Pennzoil Synchromesh not the same as GM version

[perryg114]

Well I took folks advice on here and put in the much cheaper Pennzoil Synchromesh and it is just plain old gear oil. I ran the GM Synchromesh in my Eclipse because it shifted like [censored] with the OEM lube. The dealer gave me some GM synchromesh and it shifted like butter. After over 100,000 miles on the GM lube it looked good. I replaced it with the Pennzoil variety and it shifted like [censored] again especially while cold. The GM stuff was good no matter what the temp. In the winter the trans never warms up enough to shift well with the Pennzoil. In the hottest months it does ok but still shifts like [censored] when cold.

Perry

 

[mstrjon32]

Sounds like...you should change back to the GM stuff?

I'm going to fill the Aisin AX-15 in my Jeep with some Redline MT-90 soon. It better be like butter, for almost $10 a quart.

 

[MolaKule]

Quote:
plain old gear oil.


I beg to differ. The Pennzoil Synchromesh is a 9.5 cSt GL-4 lube designed for synchromesh transmissions that use this viscosity. It is more than just plain ole gear lube. It is a blend similar to the older GM Synchromesh.


Could it be your tranny has a viscosity requirement that is different than the Pennzoil fluid?

Quote:
I ran the GM Synchromesh in my Eclipse because it shifted like [censored] with the OEM lube. The dealer gave me some GM synchromesh and it shifted like butter


Huh? Which is it?

 

[mechtech2]

There were 2 [maybe 3] versions of the GM synchromesh.
The Pennzoil Synchromesh was very similar to one of them, if not identical. It is a dino oil.

 

[unDummy]

Texaco and Pennzoil synchromesh and one premixed with the friction modifier. Too many PN's to keep track of.

Unless you bought some unsealed bottles(refilled by slick employees or returned by weasel customers), Pennzoil would be identical to the GM fluid for shift quality. A UOA/VOA would've been interesting. What GM PN did you use?

100k on a gear oil is abuse in itself. The Pennzoil had some cleaning to do. Looking good means nothing to a fluid. UOA!

What does your tranny require?

 

[EricF]

Pennzoil is the SOLE supplier of Synchromesh fluid. They have the rights and patents to it, nobody else makes it but Pennzoil because of this. There should be absolutly no difference between any brand.
I got this info from the pennzoil website a few years ago while I was trying to find a Redline substitute, which I didn't officially, but found something that would "work". (MT-90)

 

[unDummy]

Texaco makes Synchromesh too.

MTL is the synchromesh substitute. MT90 is a 75w90 weight.

 

[ArrestMeRedZ]

I don't mean to offend, but are you positive you were given GM Syncromesh, and not GM Synthetic Manual Transmission Fluid, PN 12346190? When I researched this fluid (it was required for my truck, and I wanted to avoid buying from a dealer parts department), it was made only by Castrol (also called SYNTORQ LT), and according to an answer I got corresponding with Castrol, was only available from GM and Chrysler.

Since then, I've found that AMSOIL makes a fluid that meets this spec, Synthetic Manual Transmission and Transaxle Gear Lube (MTG). It's a 75W-90 GL-4 oil, and has been recommended for a number of other transmission/transaxles, including the Eclipse. Haven't tried it yet, but it's going in the truck as soon as I'm out of the GM stuff.

 

[Tremo]

Careful guys, if you're looking to change the oil in a Borg Warner T5, the later versions (so-called "world class") call for ATF. Those trannies are made today by Tremec, and all their stuff uses ATF.

I always thought that ATF in a manual box was a little wierd, I'm running RP Synchromax in mine, works fine.

 

[Buffman]

my 91 ranger with the Mazada 5 spd (M50D I think) called for ATF. It had 240K on it. It shifted fairly roughly till I went with a mix of M1 ATF and P Syncromesh