Mobil 1 15W40 or 15W50.

Does your engine make noise? Valve adjustment quiets the valve train even though the rubber "hushers" under the tappet buckets may be really hard and flat or wholly dissolved by now.

Does your friend mean Shell 15W-40 mineral (dino) oil or the Shell Rotella Synthetic at a 15W40?

Prior to that, I always used Castrol 20W50 in all engines save for cold weather extreme temps.

DOOOOOOOOOOOOOOD

(I'm on a doood kick. Sorry.)

cheers,

dud.
--
Hyrdrocabons? Well, "drill baby drill." Conversely, I state, "Trees? Plant more, baby, plant many more globally."

As the others have stated.. Don't change a thing.
Bought my '89 new and have been using Castrol GTX 10-40 all this time.
300+K miles on it now.
--
'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.lyse.net/brox/TonyPage4.html http://cleanflametrap.com/tony/

...are both excellent "dino" oils that perform nearly as well as the best synthetics. They are designed for use in heavy duty trucks and other diesel powered machinery, but can be used in gas powered passenger cars with no ill effects and actually exceed auto manufacturer's specifications for oil.

If you have had good luck with Castrol, I'd keep using it. As long as you change the oil and filter regularly, I don't think that the brand makes much difference.

Greg

I'd stick with what has worked for you in the past - Castrol. I pretty much used Castrol GTX 10-40 in my 240 and it made it to 300k still running well. Used Castrol in my other cars too and never had a problem.

You could also consider switching to synthetic. Trouble is that with a high mileage engine it will leak initially until the synthetic has the time to do its thing cleaning the seals. Once the seals are clean any leaks should stop.

An engine cleaning with AutoRX is also a possibilty.

--
95 855 GLT Sportwagon 220k, 90 244 DL 300k+ - after 11 years has a new home