Motor oil? What seems to work well in a high mileage m20?

[george graves]

What motor oil for something with over 230K?

[eliasmavs99]

castrol 20w50. Thick stuff doesn't leak as bad and protects durring summer.

[lawilson325]

I use 15w40 year round in all my BMWs and my pickup. My E30 has almost 220,000 miles. I use either the Texaco "ERSA" or the Chevron "DELO" motor oils. Note that these are the exact same oil, since Chevron and Texaco are the same company. These motor oils are mfg. using the highest grade of base oils, and therefore are designed for commercial use, such as in over the road trucks with very long change intervals. Not the cheapest oils available; I think I pay around $1.75/quart at either a distributor or at Walmart. These oils can also be purchased in gallons, and there's probably a little savings when bought this way. Castrol is another excellent/high-quality motor oil, but I don't believe it's sold in the US in the 15w40 grade....at least I haven't found Castrol in 15w40.

[MR 325]

20w 50 for sure, the brand is up to you. I run Valvoline.

[EVOIIIM3]

It really doesn't matter all that much, as long as you CHANGE IT!!

If you are cheap, then just get regular oil and change every 3kmi.
If you got some $$, then get some Synth and change every 3-4kmi.

Oil weight is different between synth and Dyno. You can't use a 0-30 dyno, but 0-30 synth is fine. The thinner the oil, the more liquid it will be, thus, it can leak more, but it will also lube faster then thicker oil, and protect the engine better at start up.

I run 0-30 in my E34 and 15-50 in the M3 year round. Both are on Synth either Redline or Amsoil.

The other cool thing is some synth oils have a really good detergent in them, this will really help clean up the engine and can actually give you more HP by not having so much blow by.

Doing a engine flush 2x a year is not a bad idea.

[Beej '86 325es]

I run 10W 40 Castrol GTX. Anyone ever try the Castrol High Mileage oil? Just wondering if it's any good. I have 250,000 miles on mine, I THINK that qualifies as 'high mileage.'

[Saul325is]

Kendall 20w-50, somewhat pricey, but the stuff is the best! Go even ask Trent ;)

-Saul

[Jon325i]

Castrol GTX 20W50. Northern California climate and my car has 221K on the clock. No issues.

Jon