Originally Posted By: mechtech2
Those old oil viscosity/temp charts are a riot.
And they are apparently copied and still used here and there.
A 40 only good to 60 deg F? Yeah... OK.
For the SG quality oils of the day, im sure that was fairly accurate. Same with the 20W-50 recommendation for HOT climates.
Nowadays, im sure 5W-50 iff not M1 15W-50 would be good for the ETA, Super ETA, and actual 2.5L (M50B25, ETA was M50B27 engine.) Or, GC.
The BMW message board echoed the "seal leak" concerns and ONE user uses 10W-40 over on there (RedBaron6325 si his name on unofficialbmw.com, he puts 10W-40 in it) while the others all love 20W-50. Im sure 5W-50 would tide them over, if they dare to try.
The anti-30 stigma is alive and well on these cars, and it comes up a LOT with Audi, BMW, and M-B. Most of the time its accurate, too. (no tick, no leak on 40 and better oils in these cars.)
Quote:
One said the seals would leak, the other two said synthetic oil isn't recommended for that year. I argued that the M1 site says the only oil they make for my car is 0W-40 with no other options....they told me do what I want but no synthetic is their final word.
This all started when a buddy of mine (also owns an old BMW) got into the typical synthetic vs dino argument, he said I'd ruin my car if I put synthetic in after using dino. Of coarse I lost the argument (in his mind) after we called the dealers....
I've owned this car for 5 years, the guy I bought it from was using 10W-40 but didn't know what brand because a shop did his OC. I use M1 0W-40 and will continue doing so, maybe I'll try Rotella T6.. ?
May i ask why you arent happy with the M1 0W-40 you have in there now? its a hard oil to beat.
Dare i say it.. Try RP (Royal Purple) of the same grade.. 0W-40?
That, or GC. Or M1 15W-50.
FWIW, i put Dino 10W-40 in mine, too, but my dino 10W-40 was technically a blend. Then, in the summer, i went thicker. Mind you, my engine ran with its temperature up VERY high, 7/8 the temp gauge as a matter of fact. Never did figure out why, but it ran for three months like that before it finally made the extra tick up and overheated. I didnt have video back then, but it always got 20W-50 in blazing hot summer, always did well, had minimal consumption with 20W-50 had more with 10W-40, and ran until that happened, and even after. Incredible car and engine.
I also put top-up quarts of OLD Pennzoil 5W-50 and also Syntec 5W-50 in there with no real improvement, so i stuck with 20W-50. If i had it to do over, i would try GC, and if that proved too light, id look at a 5W-50 again, perhaps MAYBE a thick 40, for that engine, though 5W-50 may edge out. That engine likes that grade, its echoed on forums for the car. (Old engine design, inclined to use thicker oil. They certainly did NNOT put 30-weight in them in Germany, when they were Autobahned, with SG-spec oil. NO!)
The BMW dealers were afraid of the new oil in the old car, and that you qould bring it back to them saying "You told us Synth would be OK and then it leaked." Strictly covering their butt. I dont blame them. What the oil will and wont do? You dont know until you put it in.
EVERY ENGINE IS DIFFERENT WITH THIS!!! Most do fine, some dont.
