Carrier bearing noise after lowering

[smackhead61]

Recently completed a static rear end drop on my 66 LWB using 5 inch drop springs and 2 inch blocks. I replaced the OEM pan hard bar with an adjustable one from Early Classics and installed a bolt in notch. I also installed a 5 lug rear end from a 1972 1/2 ton. The front end is currently bagged and has 2.5 inch drop spindles. The truck still has a two piece drive shaft.

The issue I'm having is the carrier bearing is making a "whumping" sound as soon as the truck starts to roll (carrier bearing is also new). Do I need to check pinion angle and possibly use shims? Is it dropped too much in the rear and do I need to remove the blocks? I am completely stumped at this point and any help would be appreciated, Thanks!

[PGSigns]

That is a lot of static drop and it will affect the pinion angle a good bit. You will need to see what it is now and how steep the drive shaft angle got. I did less drop on mine and if memory serves me it took a degree and a half to get the pinion back down. I machined a 1/2" shim to go under the center support bearing and checked to see that I still had about 1/2 a degree of working angle in the front u-joint. then matched the pinion angle to the front ujount on the rear shaft. Spicer has a really good section on there web site for setting the drive line angles.
Jimmy

[cdowns]

did u check the length of the driveshaft to see if it is too long and binding up aftyer the drop

[smackhead61]

I'll check the pinion angle and am considering removing the 2 inch blocks and just leaving it a 5 inch drop. I will also check for binding due to the amount of drop on the rear. Thanks for the info!

[smackhead61]

Originally Posted by cdowns

did u check the length of the driveshaft to see if it is too long and binding up aftyer the drop

I'll check the length, thanks hadn't thought of that.

[smackhead61]

Originally Posted by PGSigns

That is a lot of static drop and it will affect the pinion angle a good bit. You will need to see what it is now and how steep the drive shaft angle got. I did less drop on mine and if memory serves me it took a degree and a half to get the pinion back down. I machined a 1/2" shim to go under the center support bearing and checked to see that I still had about 1/2 a degree of working angle in the front u-joint. then matched the pinion angle to the front ujount on the rear shaft. Spicer has a really good section on there web site for setting the drive line angles.
Jimmy

I pulled the 2 inch blocks out tonight and it drives like a charm. No more whumping sound, Thanks again for the info as I may need to still set the pinion after driving it around some more and at different speeds.

[PGSigns]

The blocks will move the rear end forward due to the design of the trailing arms. You drive shaft may have been bound up at the slip joint.
Jimmy

[smackhead61]

Originally Posted by PGSigns

The blocks will move the rear end forward due to the design of the trailing arms. You drive shaft may have been bound up at the slip joint.
Jimmy

Took the old girl out for a drive last night and it works just fine! Thanks for the insight Jimmy.

[PGSigns]

That's cool, time to enjoy the new stance.
Jimmy