Driveshaft not sliding in...

Okay, after tearing the cats back out to move the O2 wiring from the left side of the transmission to the right, I got all the exhaust buttoned up.

Went to slide the driveshaft in, and it went in all of an inch. Full stop. I didn't go to the back of the shaft and try to knock it in...just took out all the crossmember bolts in advance of removing it to get to the tailshaft housing to see what might be holding me up.

Other than that, it's ready to go! Anti-squeaked the front discs, new gaskets on oil cooler adapter (that paper gasket is a bitch).

It should slide in with little effort. Make sure the universal joint has flex in the right direction. You may be getting a little resistance from the shaft seal.

I agree with Fred, it should go in place fairly easily. Hopefully you got everything in the right place during the rebuild...

Verify there are no burrs or debris on the tailshaft or inside the yolk.

Went and Googled the phrase "driveshaft doesn't slide in" and came up with a dozen results, most having to do with tail housing bushings either with nicks or burrs, or becoming undersized when driven in to tail housing. Before I quit working on Tuesday, I pulled all the bolts out of the crossmember, and mount, just need to release the exhaust to cat bolts...then I can get at the tail housing, and fit to yoke. Never thought of doing that while building transmission up. Sherlock, put that in yous stickies! LOL

Took some emery cloth and massaged tail shaft bushing. Put some Trans-Gel on yoke and slid it in to end of bushing, then took a rubber mallet and hit the tail shaft housing at 90 degree turns...saw that in the trans rebuilding videos. Seats the bushing better, I guess.

Got everything bolted up, seems that the trans likes to be turning when adding fluid...leaked about 2 quarts while filling up. Started engine, filled the rest just fine.

But when on ground, no reverse. Nuthin'. Forward gears (car parked in front, so can't move) seem to work. Edit: no OD, 3rd and 2nd kinda work, but slip pretty bad. No 1st. Pretty sure this is coming back out.

This is an all new home rebuild.

I'm stumped.

I know at the lube shop I used to work at we would cycle the transmission through the gears as we filled it when we did a drain and fill.

so best case I can think of is with the car sitting gradually cycle it through the gears at idle several times before checking the fluid again.

Think I may have found the problem of no moving...boost valve came out of pump. Found all the parts except for the snap ring, which might be in the filter, I hope. Otherwise, it may have gotten sucked into the pump.

And don't use those rubbery-plasticy pan gaskets. They leak.

Follow up...snap ring was indeed inside the filter. Much better than inside the transmission in some random location (like inside the front pump).

Yay.

If the snap ring came out once, the likelyhood of it doing again are high unless you are sure you had it in wrong. Slightly bent, lost tension, damaged groove, burrs in groove all could cause the ring to come out. Hopefully, you can find a new one, as these transmissions are very common and the rings are likely in all the kits for them.

I found a new one at the hardware store...looks very close. Also have some coming from Amazon, but they're all metric. We'll see. Otherwise it's change the front pump time...