Firstly, apologies as I’m sure that this has been covered ad infinitum, although I can’t find the info I need via searching, hence this thread.
I’m about to give my 1989 3.6 manual an oil change as I don’t know when it was last done, having just purchased the car. It’s covered about 10k miles in the last 20 years and the last receipt for oil in the car’s service history was in 2002. To be honest, I think it probably has been done since then because there are other new parts on the car that I can’t find receipts for either and surely the previous owner wouldn’t have allowed it to lapse for 20 years?!
The handbook shows a temperature diagram and I’m happy that 10w40 covers the temperature ranges in the UK, however the specs are BLS.22.OL.07, CCMC G3 or A.P.I. SE/SF. The problem is that I can’t find references to those standards on modern oils.
Castrol products were recommended by Jaguar further back in the service history so I was looking at, for example, Castrol Magnatec, which conforms to these standards: API SL/CF •ACEA A3/B4 •VW 505.00 •MB-Approval 229.1
I tried looking up the API standards on API.org to see if SE/SF have been superseded and didn’t get anywhere so rather than continue with that line of enquiry, here I am asking!
Can anyone throw any light on what modern standards I should be considering?
Modern oils will do just fine Simon, and I use out of the shelf oils on my 86 V12…
Oil technology has advanced quite a lot since 1989 and therefore the oil specifications have changed, and every new spec is supposed to be backwards compatible.
The only problem would be that zinc content is less and less and if you are really concerned about that there are some oils with higher zinc content, plenty of info in the archives.
I used 10W40 instead of 20W50 and lost 10 psi at 3.500 rpm even though I am within the temperature range of the W40.
I aim to switch back to 20W50 to see if I retrieve 10 psi. Because, as the saying in Germany goes: “The devil is a squirrel” and I may have another problem aside from the oil.
I cannot comment on zinc levels which had been discussed endlessly (until you get nauseous) for pushrod V8s with much higher spring pressure.
Thanks the the replies @Aristides et al - I’ve nipped out today and picked up some Petronas 10w40 today along with a new filter and other service items for the car. I’d read a bit about the problems associated with low zinc content and I’m going to get some of this additive to be on the safe side:
I think at 31k miles the engine is just about run in (!) but I want to look after it.
Picking up the oil and other bits was my first proper drive in the new car today and was thoroughly enjoyable - I took the long way and ended up doing about 20 miles just to see how it drove.
I did unearth a bit of an issue that I was kind of expecting after consulting the service history - a new thread about that will be forthcoming fairly quickly
Anyway, that’s a little job for the weekend: new oil, filter, plugs, air filter and antifreeze, It’s booked in with my local friendly brake specialist next weekend to have the brakes overhauled, too.
Stick to pure 5w / 10w40, Castrol is enough, stay away from additives - there are no miracles between physics and metal. Frequent oil change is better than the best marketing.
One thing to mention - I have seen low mileage AJ6 engines in worst condition than these with 160k. You’ve bought XJS stashed in UK or imported? Guessing it wasn’t packed in vacuum bag all the time, in the place surrounded with water… Where was it stored, how often was it started to prevent internal corrosion… Take out the rocker cover if you want full picture - cams will tell you full story, same as oxy on aluminium and zinc-coated components…
Hi @XjsBanger - Yeah, I’ve bought some 10w40 semi synthetic oil and I’ll bung in some of the ZDDP additive in case it makes any difference - it can’t hurt.
The car hasn’t actually ever been stored as such - the mileage has accrued fairly steadily over the years, but not by very much. If you check out its MoT history (reg number Bravo X-Ray India 4 4 4 0) you’ll see what I mean.
The car was parked in a garage near Cambridge for most of its life so it’s survived very well all things considered.
There’s a very slight weep at the rocker cover so in the fullness of time I’ll take it of and sling a new seal on it, but I’m sure it’ll be peachy under there.
There is not such thing like OEM seal, especially 30 years after finished series production.
Whatever you’ll get from ‘TheJag’ dealership is nothing else than branded replacement from one of the suppliers offering best cut for the guy in purchasing department. Consider this a first hand tip and don’t bother following ‘OEM’ in the future…
Any seal will do, replacing it is a no-brainer and it’s a great opportunity to inspect cams for corrosion artefacts…
Worth mention - Jaguar was aware of the problem with leaking and amended workshop manuals - to add silicone sealer under the half-moon rubber bits…
I will say more…for Janusz…there ARE differences is metal protection in oils…most significant for flat tappet cam engines is the zddp content…it is most important in high valve spring rate engines…but still important in flat tappets cam set ups. Oils used to have the zddp in the correct ppm, now many do not…as the cam/tappet is different, and catalytic converters become clogged quickly with zddp IF enough gets thru to exhaust…(another topic). Zddp for flat tappet should be in the 1000 to 1200 ppm range. Many oils have some…700-900, not enought. Too much is also detrimental…so adding an additive is not the best way…unless you can calculate ppm or follow mfg directions as to how much to add per quart of oil, but then you need to know how much zddp was in the oil you have in the first place…complicated. So best to just buy and use one of the many oils with 1,000 to 1200ppm…some called classic or hot rod. One can look up oil company websites and check…such as for the Petronas. For Mobil 1, they have a chart…some of their oils meet the 1000-1200ppm, and some do not. The 15-50 does. Most flat tappet cam engines did not have a catalytic converter…but some early oned did…before the zddp action in the cat converter was known. Anyway…TONS on the web and in archives. Some think snake oil and marketing…those are the well meaning folks who have not read enough…(you can, on the web, find at least 1-2 sources to prove the Moon really is cheese, and that aliens live in the center of the Earth).
Nick
I can confirm that aftermarket cam covers are too large for the AJ16 engine. I’ve tried enough of them, enough times. Believe me, I HATE spending the extra extra extra money on an OEM gasket, for something as simple as this, but if you have an AJ16 engine, it’s the only one I have come across that fits well.
I have no experience with the AJ6 engine. However, I ran an XJR/6 (AJ16 engine) for many years as a daily driver. I bought the car with 29k miles and, frankly, gave almost zero consideration as to the oil I used. “Whatever was on sale that day”. I changed the oil every 5k miles.
I sold the car at 171k miles and the engine was running as sweet as can be, no smoke, no noises, and oil consumption (1 quart/4000 miles) never changed over the life of the car.
Unless your plans include one of those “I drove this car 500,000 miles” contests, too much fuss over engine oil might not make much real world difference.
I wouldn’t even mention ZDDP here. Not sure where you’re based but I’ve heard that worn engine oil analysis in US is something common, unfortunarely not in Europe… Just mentioning as ZDDP goes away over time, that’s the real wear factor, not the actual content to start with - as per Doug’s comment above. Frequent oil change is the key.
You’re asking a regular guy to calculate the ZDDP content in the purchased oil and introduction of additive containing the same - into modern engine made of aluminium. This is not a Chevy BigBlock, on the overdose you can make more damage over 5k miles than actual 500k mileage will do… That’s why I’ve suggested Magnatec - at least Castrol still reports 800ppm in it on the datasheet. That’s why I’ve suggested semi-synthetic as full synth are having less to none ZDDP content.
Just saying…
read more Janusz. there are full synthetic engine oils with zddp in the 1,000 to 1200 ppm range. As I said, Mobil 1 15-50 is one such. In my comment I advised AGAINST adding a zddp additive yourself…as it is difficult to get the ppm right: the manufacturer instructions do not know what oil you are addint it to…(does the oil you used already have say 800ppm, or 400? or none). So one can buy a classic oil that has the zddp in the 1000 to 1200 range and that is that…got it…and no downside, as it is not too much, nor too little. It is quite simple. Yes, clean, frequent changes of engine oil and filter. Nick
I would love to try Mobil1 you’ve mentioned, however can’t find anything regarding ZDDP content on their datasheet…
Maybe I’m missing something - please advise if you’re able to find it. In this place - it is worth noting that if something is not on product datasheet - it is not being tested for conformity by anyone, anywhere. It may be marketing or absolute bullshit… That’s “The Law” by the way…
That’s why I’ve mentioned Magnatec:
I’m not saying it’s a bad oil - I’ve never tested it however… I wouldn’t follow Mobil1 marketing as it’s quite creepy… Not sure about now - however 10 years ago it was rated worts lube ever during the friction tests - regardless of grade. It was also proven that amount of key ingredients ‘varies’ between the designated distribution areas (welcome to EU, land where everyone is equal). Hence, Mobil1 manufactured for f.eg. Spanish market was nowhere close to the one being sold in Germany while the one in Hungary could be a fish oil.
Just hoping they’ve got much better now…
