cwcruzer

Is anyone experiencing rough, or dirty feel of the synchros when shifting?

I tried the GM synchromech oil and it provided me a with softer and smoother shifts, but still at times the shifting is butter smooth and then at random hard to place into 1st, 2nd, or 3rd, or in 6th. Again the shifting feel is not consistent. I tried changing gears at different speeds, RPMs, and the speed in which I move the shifter or push in the clutch and still nothing. I took it to the dealer once and a bulletin recommended changing the oil, which they did. Afterwards the effort was less, but still not clean. I later tried the GM synchro, and although it was MUCH easier to shift it is still not consistent. Honestly, it bugs the hell out of me and it takes the fun out of the drive. The car only has 7Ks, any recommendations?





V/r

CWCRUZER

SouthernBoy

Here are a few things to consider. First, two definitions are in order for this discussion.

Travel = the total distance the clutch pedal travels from the stop pad on the firewall to complete release of the driver's foot.

Take up = the distance the clutch pedal travels from the point of initial engagement to that of full engagement.


The day I bought my '04 manual TL, I test drove one on the lot that the salesman could get to easily (he did not go with me on the test drive). Right away, it was obvious that the clutch pedal had a rather short travel and an even shorter take up. Couple this with two other factors. Initial engagement began very early in the take up (like about 1 1/2 inches off of the stop pad). And from the point of initial engagement to that where enough clamping pressure was exerted to move the car was indeed very short and "tight". This is the primary cause of people having problems with the manual TL when they first get it. The one I actually bought felt the same way.

Some people who drive manuals tend to "lazy foot" the clutch pedal from time to time. By this I mean, occasionally one might find themselves not completely depressing the clutch pedal to the floor between shifts. With a car such as the TL which has a point of initial engagement occurring very early in the take up, this will cause a small amount of engine torque to continue to be transmitted through the clutch to the transmission because there will still be a little friction between the pressure plate and flywheel, and the clutch disk. If this happens, the synchronizers will have to work harder to overcome this engine torque while trying to match shaft speeds for the next gear selection. This, in turn, will prematurely and quickly wear synchronizer material and result in reduced smoothness and difficulty in shifting.

If this is the source of the problem, the only real fix is a complete tear down and rebuild of the transmission to replace the synchronizers.