i know this has been asked b4, but i searched and couldn't find a list of different oils that are good for the 7. i got a brand new eninge in mine, and my buddy got the oil for it. i forgot what kind it was, i know it was from valvoline at least im pretty sure. like i said, i have a brand new engine so im looking for the best oil for my car. any help would be great--thanx

 

Castrol GTX 20W50

 

 

If your in a cold climate,10W30 is fine in the winter.I run it in my TII engine during the winter months with no issues,helps a lot with cold start oil pressure.20W50 is tar in the mornings.
Just stay away from 10W40 anything and dont run anything crappy quality.

Castrol,Valvoline,Mobil,Chevron are all good dino oils.

 

agree: Castrol GTX
The _real_ secret is change it and the filter every 3K miles....
Stu Aull
80GS
Alaska

 

why stay away from 10w-40?

 

Too large of a viscosity range for a dino oil to cover without a lot of additives.Additives which do nothing to help with lubrication.
Theres many ongoing debates about it,but I do know for a fact that there are car/bike makers who specifically prohibit 10W40 use, if you want to retain your engine warrantee.

 

i say 20W50 Castrol GTX with the red cap. at least the ones here have it

 

Have 10w 50 hpr 30 penrite and love the smel of it!

 

like steve said 10w30 in cold weather seasons and 20w50 in summer time.

 

flame me if you will, but I always have, and always will run redline 10w 30.

 

I run Redline in all my other vehicles/bikes and in the RX-7's drivetrain,great stuff.
Im still waiting on a little more input about syn. in the rotary engine.
Im probably gonna try Royal Purple or Idemitsu on my next oil change and see if I get any inprovements in turbo spool,throttle response or oil temps.If I dont see any change,Ill just stick to dino juice.Its cheap, and I change it out every 2000 miles.....

 

So what qualifies as cold in regard to the FB (SE in my case) discussion? If I live in an area where it rarely drops below 40F would that be fine for 20w50 year round?

 

Ehhh,its cold enough for 10W30 here in the winter.
Im only 50 miles from you,its usually pretty cold in the morning and we dont get above 60*/ 70* in the winter.If your not racing or driving around in 90* heat,then 10W30 is fine.

 

Regular Castrol GTX is the only thing i trust for my car. none of that high mileage or synthetic **** either

 

Penrite HPR40 all the way!

 

I'm using Valvoline 10W-30 year 'round. Valvoline because when I investigated this a couple years ago here on the BBS, one of the members, who also was an API engineer, said he used Valvoline because it had lower ash than the others. So I picked Valvoline: why not? And I use 10W-30 because temps are pretty mild here and I have no problem with it.

I'm against using heavyweight oils like 40 or 50 weight, because they probably don't help lube and they may hurt. An oil that's too heavy can tear and cavitate in tight clearances and leave bearing surfaces exposed. Many ordinary car drivers think higher oil pressure is better and they can get it with heavier oil, but it aint necessarily so. Higher oil pressure, per se, does not mean better lube. When I worked on racing boingers we'd open up crank bearing clearances and journal clearances to allow more oil to pass, thinking that would reduce contact patch temps and refresh lube faster, and, I think, to provide greater margin in the differential temp induced clearance variations: by starting with larger clearances a given change in bearing clearance would be less significant. I guess it worked because with racing engines running at constant high temps and stress for long periods we lost fewer engines. But then, that's not how we operate the usual FB; at least I don't. When I go out in the cool morning and start my DD 7 to warm it up I like the idea that slippery 30 weight is running thru it at this critical time when some surfaces may be relatively dry and denuded of oil.

I add 8-10 oz. of Idemitsu premix (or regular 2-cycle in a pinch, or even MMO) to every fillup and haven't bothered to disconnect the OMP. I figure the rotor has the same lube problems as a 2-cycle. I change engine oil about twice a year, but I replace the oil filter more often. Oil doesn't wear out, it just gets dirty (you can actually filter old oil thru diatomaceous earth and re-use it: it comes out clean and clear and minus the additives).

My 4 rotaries have 70k, 120k, 140k and 150k and none have been overhauled or had a problem with apex seals. I don't expect any of them to break an apex seal, and expect that eventually one may be worn down to the nubbin, but not break.

 

So, doing that attempting to answer my own question thing, I read over the little owners manual and it says 10W-30 for -10 to 80F. 10W-40 for -10 to over 120F. And 20W-50 for 20 to over 120F. If I were going to believe that, it is not uncommon to go over 80F here so 10W-30 would come up a little short for that, and it almost never goes below 20F so 20W-50 should cover year round. I'm just quoting the 1985 owner's manual here, not stating an opinion of my own.