I have a 2004 H2. I had my front and rear gears changed from the stock 4.10 gears to 4.88's in the front and rear. Ever since the change I have developed a vibration at 75 mph and higher. The guy at the shop that put the gears in rode with me and said that the vibration is not a result of the gears. Ever since then I have been trying to chase down the vibration. I have replaced almost everything I can think of. Four new tires, both front wheel bearings, new front CV axle's, new front drive shaft, new u-joints in the rear drive shaft and also had it rebalanced. Everything that I have done so far has not changed the vibration that i'm feeling. If anyone has any thoughts or suggestions i'm open to anything at this point??

 

New front driveshaft- was it balanced or you just assumed it was good.

All your drivetrain up to the gears is spinning a good percentage faster now than stock. Stock balanced parts are **** any time you are moving parts faster than intended. Ever had your rig over 85-90 before the swap, if so was it smooth?

You can pop off the diff covers see if you see any clips laying in the bottom.

Last resort yank one of the driveshafts and go for a quick spin, should figure out pretty quick if its coming from the front or back. I'd probably pull the rear.

Good luck!

 

I didn't add in my original post but my hummer has a 6 inch fabtech lift and sitting on 37" Toyo open countries. The new front drive is from fabtech that comes with the lifts and so I just assumed the new front drive was balanced.

I never ran it up past 80 mph before the gear change so I don't know if the vibration was there before or not?

Can you pull one of the drive shafts and drive it with it being a all time four wheel drive? I figured the computer would act stupied if I tried that!

 

yes I know the date of this thread, but was the pinion angle check?