gnx7

iTrader: (28)

I went to my local GM dealer and bought 4 quarts of GM Synchromesh fluid for a manual transmission. I have heard this helps with making shifts much much smoother. I have a freshly rebuilt transmission with zero miles and want to make sure this is the right stuff (steel shift forks, carbon blockers, D&D Master rebuild kit). At $40 for the 4 quarts I certainly hope so .

They also had GM Synchromesh fluid with friction modifier for the 1500 series (which I assume is the truck) and it said for automatic.

I assume I am right with buying the first fluid mentioned? I know the T56 calls for ATF fluid so I'm a little confused.

-Mark

calhoon

iTrader: (6)

With the carbon blocker rings( over std. paper) you should be ok. You will have a slower warm-up in the winter months and must accept the harder shifts that come with a higherviscosity oil. The 1500 is an light truck trans used in S10 an lighet C/Ks.It is not a good idea to ever add a friction modifier to any Tremec trans.

gnx7

iTrader: (28)

Thanks bro. Winter in CA doesn't get as cold as OH thank God.

Anyone else care to verify if this is the correct fluid?

What fluid are you guys running?

-Mark

AtlantaRTA

That brought up an interesting point. My T56 was rebuilt recently and the local GM dealer in Lawrenceville told my rebuider to use the friction modifier with the auto trans fluid. I recently pulled the trans out to change clutches drained and refilled with regular valvoline dextron 3 fluid without the friction modifier. It seems so far that my third gear is not as notchy as with the friction modifier. I thought the friction modifier was used to cause rear end differential clutches to slip and not give as much chatter. That seems to be the opposite of what you would want in a transmission synchro. You want them to grip each other. Does this make sense? Why would you want to add friction modifier to a T56?

calhoon

iTrader: (6)

My point exactly don't use it in a T56. It seems there are those that do add modifiers. There are some synchronizer system/ materials that can handle & benefit from it .