Got a question for you guys, my dad and I could use some help before we cause a bigger headache. We are looking for some advice on seal and gasket replacements/ tips. I can take pics and add them as well to help. The C4 is out of the truck. We were working together replacing seals and gaskets yesterday and all went good until I started researching this morning. We were working on the passenger side “servo cover” gasket, we unbolted the 4 bolts and took cover off. My dad pressed the piston in while I scraped the old gasket off very slowly. We put the new gasket on and bolted it back together. We were done, thought we were good but I was reading that obviously we did this wrong and that there is a possibility something (a band?) could have fallen inside the transmission. We obviously weren’t looking to open up the tranny any further... can you gurus please help point us in the right direction of what to do/look for/ what will happen if we do nothing and take a chance. We obviously aren’t gonna do nothing but we do need help. Any other tips with the other seals would be helpful as well. I ordered a gasket/seal set. So far we have done dipstick tube o ring, pan gasket, and that pass side servo gasket. By the way, in the process of getting a manual but I’ve always preferred the forums. TIA

 

The C4 is a leaky little transmission for sure, to answer your question it is possible that when you removed the servo that the band strut could have fallen off. The end of the servo indexes a piece of metal that connects to the intermediate band (2nd gear), most of the time there wont be a problem removing to the servo and not dropping the band strut but if the transmission was being rolled around or subjected to harsh movement its possible to have the band strut to fall off the band. The only way to know for sure is to look at it or adjust the band, the band adjustment should tighten down at 1.5 to 2.5 turns in then, if it turns more than that there is a good chance the band is not indexed on the servo. If it tightens down back it off a turn and a half and then tighten the lock nut down.

The C4 suffers from a leaky shifter seals too, there is two seals in the linkage, a small o ring and seal in the case, this would require the removal of the pan and valve body to get to the internal linkage nut to get the linkage out to replace this seal, I would replace this seal now because its even harder when the transmission is in the vehicle. This is a tricky set up to get out and back together properly so take you time and with the valve body removed to will be able to see all the band struts for both bands to insure they are properly connected.