Changed the yoke seal at the front of the differential yesterday which required taking the driveshaft off, the pinion nut which is 1.25" socket along with the washer. Installed the new seal with the yoke and put the washer and the big nut back on. Didnt find a torque spec for the big nut. I think I read it was only 25 IN/lbs which blew me away a big nut like that is only pretty much hand tight. I proceeded to put it a few turns tighter than the 25 IN/lbs recommended online. Assembled the driveshaft u joint connections and proceeded to change the rear differential seal and drain the oil and replace both the seal and the oil. Torqued everything up. Went to drive it only like 20minutes ago and all went fine, proceeded to arrive back at my house, I rev matched (6 speed manual) comming to a stop and I heard a loud pop and then the car was making a loud and unusual sound comming to the stop. I pulled over right away in worry I blew my transmission. As soon as I go to release the clutch in 1st from a stop you hear a loud pop and the car jerks forward a bit and almost stalls. Didnt do it in reverse.

Please help diagnosing this noise and what it could be? I didnt drive it hard on that small test drive at all. It never did that in the past.

I'm starting to think since I tightened that pinion nut (the nut that required the 1.25" socket) more than I read, it could have added too much tension on the bearing behind that seal I changed at the front of the differential and it just grenaded itself.

Any thoughts?

 

You may have blown the rearend/chewed up the gears. It's very likely you altered the pinion gear depth from where it was. What you should have done before removing the pinion nut, is count the number of exposed threads past the nut, and make match up marks on the nut and pinion. Then when you put it back together, everything ends up back where it was.

 

Wow really? That's worse than I thought. Any way of confirming this? Before I go shopping for a new rear end?

 

Lift rear wheels off the ground, remove driveshaft, and turn the pinion yoke. If the gears went south, you'll feel it. Could be a coincidence and it's a transmission issue, but you want to isolate one from the other by removing the driveshaft.

 

So either way something serious has went in the car, so when I go to turn the yoke with driveshaft disconnected, and car in neutral, I would feel like some clunking or something? What should I feel when turning the yoke?

I highly dought it is transmission related. I went to move off in 1st only using the clutch to recreate the pop sound and the forward jerking motion it was doing, and I was able to get it so it wouldnt do it once or twice. Didnt try very many times after the incident happened. Also I didnt do anything different or anything I haven't done before with the transmission. Like I said I didnt drive it hard since the engine was cold.

 

You can also pull the cover off the diff and look inside,should be pretty easy to see if there's damage and metal in the oil that drains out.

 

Just replaced the seal on the cover don't want to replace it again lol but I could yes

 

I'm predicting some teeth on the ring or pinion gear having some chunks broken off.

 

Where do I buy new rear end gears then lol or just buy a new axle like a ford 9 inch or something.

 

Pretty sure you'll need to anyway,below prediction is probably correct..