Interesting, we all agree to disagree! Some people suggest 10W40 , some 5W30 some...
Now ,I'm confused! All I want is for my car run to properly
Honestly, I'm nervous because I have read that 5w30 is way too thin for that engine, but some of you disagree ,so...
Any final word ?

 

And your tensioners don't make noise?

I swear with 10w30 my engine was noisier than it is with 10w40. I know that it is an approved oil for the AJ16 engine but I am reluctant to try it....... I have a friend that switched from 10w40 M1 HM in his 80's MB 500 conv and he switched to M1 0w40 and he say his engine is way quieter. Not sure how that translates to the AJ16 engine though.


OP: I would just focus on the experience of the post from AJ6/AJ16 owners. The rest of the guys have V12's

 

Terry,


In your location and climate, play it safe and use a 40 weight oil. 0W40, 5W40 and 10W40 will all work fine in your application. If you only drive 1K miles per year, I would not over think this and choose any one of the above. There really is not a BEST choice, just pick one and go with it... Enjoy your car.

 

I'd ditch using the light blue text, it's hard to read.

Asking 'which oil is the best' is similar to asking 'which beer is the best'.

Here's my method:

Open the owner's manual. See what Jaguar recommends.
Use that.

Smile and nod when others seem to pretend they know better than the OEM. Especially when they start getting excited.

 

I think the wise thing to do ,is to go with 10w40.
Thank you all for your replies!
Terry.

 

http://www.jagrepair.com/images/TSB/XJS/12-58.pdf


I'd definitely keep the car with nothing lighter than a Xw40 oil. I used to run 15w50 in the summer and 0w40 in the winter. I just stuck with 0w40 for simplicity sake. Out where you live, the car won't see much cold weather I imagine. Xw40 or Xw50 is what you want.

 

Steve.

I've got Castrol conventional 20w50 in my 92 V12 XJS. What advantage is there in upping it to the 20w60? Like most V12 owners I'm concerned about oil pressure when the engine warms up. I've read the various recommendations and I'm just not sure. I do less than 1000 miles per year.

Stephen

 

The first number (20 in the above case) is the important number at cold start. Under these circumstances the thinner the oil (that is the LOWER the number) the better for oil flow through the bearings of the engine.
Therefore, in your situation with your concerns, you need an oil such as 5w40 or 5W30. 20W cold oil will be far harder on your engine at cold start that 5W oil.
The pressure reading on the gauge is only a proxy for how well the oil is actually lubricating the bearings. ANY bearing would be perfectly well lubricated by a gravity feed, or by an oil bath, as long as the feed was uninterrupted. The actual lubrication effect is at the molecular level and is caused by the interaction between the bearing itself and the oil film. The rotation of the bearing actually winds the oil film through the bearing surface, just as a mangle winds wet clothing through the rollers.
Thicker cold oil makes this action more difficult, while thinner cold oil helps it enormously. Remember, oil pressure is to ensure there is oil AT the bearing, NOT to squirt oil THROUGH it. A V12 at cold will have quite enough pressure at 15 or 20 psi to do what is required.
Greg