Have a 2005 S-Type 3.0 128K.. Never had serious engine trouble. I drive about 6500 miles a year and am a normal driver. Not interested in racing around in Dallas traffic. There are more fun ways to end up in the hospital.

The guy that use to own Jag Mag here told me that 15/20-50 weight oil was good for this engine as it helps with the VVT's.

The last time this car had 5-30 in it was at about 40k when the last Jag oil change was done free by the dealer. Since then I have used 10-40, always synthetic (now the one for high mileage cars since 70K).

Always a top of the line filter.


Any thoughts on the 15-50 oil in these engines?


A second question I have to have my valve cover gaskets and the related ones replaced (not that any jag owner here has ever had that done). As i understand- what Jag indicates that I should use new bolts all the way around in the job. What about the rubber gaskets on the bolts? True, false or mixed?

Thanks as always for the help.

Tom in Dallas/Plano
2005 S-Type 3.0 128K

 

No idea on the bolts. I have 140K on my 3.0 and still run the factory specified 5W-30; I also run full synthetic and drive a similar amount of miles per year. The car does not require any "top ups" to the oil between annual services.

Given the high summertime temperatures in Texas, a -40 weight may be okay, but unless your engine is severely worn, I would suggest the -50 weight is too viscous for your engine.

The Jaguar Forums member to ask is Glyn M Ruck. He is an oilco tribologist and hangs his hat over on the MK2, etc., forum.

 

Thanks. Although after more than 80 k on 10-40 and living in TX with the high temps, I have zero intention of going back to 5-30. I notice you are in Montana, so the temps are a touch different.My question is about the 15-50?

TBB

 

Summertime in eastern Montana graces us with many days of 100+ degree weather. I was not suggesting that you revert back to 5-30; however, I did mention that unless your engine is severely worn, 15/20-50 may be too thick for your modern engine. I also suggested that you contact an actual expert on these matters who is a Veteran Member of these forums...

 

Thank you.

TBB

 

Using 15/50 or 20/50 is definitely not a good idea. You are far more likely to build up sludge and chances are it is poorer quality than your engine was designed for. Stick to using the manufacturer’s recommended viscosity and quality. Avoid enhanced mineral oil, use fully synthetic.

 

OK thanks.

The manual says I can use 10w-40 and that is what I have been using and ALWAYS full synth.

TBB

 

In a hot climate that is probably about as thick as you should go. Well done for always using fully synthetic👍. On a fairly high performance engine it is essential to use good oil like that. Your engine will wear much slower using fully synth.