Fluids

[slash2244]

I'm in the process of resorting a '79 320i and i'm completely at a loss on types of fluid and amount. So far i know DOT4 for brakes and that's it. if anyone knows what/ amount for the engine oil, transmission, diff, and coolant help would be greatly appreciated. And any recommendations on spark plug material?

[MIKYZZ4]

https://sites.google.com/site/e21323i/e21-manuals

[tlapham]

Check out the FAQ's for more info, but in a nutshell, use 15W-40 for engine oil, most people run Redline MTL in tranny and diff. AR52 spark plugs work the best for stock ignitions, otherwise use basic copper core. Don't use platinum spark plugs in these cars. For your 79, getting rid of your points for electronic ignition and 8.5mm twisted core wire is a good upgrade as well.

[slash2244]

ohhh okay thank you, ive been told 5w-30 fully synthetic before and didnt know if it was right or not.

[sbcrockett]

20w-50 like the manual suggests, usually Castrol GTX, Redline MTL in the tranny like tlapham suggests, conventional 80w-90 in the diff (I've found it to be quieter than synthetic), 50/50 coolant with Water Wetter if you're so inclined. I'm usually a Bosch copper WR9DC+ guy but just put some NGK BPR5ES in the M20 yesterday and liking them so far

I've heard it said only synthetic for the engine if it's a recent rebuild...but I admit I'm not too knowledgeable about the subject

[slash2244]

sorry the manual is long gone to that car lol, but im confused is it 5w-30 ,15w-40. or 20w-50

[MIKYZZ4]

Depends on your ambient temperature range, in your part of the country.
I have already posted manuals info, look them over!!
Again :E21 Euro(323i, 320/6, 318, 316) Owners Manual - Care and Maintenance and Specifications Sections ONLY
Download Here
Oil info found on page#3 of PDF, which translates to page#91 on manual.

[320iAman]

https://www.bimmerforums.com/forum/s...se-in-your-320

Right now 15W-50 full synthetic Napa, I like the extra protection of Higher Weight oil, very true temperature has big impact on what weight oil to use. Next oil 15W-50 Mobil One as it has a higher ZDDP content which provides better protection for flat tappet Cams and so forth from wear.

Randy