BLOWN REAR END??? HOW CAN I TELL

[87MC_SS]

I hav a 87 MC SS, I was cruising from work when I felt a bang under my seat and seen something fly from under my car, I pull over and my drive shaft was hanging. The U-Joint between the axle and shaft had snapped in half. Later when I loaded it on to my trailer... I thought everything was okay until I tried to roll it off backwards it would lock up but would roll forward with ease... I lifted the rear in up while on the trailer and took a look at the Dif. on both sides you can see a grey-ish blue tinge in the front corners of. While the rear end was off teh ground I spun the tires... When spun forward both spin the same direction. When I spin one backward the other spins forward and it has a loud clanking noise... almost like something is gettin caught on the ring gear. Can anyone give me an idea of what it might be???

 

[trog]

time to pull the cover...sounds like your lock pin broke 😢

 

[Chris Van]

Either way... The cover has to come off to tell what exactly is broke. Good luck because it doesn't sound good.

 

[jrm81bu]

Could have even broke the head off the pinion gear. That will allow it to turn one way but not the other.

 

[pontiacgp]

That sounds like mine two nites ago...my spider gears on the pinion shaft grenaded. I was still able to drive it up to the lift cause the gear bits locked the side gears I didn't know that of course until I took the cover off...You may get lucky and if it's just the gears you can replace them and you'll be back on the road but with the sign of overheating it is probably something else. It sounds like you may have run it low on oil. For the drive shaft tho it is probably twisted so you should take that in and get it checked out. If the yokes are still in good shape it's not too expensive to get a new tube installed and balanced....

 

[87MC_SS]

The drive shaft is good. The yoke is fine. Besides a few nicks from it spinning on the concrete lol But yeah I will start the tear down tomorrow and post some pics. I guessed it was the pinion and ring gear but we'll soon see! I dont want to put to much into it because during the winter months I planned on putting in 4.11 and disc brakes. So if it is just the pinion and ring gears whats the best and worst outcome price wise??

 

[pontiacgp]

if the drive shaft broke a u-joint I would put money on it the tube is twisted..you can pick up a crown and pinion for anything from 75 to 150. If the pinion was removed from another rear end 99% of the time the shim will work for another rear end but you'll want to check it anyway

 

[87MC_SS]

if the drive shaft broke a u-joint I would put money on it the tube is twisted..you can pick up a crown and pinion for anything from 75 to 150. If the pinion was removed from another rear end 99% of the time the shim will work for another rear end but you'll want to check it anyway

Okay, I will have the drive shaft checked out Monday, and start the tear down.

 

[1badbu]

my spider gears on the pinion shaft grenaded.

pontiacgp will be correct.I've bombed several 7.5 spiders :shock:
Also between my Dad and I we ate up two sets of ring and pinion gears in those tiny 7.5's.

 

[larryo454]

1 wheel peel kills the spiders and pin and the crown and pinion big time.