C4 Help

[fair67]

Hello
I hope it is ok to post this here. I have a 65 Comet with the C4 289. I lost all forward gears. Anyway does anyone know if any other C4 will work I can get one from a 67 Mustang 289 without changing too much? Any help appreciated.
Luke

[Joe Travers]

Have you serviced the one you have? Is the shift linkage and front band in adjustment?

I would be hesitant to pick up another old transmission to 'fix' the one you have, unless it's out of a running vehicle and you know condition is good. Been there, done that a long time ago. The labor and cost will make you learn words you never knew existed.

Joe

[fair67]

Joe
I did service it twice and I adjusted the bands. After the first fluid and filter change it worked for a while and then started slipping I adjusted bands , it was better. I then serviced it again fluid was terrible it worked a bit then I lost all forward gears. Been parked since.
Luke

[Rootsy]

Rebuild It. It isn’t that expensive or difficult. Minimal tools required. Probably spend more time cleaning and inspecting components than actually disassembling or assembling.

Do you still have reverse?

This is a pretty good step by step video if you want to tackle it yourself.

https://youtu.be/MKIvPdYB490?si=bcu1gG8dEHtWOMK4

[fair67]

Rootsy
Thank you for the reply. It does still have reverse thats how I got it in the shed. Reverse seems to work great.

[Rootsy]

Rootsy
Thank you for the reply. It does still have reverse thats how I got it in the shed. Reverse seems to work great.

That rules out a pump or converter problem. Pretty good chance you have an internal leak preventing the forward clutch pack from engaging (no low = no other forward gears either). Could be a number of things but to root cause you really need to just tear it down.

Last one I had that did this was a 4R70W in my 1998 F150. In the case of that one the lipped seal on direct drum piston had hardened and a small chunk broke out. Instant go to no go… Had the same issue in the original C4 in my Cyclone a long long time ago. That one just lost forward momentum suddenly and then stopped moving forward. The sealing ring had cracked.

[fair67]

Rootsy
I wanna thank you for the advice at least it is good to hear that maybe the pump and convertor are ok. Also thanks for the video It is a very good one watched it all with the wife last night.

[Caveman49]

I agree with fair67, the video was very informative, I like the way he explained problem areas and things that people forget to do, or overlook.

[Rootsy]

I agree with fair67, the video was very informative, I like the way he explained problem areas and things that people forget to do, or overlook.

What I wouldn’t have given 30 years ago for the information at our fingertips today.

[Caveman49]

Amen!

[Groover]

I watched the whole video and I'm not even rebuilding a C4... but if I ever do someday, I'll be sure to smoke a cigar while I do it.

[fair67]

Glad you guys liked the video I will have to watch it again. However I need to figure out removing the tranny first.

[Joe Travers]

Glad you guys liked the video I will have to watch it again. However I need to figure out removing the tranny first.

1.) Remove the inspection plate bolted to the bottom of the bellhousing to access the convertor to flexplate nuts.
2.) Transmission in neutral, turn the engine to access and remove the four nuts.
3.) Disconnect battery and remove the starter.
4.) Disconnect linkages, cooler lines, vacuum line, wiring harnesses & speedo cable. Be ready to catch fluid from the cooler lines.
5.) Remove the driveshaft and cover the output shaft on the transmission or a big mess on the floor.
6.) Slide rolling jack under the transmission to support the weight, remove rear support & bellhousing bolts.
7.) Jiggle the transmission loose and pull toward the rear of the car.

Watch the torque convertor up front. Don't want to pull it out of the pump and make another big mess on the floor.
Not a hard job if you take your time and try not to spill fluid all over the place (and yourself).

Joe

[fair67]

Joe
Thank you very much I appreciate the great instructions.
Luke

[Joe Travers]

Luke,

A couple of tips, if you're working by yourself. The worst part of this job is the potential mess you can make. Nothing will kill your enthusiasm more than laying in transmission fluid.

Cut a long piece of duct tape to wrap around the back u-joint after you unbolt it from the pinion yoke. It will keep the cups from falling off and losing your needle bearings. Push the driveshaft into the transmission until it stops and lay the back end on the floor. Double up some HD garbage bags w/ drawstrings and sock the output shaft of the transmission as soon as you pull out the front yoke.

Have fun

Joe