Hello everyone here. I have a C4 tranny that I am having some oil leaks on.There are 2 leaks,one at the tail shaft where the driveline goes into the tranny and the other leak is where the shifter arms are. They are both leaking fluid. How difficult is it to replace this 2 seals ( I am guessing that its seals that are leaking). If I need special tools to remove and replace this parts,I will have to take it to the transmission shop to have it done. I like to do what I can when possible before I take it in to a shop. If any of you have done this 2 repairs before,please let me know how bad it is to do this 2 jobs. Thank you for your help and or suggestions.

 

The output shaft seal on the rear of the trans is easy to replace . Just remove the driveshaft , pry out the old seal , run a bead of RTV sealer around outer circumference and carefully tap it evenly in place .
The shift selector shaft seal , if I recall correctly will require the trans pan to be removed, then remove the retaining nut on the end of the shaft and pull it out. Pry out old seal and carefully tap new seal in place using a socket or something that will fit around the outer circumference and carefully drive it in then reassemble the toothed link inside the trans to the shaft and reinstall the cable /rod on the outside of the trans. You will need a decent size container to catch the fluid when you remove the pan. You might get a filter kit for the trans that comes with the new filter and gasket. Don't attempt to use the old gasket and no type sealer is used on the new gasket, just install it dry. Some gaskets will allow you to use a few of the pan bolts to hold the gasket in place on the pan.The holes are a little smaller to keep the bolts from falling out. Make sure you install the proper fluid for that trans. It might be type "F".

 

Thank you very much for your help.I really appreciate it very much. I think I'll give a shot..I will do it slow so that I do it right. It will be a learning experience for me. I like challenges and this will be one of them.

 

May be too late: Check the slip yoke on the front of the driveshaft while it is inserted into the tailhousing by pushing up and down on the U-joint yoke. If it is possible to wiggle it up and down, the bushing is worn out, and a new seal will fail quickly.