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The attached pdf has the oil recommendations depending on average weather temperatures
If it's only a short term stay then you might be ok. Maybe pick up a bottle of Lucas Oil Stabilizer just in case you get rattles while you're down there. It definitely resolved the issue on my N/A 4.0 in central California.
I suspect that 5w 30 oil may well show rattle signs in the heat down there.
These are the suggested viscosities/temps for normally aspirated engines,
Hope this helps.
Excellent. I may go with 5w-40w full synthetic to avoid excessive wear until the winter oil change. Is this a good idea?
I've been using Castrol Syntec 0w40 all year round for a looong time. Mobil1 0w40 would likely work just as well. Both full synthetics. Both easily found. Both inexpensive.
I'll look into 0w40 ready for the next change. I have been going with official Jaguar recommendations, but am keen learn of any other potential options, particularly with the normally aspirated AJ16 4.0.
If would be good to hear from others on their experiences with both Castrol Syntec 0w40, Mobil 1 0w40 & Porsche A40.
w40 oils seem to end at a max outside temp of 40C or 104F. Good enough for me.
5w seem to have a low end temp at -40C or -22F. 0w oils go beyond that! Good enough for me.
I have no idea why anyone would not want the lowest possible number to the left of the 'w' for cold starts. The right side number for this engine seems to want to be a 40 or 50.
w40 oils seem to end at a max outside temp of 40C or 104F. Good enough for me.
5w seems to have a low-end temp at -40C or -22F. 0w oils go beyond that! Good enough for me.
I have no idea why anyone would not want the lowest possible number to the left of the 'w' for cold starts. The right side number for this engine seems to want to be a 40 or 50.
I like this notion. The 0 viscosity on the low end will permit the engine to be immediately lubricated at startup, finding its way quickly throughout the engine and minimizing the buildup of deposits (as Mobil so clearly states on the vessel). During the heat of the day in Central California as I head south, the 40w viscosity will protect my engine against excessive wear. Since this is a "European Car Formula" I believe that the fully synthetic Mobil 1 should protect the 243.5 cubic-inch (4.0 Liter) 6-cylinder engine as I drive my way back through the San Joaquin Valley heading back to the Pacific Northwest.
So it seems the best option would be to go for an oil that works in all temperatures while retaining a consistent viscosity.
Is there any reason why you wouldn't just go for a 0w50? If not, why isn't all oil 0w50 or 0w40?
C to f is double and add 30 (I think)
Last edited by Nobeel Masri; 05-05-2021 at 12:25 AM.
My wife’s Honda Pilot likes a w20 oil. It all depends on the design and engineering, right?
The question is, why isn’t all engine oil 0wXX, right?
I don’t know.
They do make a 0w50, but it’s expensive.
It's been a long, long time since I last studied-up on engine oils.
However, years ago, there was difficulty in getting the wide range viscosity oils to reliably/accurately behave. The common grades (let's say10/30, for example ) oil had been perfected to actually behave like both 10 and 30, as needed.
The wide range types (let's say 0/40 or 10/60)....not so much. They we not 'stable' at the extremes.
I think at this point, you can head over to the Bob Is The Oil Guy (bitog) website if you want to continue to go down that deep, deep, deep rabbit hole.
So 10w 40 seems to be ideal for my location, tried 5w 30 once and the engine rattled a lot. Most likely the chain tensioner not holding the thinner oil.
If I switched from a 10w 40 to a 0w 40, should I expect to get the chain rattle back?
Sorry if this seems like a basic question, but I'm interested in anything that could better maintain the engine and keep it quiet.
by the time you go 20 feet down the road it’s already a 40 grade
Maybe some old mineral oil but most 10w-60 oils for sale now are fully synthetic "racing" oils which are going to hold their viscosity much longer than 20 feet.
Maybe some old mineral oil but most 10w-60 oils for sale now are fully synthetic "racing" oils which are going to hold their viscosity much longer than 20 feet.
I think the point being made is not that the oil isnt performing as advertised, it is just that within 20 feet, the operating temperature has already reached the point where the "60" part is no longer necessary.
As has been mentioned already, this is a very very deep rabbit hole, and at the end of the day all that seems to matter is that we are all driving with as much peace of mind as we feel we need.
For my own part, in the absence of any tangible evidence that these engines are going to wear out before I do, I am keeping it simple with oil and filter changes as recommended by Jaguar, with quality oils and filters of the specification recommended by Jaguar. She runs beautifully after some 170000 miles, and inside the engine seems as clean as a whistle. Adapting to a different and inevitably more expensive regime in the hope that it might extend the remaining engine life from a likely very large number of miles to, perhaps, an even larger number of miles isnt striking me as a priority at this point.
As ever though , with the great oil debate, each to their own!
Pretty much every Jag garage(or dealers) in UK I can think off will always use 10w40 in every AJ6 or AJ16, I will occasionally use 15w40, depending which one is cheaper when I'm changing it. If engine is a bit more tired and/or you don't live in climates with temperatures below -10C 20w50 will be the recommended oil here in UK. Oil type itself, if you change the oil regularly it really doesn't matter much what it is, except maybe to make you feel a bit better when spending a bit more on a higher priced oil
Oil type itself, if you change the oil regularly it really doesn't matter much what it is, except maybe to make you feel a bit better when spending a bit more on a higher priced oil
Which is the philosophy I adopted a long time ago. Buy what makes you feel good. The engine itself doesn't really care.
For my own part, in the absence of any tangible evidence that these engines are going to wear out before I do, I am keeping it simple with oil and filter changes as recommended by Jaguar, with quality oils and filters of the specification recommended by Jaguar. She runs beautifully after some 170000 miles, and inside the engine seems as clean as a whistle. Adapting to a different and inevitably more expensive regime in the hope that it might extend the remaining engine life from a likely very large number of miles to, perhaps, an even larger number of miles isnt striking me as a priority at this point.
When I had my X300/XJR I was driving 15k-20k miles/year. I changed the oil every 5k miles and used what whatever brand of oil was on sale that day. When I sold the car at 171k miles the engine was still healthy as a horse. These engines don't require anything exotic. It's purely optional.
Now, if I was striving for some sort of durability record (like getting 300k miles out of an AJ16 engine) I might be more particular. But at this stage of their lives I doubt that many of these old Jags are driven in such as way that the owner will see a real-world benefit to high-end oil.
I agree, 4 years experience of 2 XJ6's and many changes, 10w 40 is the ideal oil in my location. Until I see enough evidence to go to another option, I'll stay with it..
Going back to the question about driving from a cooler area into a higher temperature area, it seems the regular oil will work fine, although if chain rattle noises appear these are your options.
1, Add an oil 'thickener' like Lucas Oil Stabilser, this will keep the chain tensioner happy, I cant see why you couldn't keep the oil as it is until the next regular change.
2, Preemptively change the oil to specified viscosities before and again after the trip to ensure you keep the correct type. This seems like more hassle than it's worth, but maybe safer.
3, Just leave the oil as it is and accept the noises if they appear.
It seems that the engines are tough enough to cope with differing environments, but if its a longer environmental change then pick the right oils
05-03-2021, 12:31 PM
