I think I may try even Valvoline full synth 20W-50

 

If you're going for a 50 weight oil go for the lowest first number you can. Although unless you're in exceptionally hot weather, there should be no need for a 50 weight oil. Heavier does not mean better lubrication, often the reverse.

However, a clue to the oil use may be the overfilling. Engines will use more oil if they are overfull. Perhaps get the level correct and then see what happens before deviating from the recommended grades.

 

Another thought did your car originally run on Non-Synthetic? Mine did and I decided not to switch. I think you have to drain completely and not mix the two except in an emergency. Obviously, you need to change the oil more frequently with non, but we never drove it that much 10-12k/year now down to 5k, so I just changed it every 6 months and still do.

 

the non synth was drained and full synth Mobil 1 10w-40 was the new oil.
I do 2500mi/month. if I do not use full synth I have to change oil almost every month.

 

I note that your average temps there in Calgary are 19cF to 62cF thus according to the Jaguar chart recommendations you should be looking at -
10W/40
10W/50
5W/40
5W/50
Any of these in fully synthetic & a reputable brand should be suitable.
Here in Queensland (Australia) the states temps run from 15cF to 110cF & I have used 5W/40 (Shell ultimate fully Synthetic) for many years.
I also attach copy of Handbook page - Check/top up engine oil. Of particular note is the comments regarding the "M" mark on the dipstick & checking "cold or hot".
Might I suggest you fill up with one of the above suggestions & proceeds to carefully monitor & check your levels & consumption for say the next 3 months.

John Herbert

 

Whoops, you are in San Francisco where I believe temps are 50cF to 60cF.
We can thus include - 15W/40, 15W/50, 20W/40 & 20W/50.
With your apparent concerns regarding low viscosity oil & perhaps greater than expected oil consumption, your safe bet is probably 20W/50, your choice but I would be guided by the chart recommendations. Your current choice of 10W/40 is probably ok however.

John Herbert

 

I have decided to try Valvoline 20w-50 or Vavoline VR1 racing 20w-50 both full synth. Eventually VR1 would be better because it has zinc and Phosphor inside which is good for the AJ16 engine as aholbro1 kindly mentioned to me.
The weird thing is that if I read the specs from Valvoline they do not recommend to use VR1 for extended mileage on catalytic converters vehicles... may the small amount of minerals like Zinc and Phosphor damage the cats ?

 

Not weird, Valvoline happen to know what their taking about.
Cats do not like phosphorus.
Why use the racing oil, do you intend to use your car for that purpose, is it a racing engine ?

John Herbert

 

I note that the Shell Rotella T6 recommended by Aholbro1 actually has reduced levels of phosphorous according to the Shell brochure.

John Herbert

 

I'll go with the full synth Valvoline 20w-50 for the upcoming oil change.
thanks for all the hints

 

I used to use the Shell, but the last time I looked at a bottle I noticed that it was no longer certified for gasoline engines, just diesel. It use to be certified for both gas and diesel.

 

API CJ-4, CI-4 PLUS, CI-4, CH-4, SM, SL, SH; ACEA E9; Caterpillar
ECF-3, ECF-2; Cummins CES 20081; DDC 93K218; Ford WSS
M2C171-E; JASO DH-2, MA; Mack EO-O Premium Plus; MB Approval
228.31; Volvo VDS-4

per: http://rotella.shell.com/products/t6...6-brochure.pdf
"SH" is the preferred spec according to the owner's manual delivered with my X300.

My Story: Bought my first X300 with 63k miles on it in 2010. First oil change was to Valvoline 10W-30 SynPower. Exhibited what I'd call excessive oil consumption, though don't recall now how much make-up oil it took to get to 5k mi and the next change. Found Valvoline 20W-50 VR-1 racing oil to be the only readily locally available 50 wt. Came home, researched on the interweb and found (the following memories are foggy and may not reflect reality) VR-1 had levels of phosphor and such that were common in engine oils of the early-mid-90's era when the engine was produced but which had been deleted from modern oils. Read somewhere that I deemed credible that the AJ-16 would profit from such phosphor levels. So I switched to that.

However, it was winter...we had a few mornings with temps in the teens (Deg F) and the cranking was noticeably slower and there was significant noise on startup for a few minutes.

Talked to Motorcarman, who indicated they used to use heavy duty 15W-40 in the X300 when he was at the dealership.

3rd oil change was to Rotella T6 5W-40 synthetic which I'd been using in my 7.3L Excursion. I reckon the car had 75k-80k on it, then. Continued 5k oil changes for a year or two after that, have subsequently switched to 7.5k change interval. Car now sports 228K. Kid's 96 has been on T6 since we acquired it at 104K. Just noticed this weekend he's slipped by the change interval on me - has 10k on this bit, so we'll be changing it next weekend. Now at 128K or so. The Exc. has 240k. No oil-related problems on any of them.

I think it doesn't matter so much what you use, so long as you keep the level in-range (not so hard as the range has a 2-qt spread) and change it at regular intervals.

 

Maybe market differences? When I looked at the shell.ca brochure it no longer has any S designations, and that matches what I saw at the parts store.
https://www.shell.ca/en_ca/business-...l-sheet-en.pdf

 

I know this thread is about oil consumption, but has turned into a ‘what’s best?’ Oil thread. I live in a mild climate (0-35’C) and have an XJR - I use synthetic Castrol Edge 5W-40.

I went to do an oil change yesterday, took off the filter, but even with a 12” Crescent spanner I couldn’t undo the sump drain plug so I abandoned it - my mechanic has done it up very tight last time!
Having already drained the filter, the oil needed a top-up. It took over a litre, and the oil wasn’t even on the tip of the dipstick after running the engine to re-fill the filter, prior to top up. My car does now use some oil, I don’t know how much, but not very much. I know it is considered normal for some usage, and the handbook acknowledges this.
I am going on a 500 mile road trip next weekend, so I will pay close attention to oil use.

The car is certainly happier today with the sump filled to the upper level - it ran more smoothly at low revs pulling from traffic lights etc.

 

A 12" crescent spanner is not I believe a good mechanics "tool of choice"
Have your tried a 30mm socket & suitably long extension bar.
I concur with your oil choice, as probably noticed from my previous posts I am just over the ditch in Australia with similar temps. & have used Shell Helix Ultra 5W/40 with satisfactory results for many years.

John Herbert
(1996 XJR)

 

[QUOTE=Jagboi64;1860629]Maybe market differences? When I looked at the shell.ca brochure it no longer has any S designations, and that matches what I saw at the parts store.

I believe you are correct, you are quoting from a 2017 technical sheet, Aholbro1 is quoting from a 2013 sheet.
The composition of Shell Rotella T6 has obviously been updated & in fact no longer has any petrol engine approvals, it only has the very latest "heavy duty diesel" approvals. Note API now CK-4, introduced 2017.
With this in mind I would draw your attention to comments by Amsoil - " The American Petroleum Institute (API) publishes its “C” category of specification for diesel oil (currently CK-4) and its “S” category for gasoline motor oil (currently SN). It’s common for today’s diesel engine oils to carry both the API CK-4 and API SN specifications. Though they’re truly designed for diesel applications, they can be used in gasoline applications for motorists who want to use one oil in all applications. If the diesel oil carries both specs, the oil is safe to use in diesel and gasoline applications. If the diesel oil does not carry the “S” category, AMSOIL strongly recommends against using it in gasoline applications."

John Herbert
(1996 XJR)

 

[QUOTE=AL NZ;1860801]

I went to do an oil change yesterday, took off the filter, but even with a 12” Crescent spanner I couldn’t undo the sump drain plug so I abandoned it - my mechanic has done it up very tight last time! ‘End of quote’

When I went to do an oil change on my first ‘40 (2.9) the sump plug had already been stripped and replaced with a larger one. This was so tight I had to lower the car onto the breaker bar and use the weight of the car to break the plug free. This was back in about 2002/3

 

Well...crap! Shell, if you change the formulation, rename the damn stuff. Isn't T6 anymore, now is it? sTrictly speaking.
https://forums.nasioc.com/forums/sho...60&postcount=8

Looks like I'll have to search out a new standard, although "New T6" appears ok to continue in the Excursion - I can't help thinking this is a "new Coke" type move, but whatever...

Thanks for straightening me out, John and Jagboi

 

Just completed an oil & filter change in the lad's '96. I think I've found my new, common, dual-spec oil: Chevron Delo 400
le - Delo 400 LE Synthetic 5W-40 | Chevron Lubricants
I've got a gallon of T6 left on the shelf, so I'll likely buy 3 more gallons of it to complete the next 15 qt Excursion oil change, then it's "Sayonara Shell!"

Surprisingly, the Delo was a bit cheaper than the T-6. Guess I wasn't looking hard enough when I thought T-6 was the cheapest full-syn meeting the necessary specs for my equipment.

 

turned out that the main reason for oil consumption is related to leak.
there is a leak from the oil pan gasket. The problem did not come out when I was using normal oil (not full synth).
Any mechanics will charge 7 hours of labor for this that's so much money.
There is also a valve cover gasket leak and I will address it shortly.
Anyway with the Valvoline 20w50 the engine seems running smoother, I do not know why, compared to previous Mobil 1 10W40. Also the Mobil 1 became really very dark almost immediately. This Valvoline it's still very good looking clean after 1000mi.