Hello folks! Been a while ;-)

Have an issue going on that I have a feeling if I get to it quickly might resolve. Ok...I will try to desribe the issue the best I can. Let me start by saying, this DOES NOT happen while driving at low speeds such as in town driving...never. The car runs beautifully.

So, the last two times I have hit the highway, as I start getting up to speed (50-60mph) the rear end of my car starts to make a sound. It is almost like the sound of when something is wrong with the pavement and not the car. Like when you hit a stretch of highway that when your tires go over it it makes like a "clunk, clunk, clunk" sound and then goes away when you hit a better section of pavement. However it is not really a "clunk" in dramastic terms but a slight variation on that sound.

I know this stretch of highway well and it has never happened before. Here is the crazy part - each time it has happened, after the car warms up (lets say 5 - 7 minutes) it goes away and does not return. Craziest thing I have come across with this car. However, this is not normal so I started thinking about a few things it could be. The first thought that comes to mind would be the propshaft in the middle/rear of the car. Maybe it needs some WD-40 or some grease shot in with a needle? Next thing that comes to mind in maybe I need to fill the differential up with some oil? Granted, that should be a check at maybe 65k but my car only has about 30k on it - however that still means the last time it was checked was in 2002 when the car was made and maybe some evaporation has happened in there?

Anyhow...that is it and my possible thoughts. I would like to hear what you guys think and if you have any other things I should check please chime in. I would have to take it to a shop to get both done as I don't have a lift and I am too old to crawl under my car and try to work out that differential bolt and then try to pump out old fluid and put in new. With my car I actually tell my mechanic what to do and the procedures and they just do it since some of our stuff is that "filled for life" bullshit! ;-)

Thanks for reading and any and all comments welcome!

Cheers and peace out,

daddylogan

 

daddy logan, what you are describing sounds a lot like the prop shaft bearing starting to go. You can get some termaline grease and a needle attachment and squirt some grease into the bearing. That should resolve the noise. If it does, then you have proven what will need replace in the near future. if it continues, then I would move on to the differential lube check

 

Hi Chris!!!

That was quick...thank you. Going to attach a pic of my propshaft. At what points should I squirt the grease in at? Oh...also if I fill the differential shoudl I use Red Line 75w 140 High Performance Gear Oil? I think that is what I used in my transfer case oil change.

Thanks Bud!!!

peace out,
daddylogan

 

https://www.jaguarforums.com/forum/x...ring-faq-9853/

As for differential, yes 30,000 miles but lots of years. Wouldn't hurt at all to change it. I did mine when I bought it and was rather surprised how crappy the oil looked as well as it was low. I personally prefer Royal Purple which is what I used.

 

daddylogan, for ease, I would go after the 2-10-6 o'clock positions. That will make it as easy as possible, yet get around the bearing as much as possible. The trick wil be geting the needle under the rubber seal. But, a small flat blade will help with that.

 

Hey Dell-

Long time brother. Thanks for chiming in and the link. I have the mechanics all clued in on what to do.

One other question. How many ml of Gear Oil does the differential take assuming it is empty? Also do yoou fill until it drips out? I have read somewhere that people fill it until it flows out and then suck back out a few ml. I am not clear on that on to how you know when enough is in there and if overfilling may cause harm.

Thanks!

peace out,
daddylogan

 

I have a suction/pump unit. I suctioned the differential fluid out (and moved my inserted tube around a bunch) to ensure I got as much as possible out. Then I filled with Royal Purple (my preference) fluid just until it leaked out of the removed plug hole. Hurriedly screwed back in the plug.

 

Thank you Dell....unfortunately where I live I do not have access to Red Line or Royal unless I order it and my appointment at the shop is Monday. However at a NAPA I found Valvoline FlexFill Full Synthetic SAE 75W-140 Gear Oil 1 QT Pouches and they meet the M2C - 192A specs. So I will need 2 pouches of that to get a complete fill. The pouches are pretty cool as you are able to squeeze the oil with the flexable bag right into the fill hole!

peace out,

daddylogan

 

Well Redline is just their suggestion. As long as it meets the published specs you're good. As I mentioned, I use Royal Purple which meets specs.

 

daddylogan, the issue with refilling the rear differential too much is if the gear lube gets too much on the ring gear, it will cause it to froth up. This now allows air to get in contact with the metal surface. This causes the metal gears to now rub on each other inside of getting an oil wedge locked in there providing the lubrication needs. Metal rubbing on metal is a bad thing.

 

Hey Chris-

Then how does one know the starting point for sure? I know Dell's chart above said to fill to 1.15L (1150ML) assuming empty - but what if the old oil is to thick to suck out with a syringe/pump and some is left behind? Should I have the mechanic fill until overflow and then have them remove an "x" amount of ML before tightening down the plug?

peace out,
daddylogan?

 

daddylogan, you keep the car level (especially side to side), the hole should prevent that from happening. Fill till the fluid starts flowing back out. Let it slow to a slow dribble, then install the plug.

 

Thank you Chris!!! You and Dell always have been curtious in providing sound information. It is appreciated by many. Cheers

peace out,

daddylogan