Drivetrain Differential Issues?

[jsw81]

Took the mustang out for a short drive today. I got on it a bit in second gear and shifted through 4th. Looked behind me and lots of whiteish smoke out the back and has a burning smell almost like clutch but not quite. The rear locked up for a couple seconds and now has a bad vibration I can hear and feel through the shifter. I was able to limp it home. Didn't see any leaks from the rear.

Is it possible I broke an axle or sheared off the splines? Not sure if I would still be able to move if that was the case. Or possibly broke a ring or pinion tooth? It has 3.73 gears and a newer ford racing differential according to the previous owner.

Or is the transmission toast? I kind of felt like I couldn't shift it for a sec. I know it has a leak at the tail shaft. So maybe the input shaft went and the smoke is tranny fluid??

 

[rd]

You might as well just jack it up and pull the rear axle cover. It should be apparent quickly, and probably not a big deal to fix.

 

[jsw81]

Yeah when I get time (which I rarely have)I will pull the cover. A friend of mine seems to think it may be the input shaft. Just checking to see if anyone has had a similar experience on here.

 

[pissedoff92]

Cant say I know much about tranny's yet. I'm rebuilding mine in the next few weeks. But I do know about rear ends. Unless you have C clip eliminators you didnt break an axle. 98% of the time you break an axle on a hard launch not just getting on it in second. It is possible you stripped the splines but not likely. Check your tranny fluid and go from there. Even though alot of people are scared of rear ends theres not much to them, its just alot of precise measurements. Once you open it up let us know what you find. If you broke an axle it would have walked out on you and it would have made a hugeeee mess. Let me know what you find and go from there. If the rear end bound up it could be anything from a pinion bearing to the actual carrier bearings but you will able to see evidence of either when you pull the cover. I wouldnt rule out the input shaft bearing either. If your running a NWC t5 they are quite a bit weaker than the world class ones if you ask me.

 

[ratio411]

Could have broken a spider gear in the diff.
I had similar symptoms when that happened to me with an 8" rear end.

I don't know that I felt it through the shifter though. That part of your symptoms bothers me.
Could be in the tranny...

I hope it's something easy.
Good luck

Edit: Input bearing will usually cause your tranny to pop out of gear when you move.

 

[jsw81]

Update:

Found a little time this evening and pulled the cover on the diff. Everything looks fine, no metal broken anywhere. Everything spins without issue.

Next thing I am going to check is the rear drums. The whole smoke show I had and friction smell makes me wonder if it's brake related. Really scratching my head here guys....any other suggestions or things I may have missed looking at the diff?

 

[pissedoff92]

Look realll close at the spider gears. I just blew mine apart in my truck the other day. If you can get a magnet mount dial indicator it wouldnt hurt to take 5 minutes and check your backlash. Then I would say work your way outward to the brakes and forward to the tranny. Is the tranny leaking at all? And it could be something simple in the brakes like the tiny cable that goes along the shoe and connects to the top post. I worked on a buddies truck whos cable was old and stretched alowing the shoe to angle and lock up against the drum while driving forward

 

[jsw81]

The transmission has a tiny leak coming from the tail shaft seal. Not sure if it's just a bad seal or what. It seems to shift fine though.

I will check the backlash. I still have the cover off so I will before I reinstall it. I looked as much as I could at the spider gears and I don't see anything wrong. I will take another look in case though.

Tonight I just took the rear drums off and it's rusted bad in there. The right drum was very hard to get off, had to use my sledge. A bunch of black brake dust fell out on that side and was in the drum. The left side came off without issue although it's rusty in there. I am going to replace everything in there since it almost looks like original parts.

Also a thing to note is when I picked up this car the e brake cable that comes from the lever itself was broken. I replaced that but never thought twice about the rear cables going into the drums. I am wondering if that right side was binding somehow. I believe there is a good chance that this is the problem. I ordered a set of cables just in case. This car has 160,000 miles on the body so these things are bound to go bad sooner or later.

I will update once I rebuild the rear brakes and such. Thanks for the comments and suggestions.

 

[pissedoff92]

Yea and even if you dont run an E brake those cables have to be hooked into those brackets or the brackets can wedge themselves into the drum. causing something like you explained

 

[jsw81]

Ok, so I replaced the rear drum brakes and the e brake cables. The e brake works much better. However, I still get the vibration sound. I found that it only happens on decel. If I put it in neutral, the noise goes away. Is this perhaps a transmission or clutch issue?

I did get on it and didn't notice any weird smells. Just burnt rubber and tire smoke...