TCI Competition series TH350 Problems!

[ss3011]

Does the trans actually shift, from 2nd to third, or do the wheels just turn at the same speed. Even in third gear, intermediate clutch is applied. The 2nd gear roller clutch or sprag just overruns. If the trans locks up in 1st gear, then you have the forward clutch, low/reverse clutch, and either the intermediate clutch or the high gear clutch on. Suspect cross leak or a missing check ball. Most race trannies would not have the low/reverse clutch on in 1st gear. Street manual VB's put it on in 1st to give low gear braking. You should focus on figuring out how oil pressure is getting into the intermediate clutch or high gear clutch circuits, when you are in 1st gear. It is also possible your intermediate band is coming on, in low and holding the high gear drum, just like the intermediate clutch would be when in 2nd gear. Only thing is, it has low capacity and would probably start to slip if you got into the throttle, when "locked up" in 1st gear. When the transmission was rebuilt after being overheated, it is possible that some plastic parts, changed "shape" and were not caught or replaced during the rebuild. Those parts like an accumuator piston, or band servo, could be a source of a cross leak.

[dartman]

check the shifter cable,see if the adjustment is right.

btw did you have the low/rev sprage out,it can go in backwards.

[The Hawk]

I agree,check the shifter linkage. On a TH 350,if you pull the lever back into low gear,and then a little further back it will allow fluid through a different passage and act like a trans brake. Lane

[HotRodGMC68]

the sprg was not messed with and went in as it was when it came out. I checked the shifter cable adjustment and it was right on per Hurst instructions.

When we tested the pressures I crawled under the truck, removed the shift cable and shifted it by hand at the transmission, letting it settle in the detents. no change