i did the search but never really learnd which one is good to use. i am about to get a 91 TII i hear that mobile1 15w50 is good. i live in Cali where its mostly sunny average temp. thanks guys

 

i live on guam and just recently...past 2 oil changes....been using castrol GTX 20w50. its sunny all year round here on GUAM, almost like hawaii but a bit warmer. i havent had any problems with it.

Fred

 

yeah, i run 20w50 but i really should change it for the colder weather.....10w30 is what will be coming at. Just whatever you do, dont go to 5-w-20 i know it's still oil....but its like water. Oil is Oil, Have fun

 

Mobil 1 15W50 is a synthetic, and although there have been some tests showing that the modern better quility synthetics run fine in a rotary, there is almost no benift.

Now both Royal Purple and Neo, have dyno tests showing about a 3HP increase with their synthetics, use of a synth is generally not cost effective in Turbos where you need to change the oil at least every 3k miles anyway.

Castrol 20W50 will be a better choice, for living in SoCal, unless you have money to burn, or that extra 3 HP is really worth $35+ oil changes.

 

Engine - 10W30
Trans - redline
Rear Diff - redline

 

ok. icemark. sense i live in rohnert park i'll take your word.

 

Good choice, but use synthetic in the transmission and differential where it actually does make a difference that you can feel, and you don't have to change it for another 30-60K miles. I prefer Red Line synthetic gear oil, but there are other good brands available.

BTW, I have used Castrol GTX 20w50 in warm Florida weather for nearly 15 years with good results in rotary engines.

 

I have used Castrol 10-30 and I live in southern Florida.


I have over 300,000 miles on original engine....

 

I say, this is a fresh topic. Finally someone starts a discussion about oil.

 

Looks like you got a lemon.

 

Yep, I have used Castrol 20W50 in all my FCs forever. It doesn't ever get under 30F in our area, and the 20W50 is stable and flows down to about 20F.

Nice to see another NorthBay person up here.

 

That's very good! Last year, the original engine in my 90 GXL lost a rear seal at about 211K miles. The engine failure was probably due to a defective thermo pellet in the e-shaft. I put a new engine in this past summer, and my GXL is on the road again.

Regarding oil, I've used Castrol GTX or on occassion Valvoline. I used 20W-50 in the old engine, except during the colder months where I'd use 10W-30. In the new engine I'm running 10W-30 year around.

Hot_Dog
90 RX7 GXL
02 RSX-S