Right/Best Oil for my Tremec 600 TREMEC ANSWER

[dpcd67]

   I just got a shock; I went to buy some oil for my Tremec 600 transmission; I thought I would get the GM synchromesh 12345349. The shock was that the GM dealer wanted $26 a quart for it, and it takes 3 quarts. (5.28 pints). The girl at the counter said that price must be for a gallon until she retrieved a container of it and we both saw it was a very small bottle of oil.
   The alternative oil they recommend is Dexron III/Mercon ATF, which I found for $4.99 per quart. My question is, do I need to spend $78, or $15; I will spend whatever I have to for the best results, but is there really any difference?
What do you use?

[daveh]

Get the GM Synchromesh it's a little costly but overall the best for those transmissions.  It doesn't take that much anyway. It only takes 2.7 quarts.  Not a lot for piece of mind and smoother shifting.  Good luck

[bigblue73]

Redline oil makes a synthetic as well as Penzoil.  I would try another GM dealer though.

[Racer57]

I was told not to use Redline. Something about its ingredients deteriorates surfaces faster in newer trannys. I really didn't understand, so I didn't argue. 

[Chryco Psycho]

Shop around I have used syncromesh before & I think it was $12 / qt or so , try rock auto maybe

[dpcd67]

The only two choices they give you are the GM, or the Dexron III stuff.  But if they give both choices, my assumption is that both must be equal.
Anyone else? What do you use in your Tremec?

Guess I will call Tremec; I read that that part number 12345349 has been replaced by 88900333. And Pennzoil makes a synchromesh oil with the 12345349 part number as well.

[Travis72]

Penzoil makes the Synchromesh for GM and also sells it themselves at less than 1/2 the price of GM.  I was able to find it at a local Autozone but you might have to check a couple of them to find it.  Otherwise you could always order online.  I would recommend the Penzoil.  That's what I run in my TKO.

http://www.pennzoil.com/other-car-products/transmission-fluids-and-gear-oil/manual-transmission-fluid/

If you can't find it locally, here's one price online:

http://www.amazon.com/Synchromesh-Manual-Transmission-Fluid-quart/dp/B0002KL098

Everything I've read for the TKO says to use the Synchromesh only.  I think the Dexron is for use in the T-56.

Travis
72 Cuda

[dpcd67]

Good; Penzoil 12345349 I can get. Thanks.
 On the "installation Tips" page that came with the Tremec, it says that either GM or Dexron III/Mercon can be used "for all TKO transmissions". Also on their web site. But I have read that the GM works better/shifts smoother. I will get the Pennz.

[dpcd67]

Went to Advance Auto and got 3 quarts of pennzoil; it even says on the bottle that is for all applications of the GM 12345359.

[dpcd67]

And here is the final word I got directly from TREMEC today; "Thank you for your interest in the Tremec Product Line.  We recommend Pennzoil Synchromesh fluid for your application."
Case closed; thanks to everyone for their help.