Rmodeler

I've ask this question before and have done changes over the last couple of years. Everything from the u-joints(6), trailing arms complete with bearings, and rear end have been changed, another words all moving parts. I realized the rumbling noise I originally heard is still there, but maybe a little more pronounced. I'm beginning to wonder if the noise that I hear could be a bad bearing in the trans(700-R4) somewhere. The noise I hear is about the speed of the drive shaft turning. There is too much wind noise with the windows down, so you don't hear it then. I can only hear it at slower speeds(less than 30). Any ideas?

MelWff

Only a sound no vibration? Have you tried disconnecting the drive shaft and rotating it 180 degrees and reconnecting?

hugie82

It's rare but there is a tailshaft bearing in a 700R4. The other problem is the pinion bushing. It's very sensitive to the pinion angle it's set at. If you're 1 degree off it will rumble. A quick test is under acceleration does it get worse or better. If its better, you have to shim the pinion up and the opposit if it gets better on down shifts.

Rmodeler

The rumble was there before I changed the rear end(2.87-3.55). It seems that only leaves possibly the tailshaft bearing, which is doubtful. May just have to live with it, do some more checking when I'm not driving it this winter. Thanks for the suggestions.

cv67

Had something like that under harder accel only it was the little dampner thing on the front of the driveshaft.

on my A body have had the tailshaft done pinion bearing new tires still does it just live with it. (think its the tire tread runout)

Rmodeler

Residential street, coasting at 30mph, whether in gear or neutral. All 4 tires new this summer.

jdp6000

Have you eliminated the emergency brake? Pull up on it a bit next time you hear the noise.

Rmodeler

Both trailing arm assemblies, including rotors/e-brakes, have been replaced. Rumbling was prior to this.

wombvette

Do you have a lot of negative camber in the rear, or a weak spring?

hugie82

If the rumble was there before the gear swap, it's very possible your pinion is in the same position causing the same rumble.
I had to play with the torque on the pinion bushing bolt because it was too tight and tipping the pinion down too far....

Rmodeler

Those are some things I need to look at this winter. The back end sets about 1 1/2" high and the front sets about an 1" low, which I want to change before getting a complete 4 wheel alignment, this might help some of my problem.

Advanced24

Bad Front wheel bearing.. Makes noise with little vibration when bad..

Aussie79

You are looking too hard, check your rear transmission mount, they are cheap, replace it anyway. The noise you are hearing is normal noise that is being transmitted to the cabin, you have replaced and checked everything and it isn't getting worse, like I said, normal noise that you shouldn't be able to hear.

Rmodeler

Another place to check. Maybe it's time to go drink that cup of coffee or beer. That does wonders!!