Cannot seat torque converter into front pump of a C4 tranny. Please help!

DualStangs289 said:

I've tried to seat my torque converter into my C4 transmission but I can't seem to get is into the front pump. I got the TC to 'click' into place twice, over both shafts but it won seat all the way into the pump. I've tried lining up the grooves, wiggling and shaking but to no avail.

I have read many other posts about this problem and people always say 'just keep wiggling, it'll go in'. But it wont. This is the second tranny thats given me this problem and I don't now what to do.

The problem seems to be the fact that the pump gear wiggles out of place every time I get the TC over the input shaft. How do I prevent the pump gear from falling out of place so I can just slip on the TC?

Please help me! I'm desperate to get this thing on.

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Dude I'm sorry to hear you're having so much problem. My only suggestion is to turn the engine over 90 degrees and then try again with the TC.

I always do it this way, the torque convertor must not be on the engine and the transmission back from the engine, place the torque convertor on the input shaft to the trans, and turn it clockwise, it should line up with one part and slide on about an inch, then spin it faster by hand and apply a little pressure to the stub in the center of the torque convertor, and it should line up the rest of the way and slide on another inch or more. Once it is seated, turn your flexplate until the drain plug hole is visible from the bottom, and turn the torque convertor until the drain plug is in the same relationship to the flexplate, then put the transmission to the engine, or the engine to the trans, you will have to turn the engine or the torque convert to get the studs to line up, just make sure the drain plug pokes through the hole in the flexplate. I'm not a trans expert, just an old mechanic. Good Luck.

Not an expert here either but do as Rex says. I've put in a few and used to supervise a Cat assembly line and I've done it there in the engine bay for a couple shifts on around 25 of me and they are the same. Slide it on and with some pressure against the front rotate it to the right and you should hear the 2 clicks to know its locked in right. Good luck. It is the right converter for a c4 right?

I had the same problem worst case scenerio I ended up bringing it to a transmission shop they were able to seat it for me and put a bolt/ bracket in to transport it most places will be happy to help and wont kill you on price for a few min of their time

there are two splines on c4 a early and late one 24 and the other is 26 spline

Spline count for everything is 24. And all the numbers match

Thank you all for your responses.

The TC and the transmission numbers match so I know it's the right one. I've done measurements on the shafts which all check out. IMO there is no reason why it wont slip on the rest of the way.

I think I'm just gonna break down and take it too a shop... I really don't want to because I'm the type of person to do everything myself.

I hear that the small shaft can be installed backwards in some cases, and all you have to do is remove it and flip it around. Is this true?

Problem solved!

I called a transmission shop and they gave me some advice.

The input shaft was installed backwards. There was about a 1 inch gap between the input shaft splines and the outer shaft splines. Apparently the input shaft needs to be pushed all the way into the outer shaft so that no shaft is exposed.

It wouldn't go all the way in so I took some vice grips and grabbed the input shaft (carefully). Then I gently tapped on it with a brass hammer until it slid out. I then flipped it around and shoved it back in. SUCCESS! The input shaft went in all the way.

Then I shoved the TC on and it went on all the way, without any problems at all!

IN A NUTSHELL: If anyone cannot seat their TC no matter what you try, check to see if your input shaft is installed correctly. There should be NO shaft exposed, only the splines.

DualStangs289 said:

I called a transmission shop and they gave me some advice.

The input shaft was installed backwards. There was about a 1 inch gap between the input shaft splines and the outer shaft splines. Apparently the input shaft needs to be pushed all the way into the outer shaft so that no shaft is exposed.

It wouldn't go all the way in so I took some vice grips and grabbed the input shaft (carefully). Then I gently tapped on it with a brass hammer until it slid out. I then flipped it around and shoved it back in. SUCCESS! The input shaft went in all the way.

Then I shoved the TC on and it went on all the way, without any problems at all!

IN A NUTSHELL: If anyone cannot seat their TC no matter what you try, check to see if your input shaft is installed correctly. There should be NO shaft exposed, only the splines.

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Good deal man glad you got this taken care of. That is a problem I had never heard of before. :bigthumbsup

I'm having the same problem, my trans shaft is showing and i can't get it to seat all the way back in. But it was working fine before then so i don't know if I shoudl remove it and spin it around and put it back in?

Kepaloha, please start a thread with your problem, this thread is almost 3 years old.