Yet another question for anyone out there...

I just need a quick clarifiaction...
I have a 1984 GSL and the shop manual tells me to use synthetic oil, but everyone else tells me that I shoudln't. Which is correct? and whats the reasoning behind it?

 

run a search under the 1st gen section on oil and you will find all the big debates

 

My 1985 Factory Shop manual tells me nothing of the sort. Neither do the 1st gen or 2nd gen Haynes manuals. They do, however tell what grade and type of oil to use.

Mazda has NEVER reccomended the use of synthetic in their rotaries.

 

Synthetic in rotary = bad news
go with pennzoil or castrol gtx

 

Never use Pennzoil or Quaker State - they are not good for the life of the oil control O-rings.

 

Hey guys and gals I posted the same question to Racing Beat, who we know is well informed on rotarys. Their response was after break in their research has shown Royal Purple to show favorable results, as well as a horsepower increase.

 

They used to say the same thing about Redline, and AMSoil before that. It all depends on who is giving them the better deal.