Drive shaft/half balancing

[Gregory G.]

I rebuild my rear suspension a couple of months ago and replaced all the u-joints. I recently read that the drive shaft was balanced with the yoke. I did not mark on which side or orientation the yoke was. Does this mean that it will have to be rebalanced? Does it make any difference in what orentation/rotation od the drive shaft to the rear? How could I possibly have it balanced with the rear?
The half shafts do not have weights were they balanced and does the orientation of them make any difference.
Why would GM balance an assembly and not put perminate aligen marks for assembly/reassembly?

[John H.]

Re: Drive shaft/half balancing

Greg -

The main driveshaft was balanced by the supplier as an assembly with the FRONT yoke attached; I'm not sure whether the paint mark at the rear U-joint end (and the paint mark on the diff yoke) denoted high/low runout or high/low balance marks, but they were originally aligned at assembly at St. Louis. The half-shafts were never balanced by GM; they're short, and only rotate at 1/3-1/4 the rpm of the driveshaft.

[Gregory G.]

Re: Drive shaft/half balancing

I guess I have nothing to worry about with the half shafts. I will have to do a trial and error to get the drive shaft balanced or have it rebalanced. If I have it rebalanced can it be done without the yoke and then have the yoke done seperatily?

[John H.]

Re: Drive shaft/half balancing

Greg -

Check with your driveshaft shop/balancer to see what their capability is.

[Mark #28455]

be careful with balance weights

A lot of shops weld round washers to the shaft for balancing. My originals seemed to all use rectangular sheed steel. Be sure to specify what you want - don't assume!
Good luck,
Mark