LS6427

iTrader: (2)

So, I just got my car back with my new AES 390ci. Everything is good except when I gradually accelerate to 40-50mph and faster on the highway....I have a WAW-WAW-WAW-WAW constant sound and vibration throughout the car.

There's no sound or vibration below about 30-40mph.

Obviously the shaft was removed with the tranny to do the new engine install......

Des a shaft sometimes need to be rebalanced after its removed......?

I'm trying to track this vibration down by ruling things out first.

Thanks.....

.

Bob@BruteSpeed

iTrader: (16)

Try pulling the driveshaft out and rotating it 180 degrees. Bob

666ws6

iTrader: (3)

I had the same after I did my own gears the first time... I didn't watch the drive shaft position and orientation into the u-joint so when I reinstalled it... I had bad vibes.

I put the car on jacks in the back and leveled it and slowly rotated the rear wheels in neutral to see how far off the DS was. Then just adjusted in the u-joint.... Easy fix.

LS6427

iTrader: (2)

So it has to go in the same way it used to be...?

Or it can vibrate...?

.

LS6427

iTrader: (2)

What do you mean....you spun the tires and watched the DS.....

Can you see a wobble as the DS spins or something else to look for......?

But either way, did you do what Bob said above? How did you adjust it?

.

Bob@BruteSpeed

iTrader: (16)

It can vibrate at times. Bob

Blackpanther99

iTrader: (8)

If it keeps vibrating just get it re-balanced.

666ws6

iTrader: (3)

Actually, I used a pinion depth gage on the shaft as I slowly rotated the tires... So it was easy to see that it was "lopsided" if you will.... Or off-center.