GL-4 Oil for Geo Tracker Transmission & TC

[Sedin26]

I'd like to change the gear oil in the 5-speed transmission and transfer case on a 4x4 1994 Geo Tracker. I think a GL-4 would be best but I am also looking for a dino oil if one is out there.

So far I only have the option of using the GM oil, which is about $20/quart, or I could go for the Redline or Amsoil. If nothing else can be found I'll go for one of these synthetics but it's not my first choice.


Is there anything else available that would be a bit cheaper? I see there may be a Pennzoil GL-4 75-90 that is a full synthetic but I haven't seen it anywhere.

I also wonder about the Pennzoil Synchromesh but it doesn't seem to match up to the needed GM part #

It looks like a dino GL-4 may be a thing of the past...

 

[expat]

I have used Pennzoil Synchromesh in place of GL4 in two of my vehicles. Both times the shift quality has improved considerably.

Yes, GL4 is hard to get hold of, but many older British cars require it.
You might inquire with the Victoria branch of the Old English Car Club. They may have made a club purchase.

 

[artificialist]

Don't change the oil until you know the viscosity your car needs. You could go to Amsoil's website and buy it from one of BITOG's Amsoil people

 

[Sedin26]

There is definitely some question as to what would be compatible - Synchromesh seems to be meant for later model years - and it is difficult to find any sort of GL-4 in my area that is a name brand fluid. The GM fluid is over $20 a quart.

I'd already decided to follow your good advice and just buy the Amsoil. I know it meets the specs I want and will be a good product. There's no sense in trying to save a few bucks then having to rebuild the transmission down the road.