Hey guys, I'm RIGHT at the end of my FM1/6sp/3.63 rear end swap (going all in). Everything went... Surprisingly well tbh. Except right at the end, I go to slip the driveshaft into the transmission and it goes about 75% of the way but will not go any further.

I can tell it's not going in all the way because I can see where the yoke is shiny from previous installation.

It's not going in far enough to get the driveshaft onto the diff.

I looked inside the trans, I have a camera probe, see nothing. Looks clear.

If I push it in as far as it will go currently(not even hard mind you...)it gets stuck, and I have to take a hammer to it to get it out.

I did try tapping on the rear of the driveshaft with a rubber mallet to get it to go in, did nothing (it was getting stuck before this, so it's unrelated).

If I put the car in gear, I can't spin the driveshaft, so I know it's going in at least over the splines.

I did replace the tailshaft seal, but I was extremely careful getting it out. Didn't even stick anything down or near the output shaft on the trans.

Splines look ok on both ends.

Any advice from anyone will be greatly appreciated. I'm really excited to be driving with the new stuff.


Oof, I should add my car is a 95 (not a 95.5). I'm swapping from stock clutch/5-speed/4.1 rear end.

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Look in both the holes

 

Yea I just was, it looks like the output shaft splines on the trans are twisted. Wtf? How does this even happen?

 

https://kmiata.com/collections/trans...dapter-package

 

Is your PPF cracked where that thing is welded?

 

Nah it's not. It does look like it though.

I just got the trans back out again. I can confirm 100% the output shaft is broken. It's twisted like the barrel of a gun, and it's sheared right where the driveshaft sits inside when it's bolted up to the diff.

 

Where are you located?

 

SoCal. San Bernardino specifically (that's where I live), however the car is in Apple Valley at my parents where all my tools are.

 

Maybe someone who has blown up a 6speed can send you that shaft and you can swap it.

 

I don't have the tools or expertise to do it myself.

The seller (who is a member here hence why I haven't said names) is offering a full refund. I think I'm gonna go with that and just turn around and use the money to replace the shaft. There is a great transmission shop up here by my parents. They rebuilt my little bros jeep transmission and 80k miles later it's still going great.

 

Best pics I could get.

 

Torque

 

I'm sad, no one laughed at my witty link

 

thats wild that it twisted the splines like that.

get a matching twisted driveshaft from the seller. problem solved. lol

 

Tbh, I did irl, I just didn't post anything about it. I really wish I had the money, tbh.

Hahaha yea someone else suggested that as well!

 

I'm impressed someone managed to twist those splines before breaking the gears honestly.

 

Yeah, I kinda feel like a special prize for Mechanical Anger is warranted here. I have NEVER seen the input shaft twist like that.

 

Your PPF is most definitely cracked, by the way.