain plug washer at ea oil change. There are a single use compressible Al washer.
PS...
Don't use synthetic blend oil. It's chief make up is recycled oil. Use all synthetic oil or conventional oil.
Last edited by mberman; Nov 6, 2017 at 12:17 PM.
Junior Member
Joined: Oct 2013
Posts: 3
Likes: 1
From: Aston, PA
One important thing that you forgot to mention. These cars are equipped with air suspension. Whenever you get under the car, make DOUBLE sure if the air ride collapses it has enough room to colapse without crashing the owner. Nobody thinks of this. My airstrut failed and I assure you that car goes right to the ground!
Senior Member
Joined: Nov 2010
Posts: 106
Likes: 8
From: California
One important thing that you forgot to mention. These cars are equipped with air suspension. Whenever you get under the car, make DOUBLE sure if the air ride collapses it has enough room to colapse without crashing the owner. Nobody thinks of this. My airstrut failed and I assure you that car goes right to the ground!
And previously when dealer or a mechanic changed my oil they charged for a seal. I presume when the oil drain plug is removed there is a seal on it that must be replaced? Didn't see that mentioned anywhere in the thread.
Junior Member
Joined: Oct 2013
Posts: 3
Likes: 1
From: Aston, PA
Any reason why the car can't be raised with two jacks and jack stands? Then don't have to worry about air suspension.
And previously when dealer or a mechanic changed my oil they charged for a seal. I presume when the oil drain plug is removed there is a seal on it that must be replaced? Didn't see that mentioned anywhere in the thread.
And previously when dealer or a mechanic changed my oil they charged for a seal. I presume when the oil drain plug is removed there is a seal on it that must be replaced? Didn't see that mentioned anywhere in the thread.
Veteran Member
Joined: Sep 2016
Posts: 3,481
Likes: 879
From: Stow Ohio
XJPur asked;
Any reason why the car can't be raised with two jacks and jack stands? Then don't have to worry about air suspension.
Not any reason at all, used two or four with stands on mine for various jobs.
A lift would be a lot better, but cost always seems to be a limiting factor.
Any reason why the car can't be raised with two jacks and jack stands? Then don't have to worry about air suspension.
Not any reason at all, used two or four with stands on mine for various jobs.
A lift would be a lot better, but cost always seems to be a limiting factor.
Junior Member
Joined: Jul 2020
Posts: 15
Likes: 2
From: Saint Augustine, Florida, USA
A few extra notes and corrections.
I read this thread with great interest when it came time to do the first oil change in my new-to-me 2004 XJR. A few notes and corrections:
1) There definitely ARE two Phillips head screws in deep recesses toward the front end of the splash shield. [At least, there were when the vehicle was manufactured.] If you look at the shield, as shown in the second picture in the thread, you see three widely spaced silver rivets, with two holes evenly spaced between the rivets. Those rivets hold a metal bracket on the underside (actually topside, if you know what I mean) that runs the width of the shield; the two holes are access ports to reach Phillips head screws that attach the bracket (and hence the shield) to the underbody. The screws are deep in those holes. They could be an absolute bear to extract and insert, and probably unnecessary, and I suspect in many of our cars somewhere along the line somebody simply didn't bother replacing them. I ended up using a powerful magnet on the shaft of the screwdriver to hold the screw on the tip while poking it as deep as it needed to go in order to engage the threads. The old tape trick would probably work also.
2) The discussion about oil filter change interval, and old filters being "better" than fresh ones. I know quite a bit about this from GM. It has nothing to do with oil saturation; it has everything to do with dirt saturation. What happens with oil filters is that the microscopic holes in the filter medium are of varying sizes, some relatively big, big enough to let particles flow through. As particulates start to build up in the filter, those large holes tend to accumulate crud around the edges, narrowing the hole, eventually to the point that the opening is no longer large enough to allow particles through. So it is fair to say a filter with some age on it is more efficient at filtering out particles; it will indeed do a better job of that. The downside is that as the bigger holes are being plugged, so are the smaller ones, hence it starts to take more pressure to force the oil through. Eventually the pressure required will open the bypass valve, so that the motor is not starved for oil. There are a lot of variables involved so it's hard to pinpoint for any given car, driver, driving condition and driving environment exactly how many miles the filter will be good for, and even harder to pinpoint the not-so-sweet spot where the increased particulate filtering efficiency of the filter begins to be outweighed by the overall resistance to oil flow. If you change oil every 3k miles, you may well be slightly better off changing the filter every other change or third change. If you take the mileage all the way out to the 10k manufacturer allowance, I would think you'd be smart to change the filter at each (extended) change.
3. I appreciated the discourse on ramps. For some reason, the XJR has a tendency to push the ramps instead of mounting them. I'm not sure it's a clearance issue, because even with small wood blocks placed before the ramp section, the car still plowed rather than mounted when it reached the ramp section. I ended up having to use 2x4s to brace the rears of the ramps so they couldn't move backwards. FWIW I use the plastic Rhino ramps, so maybe it's a lack of ground friction, but my big BMW, Audi and Touareg have not had this issue. [Also, great tip on remembering to use jack stands while under an air suspension car.]
4. I definitely lucked out with this XJR. The underside, especially under the shield, was clean as a whistle. No rust, no debris, all the bolts and nuts came out easily. I do not think that experience is typical, and would recommend at least using anti-seize on all nuts, bolts and screws when reinstalling the shield.
5. Even though the pan plug is easy to get to once the shield is removed, I shall put in a plug (pun intended) for replacing the bolt with a Stahlbus valve. Very secure mechanism, the cap makes sure the oil stays put even if the valve were to fail, and the drain procedure is far neater. You can even drain the oil directly into your jug for recycling, without bothering with an oil pan.
Tigertank84
2004 XJR 47k
1) There definitely ARE two Phillips head screws in deep recesses toward the front end of the splash shield. [At least, there were when the vehicle was manufactured.] If you look at the shield, as shown in the second picture in the thread, you see three widely spaced silver rivets, with two holes evenly spaced between the rivets. Those rivets hold a metal bracket on the underside (actually topside, if you know what I mean) that runs the width of the shield; the two holes are access ports to reach Phillips head screws that attach the bracket (and hence the shield) to the underbody. The screws are deep in those holes. They could be an absolute bear to extract and insert, and probably unnecessary, and I suspect in many of our cars somewhere along the line somebody simply didn't bother replacing them. I ended up using a powerful magnet on the shaft of the screwdriver to hold the screw on the tip while poking it as deep as it needed to go in order to engage the threads. The old tape trick would probably work also.
2) The discussion about oil filter change interval, and old filters being "better" than fresh ones. I know quite a bit about this from GM. It has nothing to do with oil saturation; it has everything to do with dirt saturation. What happens with oil filters is that the microscopic holes in the filter medium are of varying sizes, some relatively big, big enough to let particles flow through. As particulates start to build up in the filter, those large holes tend to accumulate crud around the edges, narrowing the hole, eventually to the point that the opening is no longer large enough to allow particles through. So it is fair to say a filter with some age on it is more efficient at filtering out particles; it will indeed do a better job of that. The downside is that as the bigger holes are being plugged, so are the smaller ones, hence it starts to take more pressure to force the oil through. Eventually the pressure required will open the bypass valve, so that the motor is not starved for oil. There are a lot of variables involved so it's hard to pinpoint for any given car, driver, driving condition and driving environment exactly how many miles the filter will be good for, and even harder to pinpoint the not-so-sweet spot where the increased particulate filtering efficiency of the filter begins to be outweighed by the overall resistance to oil flow. If you change oil every 3k miles, you may well be slightly better off changing the filter every other change or third change. If you take the mileage all the way out to the 10k manufacturer allowance, I would think you'd be smart to change the filter at each (extended) change.
3. I appreciated the discourse on ramps. For some reason, the XJR has a tendency to push the ramps instead of mounting them. I'm not sure it's a clearance issue, because even with small wood blocks placed before the ramp section, the car still plowed rather than mounted when it reached the ramp section. I ended up having to use 2x4s to brace the rears of the ramps so they couldn't move backwards. FWIW I use the plastic Rhino ramps, so maybe it's a lack of ground friction, but my big BMW, Audi and Touareg have not had this issue. [Also, great tip on remembering to use jack stands while under an air suspension car.]
4. I definitely lucked out with this XJR. The underside, especially under the shield, was clean as a whistle. No rust, no debris, all the bolts and nuts came out easily. I do not think that experience is typical, and would recommend at least using anti-seize on all nuts, bolts and screws when reinstalling the shield.
5. Even though the pan plug is easy to get to once the shield is removed, I shall put in a plug (pun intended) for replacing the bolt with a Stahlbus valve. Very secure mechanism, the cap makes sure the oil stays put even if the valve were to fail, and the drain procedure is far neater. You can even drain the oil directly into your jug for recycling, without bothering with an oil pan.
Tigertank84
2004 XJR 47k
Member
Joined: Jan 2021
Posts: 42
Likes: 14
From: Abilene, Texas
So what do you all do with the old motor oil? Recycler or something like that? if so what does it cost to dispose of it?
I took mine to where they brew LONE STAR BEER. I noticed they taste almost identical.
I took mine to where they brew LONE STAR BEER. I noticed they taste almost identical.
Junior Member
Joined: Jul 2023
Posts: 15
Likes: 5
From: Port Orchard, Washington USA
Thanks to All Contributors!
I read this thread with great interest when it came time to do the first oil change in my new-to-me 2004 XJR. A few notes and corrections:
1) There definitely ARE two Phillips head screws in deep recesses toward the front end of the splash shield. [At least, there were when the vehicle was manufactured.] If you look at the shield, as shown in the second picture in the thread, you see three widely spaced silver rivets, with two holes evenly spaced between the rivets. Those rivets hold a metal bracket on the underside (actually topside, if you know what I mean) that runs the width of the shield; the two holes are access ports to reach Phillips head screws that attach the bracket (and hence the shield) to the underbody. The screws are deep in those holes. They could be an absolute bear to extract and insert, and probably unnecessary, and I suspect in many of our cars somewhere along the line somebody simply didn't bother replacing them. I ended up using a powerful magnet on the shaft of the screwdriver to hold the screw on the tip while poking it as deep as it needed to go in order to engage the threads. The old tape trick would probably work also.
2) The discussion about oil filter change interval, and old filters being "better" than fresh ones. I know quite a bit about this from GM. It has nothing to do with oil saturation; it has everything to do with dirt saturation. What happens with oil filters is that the microscopic holes in the filter medium are of varying sizes, some relatively big, big enough to let particles flow through. As particulates start to build up in the filter, those large holes tend to accumulate crud around the edges, narrowing the hole, eventually to the point that the opening is no longer large enough to allow particles through. So it is fair to say a filter with some age on it is more efficient at filtering out particles; it will indeed do a better job of that. The downside is that as the bigger holes are being plugged, so are the smaller ones, hence it starts to take more pressure to force the oil through. Eventually the pressure required will open the bypass valve, so that the motor is not starved for oil. There are a lot of variables involved so it's hard to pinpoint for any given car, driver, driving condition and driving environment exactly how many miles the filter will be good for, and even harder to pinpoint the not-so-sweet spot where the increased particulate filtering efficiency of the filter begins to be outweighed by the overall resistance to oil flow. If you change oil every 3k miles, you may well be slightly better off changing the filter every other change or third change. If you take the mileage all the way out to the 10k manufacturer allowance, I would think you'd be smart to change the filter at each (extended) change.
3. I appreciated the discourse on ramps. For some reason, the XJR has a tendency to push the ramps instead of mounting them. I'm not sure it's a clearance issue, because even with small wood blocks placed before the ramp section, the car still plowed rather than mounted when it reached the ramp section. I ended up having to use 2x4s to brace the rears of the ramps so they couldn't move backwards. FWIW I use the plastic Rhino ramps, so maybe it's a lack of ground friction, but my big BMW, Audi and Touareg have not had this issue. [Also, great tip on remembering to use jack stands while under an air suspension car.]
4. I definitely lucked out with this XJR. The underside, especially under the shield, was clean as a whistle. No rust, no debris, all the bolts and nuts came out easily. I do not think that experience is typical, and would recommend at least using anti-seize on all nuts, bolts and screws when reinstalling the shield.
5. Even though the pan plug is easy to get to once the shield is removed, I shall put in a plug (pun intended) for replacing the bolt with a Stahlbus valve. Very secure mechanism, the cap makes sure the oil stays put even if the valve were to fail, and the drain procedure is far neater. You can even drain the oil directly into your jug for recycling, without bothering with an oil pan.
Tigertank84
2004 XJR 47k
1) There definitely ARE two Phillips head screws in deep recesses toward the front end of the splash shield. [At least, there were when the vehicle was manufactured.] If you look at the shield, as shown in the second picture in the thread, you see three widely spaced silver rivets, with two holes evenly spaced between the rivets. Those rivets hold a metal bracket on the underside (actually topside, if you know what I mean) that runs the width of the shield; the two holes are access ports to reach Phillips head screws that attach the bracket (and hence the shield) to the underbody. The screws are deep in those holes. They could be an absolute bear to extract and insert, and probably unnecessary, and I suspect in many of our cars somewhere along the line somebody simply didn't bother replacing them. I ended up using a powerful magnet on the shaft of the screwdriver to hold the screw on the tip while poking it as deep as it needed to go in order to engage the threads. The old tape trick would probably work also.
2) The discussion about oil filter change interval, and old filters being "better" than fresh ones. I know quite a bit about this from GM. It has nothing to do with oil saturation; it has everything to do with dirt saturation. What happens with oil filters is that the microscopic holes in the filter medium are of varying sizes, some relatively big, big enough to let particles flow through. As particulates start to build up in the filter, those large holes tend to accumulate crud around the edges, narrowing the hole, eventually to the point that the opening is no longer large enough to allow particles through. So it is fair to say a filter with some age on it is more efficient at filtering out particles; it will indeed do a better job of that. The downside is that as the bigger holes are being plugged, so are the smaller ones, hence it starts to take more pressure to force the oil through. Eventually the pressure required will open the bypass valve, so that the motor is not starved for oil. There are a lot of variables involved so it's hard to pinpoint for any given car, driver, driving condition and driving environment exactly how many miles the filter will be good for, and even harder to pinpoint the not-so-sweet spot where the increased particulate filtering efficiency of the filter begins to be outweighed by the overall resistance to oil flow. If you change oil every 3k miles, you may well be slightly better off changing the filter every other change or third change. If you take the mileage all the way out to the 10k manufacturer allowance, I would think you'd be smart to change the filter at each (extended) change.
3. I appreciated the discourse on ramps. For some reason, the XJR has a tendency to push the ramps instead of mounting them. I'm not sure it's a clearance issue, because even with small wood blocks placed before the ramp section, the car still plowed rather than mounted when it reached the ramp section. I ended up having to use 2x4s to brace the rears of the ramps so they couldn't move backwards. FWIW I use the plastic Rhino ramps, so maybe it's a lack of ground friction, but my big BMW, Audi and Touareg have not had this issue. [Also, great tip on remembering to use jack stands while under an air suspension car.]
4. I definitely lucked out with this XJR. The underside, especially under the shield, was clean as a whistle. No rust, no debris, all the bolts and nuts came out easily. I do not think that experience is typical, and would recommend at least using anti-seize on all nuts, bolts and screws when reinstalling the shield.
5. Even though the pan plug is easy to get to once the shield is removed, I shall put in a plug (pun intended) for replacing the bolt with a Stahlbus valve. Very secure mechanism, the cap makes sure the oil stays put even if the valve were to fail, and the drain procedure is far neater. You can even drain the oil directly into your jug for recycling, without bothering with an oil pan.
Tigertank84
2004 XJR 47k
Shout out to everyone who started this thread and have continued to engage with their collective knowledge. It was all indispensable as I tackled my first oil change on my 2006 XJ8 x350. (First DIY oil change EVER, actually.) A couple notes from my experience today:
1) Firstly, echoing an earlier post about the Rhino Ramps just getting pushed around. Took me multiple attempts and finally had to wedge them against the edge of my slab to get up top. I will be blocking them against some lumber braces next time, or just build my own that are longer, more gradual, and taller. Tight fit under there!
2) That single piece undercarriage cover: Oy. Getting that sucker on/off was the bulk of my time. Luckily with all the notes from this thread I knew what to look for. The 17-years before my turn as owner haven’t been kind to the cover, snd clearly my predecessors and their mechanics didn’t think much of it. Of the 6-8 original mounting points I found only THREE were still in use, and the two midpoint posts weren’t among them. Meaning all the bumps and sag were supported by just two mounts at the grill, one at the rear, and partial credit to the other one in back that was just barely hanging on. Secured the post mounts and added larger washers to the other points to hopefully prolong the integrity of the plastic around all the mounts.
May talk to a mechanic about doing a cutout around the filter/drain plug, but instead of leaving it open installing a secondary cover solution with a hinge/latch or just its own set of mounts for simpler access. I think that and the Stahlbus valve would make the job much more routine.
All in all, very glad I decided to DIY this task. And am kicking myself for not having done it for all my cars. Oh well, never stop learning! Cheers!
Mitch
2006 XJ8 x350 “Roxanne”
Joined: Mar 2012
Posts: 4,759
Likes: 1,435
From: Hazlet Township, NJ
I read this thread with great interest when it came time to do the first oil change in my new-to-me 2004 XJR. A few notes and corrections:
1) There definitely ARE two Phillips head screws in deep recesses toward the front end of the splash shield. [At least, there were when the vehicle was manufactured.] If you look at the shield, as shown in the second picture in the thread, you see three widely spaced silver rivets, with two holes evenly spaced between the rivets. Those rivets hold a metal bracket on the underside (actually topside, if you know what I mean) that runs the width of the shield; the two holes are access ports to reach Phillips head screws that attach the bracket (and hence the shield) to the underbody. The screws are deep in those holes. They could be an absolute bear to extract and insert, and probably unnecessary, and I suspect in many of our cars somewhere along the line somebody simply didn't bother replacing them. I ended up using a powerful magnet on the shaft of the screwdriver to hold the screw on the tip while poking it as deep as it needed to go in order to engage the threads. The old tape trick would probably work also.
2) The discussion about oil filter change interval, and old filters being "better" than fresh ones. I know quite a bit about this from GM. It has nothing to do with oil saturation; it has everything to do with dirt saturation. What happens with oil filters is that the microscopic holes in the filter medium are of varying sizes, some relatively big, big enough to let particles flow through. As particulates start to build up in the filter, those large holes tend to accumulate crud around the edges, narrowing the hole, eventually to the point that the opening is no longer large enough to allow particles through. So it is fair to say a filter with some age on it is more efficient at filtering out particles; it will indeed do a better job of that. The downside is that as the bigger holes are being plugged, so are the smaller ones, hence it starts to take more pressure to force the oil through. Eventually the pressure required will open the bypass valve, so that the motor is not starved for oil. There are a lot of variables involved so it's hard to pinpoint for any given car, driver, driving condition and driving environment exactly how many miles the filter will be good for, and even harder to pinpoint the not-so-sweet spot where the increased particulate filtering efficiency of the filter begins to be outweighed by the overall resistance to oil flow. If you change oil every 3k miles, you may well be slightly better off changing the filter every other change or third change. If you take the mileage all the way out to the 10k manufacturer allowance, I would think you'd be smart to change the filter at each (extended) change.
3. I appreciated the discourse on ramps. For some reason, the XJR has a tendency to push the ramps instead of mounting them. I'm not sure it's a clearance issue, because even with small wood blocks placed before the ramp section, the car still plowed rather than mounted when it reached the ramp section. I ended up having to use 2x4s to brace the rears of the ramps so they couldn't move backwards. FWIW I use the plastic Rhino ramps, so maybe it's a lack of ground friction, but my big BMW, Audi and Touareg have not had this issue. [Also, great tip on remembering to use jack stands while under an air suspension car.]
4. I definitely lucked out with this XJR. The underside, especially under the shield, was clean as a whistle. No rust, no debris, all the bolts and nuts came out easily. I do not think that experience is typical, and would recommend at least using anti-seize on all nuts, bolts and screws when reinstalling the shield.
5. Even though the pan plug is easy to get to once the shield is removed, I shall put in a plug (pun intended) for replacing the bolt with a Stahlbus valve. Very secure mechanism, the cap makes sure the oil stays put even if the valve were to fail, and the drain procedure is far neater. You can even drain the oil directly into your jug for recycling, without bothering with an oil pan.
Tigertank84
2004 XJR 47k
1) There definitely ARE two Phillips head screws in deep recesses toward the front end of the splash shield. [At least, there were when the vehicle was manufactured.] If you look at the shield, as shown in the second picture in the thread, you see three widely spaced silver rivets, with two holes evenly spaced between the rivets. Those rivets hold a metal bracket on the underside (actually topside, if you know what I mean) that runs the width of the shield; the two holes are access ports to reach Phillips head screws that attach the bracket (and hence the shield) to the underbody. The screws are deep in those holes. They could be an absolute bear to extract and insert, and probably unnecessary, and I suspect in many of our cars somewhere along the line somebody simply didn't bother replacing them. I ended up using a powerful magnet on the shaft of the screwdriver to hold the screw on the tip while poking it as deep as it needed to go in order to engage the threads. The old tape trick would probably work also.
2) The discussion about oil filter change interval, and old filters being "better" than fresh ones. I know quite a bit about this from GM. It has nothing to do with oil saturation; it has everything to do with dirt saturation. What happens with oil filters is that the microscopic holes in the filter medium are of varying sizes, some relatively big, big enough to let particles flow through. As particulates start to build up in the filter, those large holes tend to accumulate crud around the edges, narrowing the hole, eventually to the point that the opening is no longer large enough to allow particles through. So it is fair to say a filter with some age on it is more efficient at filtering out particles; it will indeed do a better job of that. The downside is that as the bigger holes are being plugged, so are the smaller ones, hence it starts to take more pressure to force the oil through. Eventually the pressure required will open the bypass valve, so that the motor is not starved for oil. There are a lot of variables involved so it's hard to pinpoint for any given car, driver, driving condition and driving environment exactly how many miles the filter will be good for, and even harder to pinpoint the not-so-sweet spot where the increased particulate filtering efficiency of the filter begins to be outweighed by the overall resistance to oil flow. If you change oil every 3k miles, you may well be slightly better off changing the filter every other change or third change. If you take the mileage all the way out to the 10k manufacturer allowance, I would think you'd be smart to change the filter at each (extended) change.
3. I appreciated the discourse on ramps. For some reason, the XJR has a tendency to push the ramps instead of mounting them. I'm not sure it's a clearance issue, because even with small wood blocks placed before the ramp section, the car still plowed rather than mounted when it reached the ramp section. I ended up having to use 2x4s to brace the rears of the ramps so they couldn't move backwards. FWIW I use the plastic Rhino ramps, so maybe it's a lack of ground friction, but my big BMW, Audi and Touareg have not had this issue. [Also, great tip on remembering to use jack stands while under an air suspension car.]
4. I definitely lucked out with this XJR. The underside, especially under the shield, was clean as a whistle. No rust, no debris, all the bolts and nuts came out easily. I do not think that experience is typical, and would recommend at least using anti-seize on all nuts, bolts and screws when reinstalling the shield.
5. Even though the pan plug is easy to get to once the shield is removed, I shall put in a plug (pun intended) for replacing the bolt with a Stahlbus valve. Very secure mechanism, the cap makes sure the oil stays put even if the valve were to fail, and the drain procedure is far neater. You can even drain the oil directly into your jug for recycling, without bothering with an oil pan.
Tigertank84
2004 XJR 47k
Thanks
Junior Member
Joined: Jul 2023
Posts: 15
Likes: 5
From: Port Orchard, Washington USA
Mitch
2006 XJ8 x350
