djloc79

During a recent visit to the dyno shop, I broke/bent/twisted my driveshaft. When I went under the car for repair, I found other parts damaged. The tail housing cover was in 2 pieces. Also I noticed a crack in the cover area around the output shaft just behind the tail housing cover. Not sure what that part is called. My question is how should I go about repair? Is the cracked part a separate part that can be removed and replaced or is it part of the full outer cover? Any help would be greatly appreciated!!

djloc79

Close up of crack

djloc79

Driveshaft slapped the wall inside the driveshaft tunnel. I think that's what caused the crack. Probably was a pretty violent side shock to the output shaft.

Monzsta

Hate to say it but you're in for a case. It's all one piece back there. Might want to replace the output shaft as well. Looks like it took a beating and might be bent.

JoeNova

Step 1: Remove 4L60e
Step 2: Insert 4L80e
Step 3: Win.

mrvedit

Yeah, the trans case is toast.
I have always been very satisfied buying large parts from ebay seller "powertrainpartsplus". They have a few late-model 4L60E cases available right now for $60 plus shipping. Output shaft is $33. They also have tail housings.

You should try to determine what broke first - was it a U-joint?
I have heard of the torque arm cracking the tail housing which might have started a chain reaction.

If you are looking at 600+HP in the future, JoeNova's suggestion should be seriously considered; there are lots of threads here on that subject.

djloc79

From the looks of it, the problem started where the stock torque arm attaches to the tail housing. I think it was because of worn bushings in the connection point. The clasp type mechanism. It was an original piece that I didn't change when I did the conversion. The car had 280,000 plus miles on before I swapped the 3800 for the 6.2. I'm just imagining that the worn bushing gave more than it was suppose to which allowed the rear end to reach a dangerous pinion angle which caused the driveshaft to fail. Could be wrong.
does that sound possible?

mrvedit

I don't own a car with a torque arm and therefore cannot give you an experienced answer. It does sound "possible"; in any case repairing/replacing the driveshaft, trans case, trans tail shaft, torque arm and bushings should get it fixed. Of course all that is a very expensive fix.

jimmyblue

iTrader: (11)

The stock steel driveshafts are prone to this, especially
when overspun (anything over 2.73 gears got aluminum
driveshaft from the factory). Don't know how a V6 drive
shaft relates to what came behind the V8 with 2.73s,
but expect no better.

Cole Train

iTrader: (30)

wouldn't the steel be better than the aluminum ones?

jimmyblue

iTrader: (11)

A well engineered steel driveshaft would be better.
A "cost engineered" one, plenty of examples say is
not.

Cole Train

iTrader: (30)

Damn because my car just took a **** on the aluminum shaft and was gonna throw in a steel one i had here.

mrvedit

I just had a custom aluminum one made by shaftmasters.com (local to me, but recommended elsewhere on this site). They said it is good for 3000 ft/lbs which equates to 1000 ft/lb engine and a 3.0/1 1st gear trans ratio.
The car is super smooth with it; I suspect my previous custom steel one was a bit out of balance. Cost about $325.

ez2cdave

Custom Chrome-Moly driveshaft from Strange Engineering . . .

http://www.strangeengineering.net/dr....html?limit=48