Rear End Vibration

[ramthis9501]

Ever since I replaced the rear axle back in September with the 3.92 gears, I have had a vibration in the rear end. It also has a deep howling sound to it when it slows down to come to a stop. I thought it might have been the rear drums just needing turned. Had that done, but still didn't fix the issue.

This is where it gets weird. Now I get a little crazy from time to time and go fast It does fine up to 100. 100 and up, it starts to really vibrate and shake the whole truck. The fastest I can get it to is around 108-110. It will not climb any higher, just vibrates more violently.

I read that it might be the drive shaft needed turned 180 degrees, so I did that. Still didn't work. I'm now believing it is either something in the rear end or the drive shaft itself is bent a little bit because the truck I got the rear end off of was wrecked.

Also read that the drive shaft could just be to weak to hold up to the faster rpm's and force of the lower gears. I'm kind of stuck right now because I don't know what step I should take next. Replace the drive shaft, or have the rear end gone through to see if something isn't lined up right in there?

It wouldn't make sense that it is in the rear end, because the guy told me the truck only had 110,000 miles on it. Wouldn't surprise me if he lied though....

So what would you do next...?

 

[BAILEY1]

When they replaced the axles, did they change the bearings? Inner or outer. The problem you described sounds like bearings or too much slack in the new ring and pinion.

 

[ramthis9501]

No me and my dad replaced the rear axle ourselves. Nothing was changed, just swapped axle for axle. I've also heard of to much slack in the pinion, but would it do that with time and wear?

 

[BAILEY1]

Time and wear would take years if the new gears were installed properly. I would go to a proper shop and have it checked.

 

[BAILEY1]

OP. I misunderstood your post. In the first line it sounds like you also changed the gears out along with an axle. That's my mistake. I would def look at the inner and outer bearings to see if one or all has gone bad, but it still would not hurt to have the rear checked for excessive play . Sorry about that.

 

[ramthis9501]

Didn't swap gears out of the same axle. I had 3.55's in the original axle that came with the truck. I got another axle off of a 98 SS/T with the 3.92 gears.

I'll probably just take it to a shop and have them look at it. Thanks.

 

[Okiespaniel]

That chunk of metal you found when swapped the gears...might have been the pinion crush sleeve. Pinion bearings are notoriously weak in these axles and wear, abuse, or shock accentuates that.
I wouldn't be driving too fast because if it is the pinion bearing and that pinion bearing blows it will lock your rear end on the spot and you'll be in for the ride of your life.

 

[ramthis9501]

Hmm... Good point Al. Probably be best to go have it looked at. Thanks