What transmission fluid for 4-speed manual on 84 Cavalier

[brianl703]

GM originally recommended motor oil for this transmission, which is an M19. As far as I can determine GM updated the fluid recommendation to Syncromesh fluid, per a post on a Fiero forum. (The Fiero used this transmission as well).

Did GM ever recommend ATF for this transmission? Someone wrote "Dexron" on the cover of the owner's manual.

 

[Zaedock]

If the original lubricant was motor oil, I would run either a synthetic 5W20/30 or use Pennzoil Synchromesh or Royal Purple Synchromax.

 

[BMW Dom]

MTL® 75W80 GL-4 Gear Oil

Popular for BMW (before 1993), Honda and Acura, Ford Focus, late-model Mini Cooper, Dodge & Jeep NV 1500, 3500, and 5600

www.redlineoil.com

 

[930.engineering]

.
If GM updated their recommendation to Syncromesh, why not use . . . . wait . . . . Synchromesh?
.

 

[nwjones18]

Another vote for just using syncromesh. Props on driving a 4spd 84 cavalier.

 

[brianl703]

.
If GM updated their recommendation to Syncromesh, why not use . . . . wait . . . . Synchromesh?
.

I wanted to confirm that they actually did, for all I know, the post on the Fiero forum is not correct.

None of the TSBs for this car available from Alldata mention it, and a Google search turns up very little.

 

[brianl703]

Another vote for just using syncromesh. Props on driving a 4spd 84 cavalier.

That's what I'll do. It's a station wagon, my dad bought it new. It had been parked in the garage at his house for 10 years. I had to put a new fuel pump in it. After it built up pressure it started right up. I don't know if the car was sitting because the fuel pump died, or if the fuel pump died from sitting that long. Dad is no longer around to ask.

 

[dlundblad]

.
If GM updated their recommendation to Syncromesh, why not use . . . . wait . . . . Synchromesh?
.

This is as bad as the “follow your manual” parrots.

The Volvo in my signature does not use the oil or PSF that is stated in the manual nor would I have known otherwise if not for asking about it here.

 

[nwjones18]

We had an early 80’s Oldsmobile Firenza wagon for a while when I was a kid (when’s the last time you heard of one of those?) hope your Cavalier is more reliable than I remember that car being.. haha

 

[930.engineering]

This is as bad as the “follow your manual” parrots.

The Volvo in my signature does not use the oil or PSF that is stated in the manual nor would I have known otherwise if not for asking about it here.

Bad? Did I say 'do a search'? Did I say 'don't ask'? If this gearbox does
work with engine oil it should work even better with synchromesh. At
least using synchromesh is rather reasonable.
.

 

[nascarnation]

Those were built with 5W30 engine oil and should run fine on the nice varieties we have today. It would probably run fine on 0W20 too.

 

[dlundblad]

Bad? Did I say 'do a search'? Did I say 'don't ask'? If this gearbox does
work with engine oil it should work even better with synchromesh. At
least using synchromesh is rather reasonable.
.

Perhaps not bad. How about annoying, unnecessary etc.

Anyways, you’re missing my point. He read about the update on a Fiero forum and saw no actual proof of it from GM otherwise.. Hence his question.

 

[MolaKule]

Brings back memories. I bought a Cavalier for my daughter about that same time frame and she later gave it to our son.

We used my 10 cSt MTF synchromesh in it which was equivalent to the GM/Delco Synchromesh at the time. In fact any 9.0 cSt to 12 cSt@100C MTF will function well.

Amsoil MTF, Pennzoil Synchromesh, Valvoline Synchromesh, GM/Delco Synchromesh, Redline MTL 75W80, or Redline MTL 75W85, should work well in this tranny.

If the transmission has high miles and somewhat loosy-goosy, one can use the Redline MTL 75W85