I just got a 1985 gsl-se and it needs an oil change. I'm not sure what kind of oil to use so i was wondering if you guys could help me out.

 

Amsoil synthetic is great, a bit expensive as the engine injects a small quantity to lube the apex seals, but if you can afford it, you will not be disappointed. It runs about $4.50 a quart. -Mike

 

Castrol GTX all the way!

 

Castrol GTX... No doubt.


Here is a good comparision...

http://www.vtr.org/maintain/oil-overview.html

PS-synthetic is supposedly bad.. doesn't burn, just turns to plastic goo...

 

So that says 10W-40 is bad does that mean I'm screwed because that's what I have in there now....

 

Synthetic ?!?

Did I just read someone using synthetic oil? I'm not sure here but doesn't that promote carbon build up?

I personally use Moble 1 non-synthetic. Haven't had any problems and great results. Costs a little more.

-Error402

 

royal purple !!!!

 

10-40 may not be bad... just less than idea.

but then again, that site isn't for our cars. I just thought I'd share it as a good place to bookmark lots of useful info about oil...

 

I use Castrol GTX 20w50 with some MMO in there too. You have a little more to worry about than your oil change though. Get that damn idle problem fixed

 

Havoline 10W30. This thread will have 50 choices when it's done. Most of the guys will go with GTX, however, the flashpoint on Havoline is higher - since heat is the rotories worst enemy, I wanted an oil that will hang on in the heat (IMO only). A lot of guys will also tell you Synthetic is bad news and just as many will tell you its OK - but the bottom line is......... Mazda doesn't recommend it!

 

Castrol GTX 20w50

 

I am a die hard Redline oil user. Burns clean and is awsome all around. Not cheap at all though, $8.00 a quart. But I feel it is completly worth it.

About the Synthetic debate, I think it comes up to personal choice. Neither side has hard evidence as to wether or not Synthetic is bad in the rotary.

 

Thanks for the suggestions guys. I think I will probably go with the Castrol GTX 20w50. What kind of oil filter?

 

What about cold climate areas. Like where I live? It can get to subzero temps around here in the winter...in the summer though it's pretty hot and humid.

 

Castrol GTX 10W30 is what most car manufacturers use. A Fram oil filter is fine for normal driving applications.

 

I wouldn't put a Fram on my lawn mower let alone my car. Cut one open and compare it to just about any other filter and you'll see that you are just paying for an advertising campaign, not improved quality. I use a Bosch myself, it filters a little better than most but is not as expensive as a Mobil-1 or K&N.

 

Purolator...10/50W Castrol

 

Castrol GTX 20w50 with a WIX filter!

 

I use Pennzoil 10w40; just the basic stuff. What's odd is that I buy it at Walmart cause its dirt cheap there in 5 qt. jugs.

 

Castrol GTX seems to be the prime choice.

 

I've used Valvoline Durablend 10w-40 semi-synthetic for 10 years on an engine that still ran strong up to 282,000 miles before swapping it out recently. I will continue to use it with only an original Mazda filter and change it every 2500 to 3000 miles. If it wasn't for cost I would use Royal Purple. Interesting article here though, I was right there but not paying attention http://www.mazdausa.com/mazdaspeed/t...otary_news.asp

 

If your using a non-synthetic, than Castrol Gtx 10-30 is the best, by far.
I also recomend the K&N oil filter. Has some of the best filtering for the money. Runs me somewere around $6.00USD for the filter.

 

It gets far colder on the Canadian prairies, and 20W50 starts just fine in sub-zero weather. In a piston engine you'd be screwed, but rotaries have low mechanical resistance to cranking and heat up faster than a fat man on a summer day

 

Thanks for the info. lol

 

GTX 25w-50 always. In my 375hp 10th anv. TII in my new to me 83 GSL in my jeep ect.