Wheel bearings

[larryj]

91 IC W250 rebuild breaks 4X4 front wheel bearings

How do you set the pre load for the front wheel bearings.

Dana 60

need to know same for the rear axle also.

 

[JHumphries]

Front
To install:

1. Carefully position the hub and disc assembly on the spindle.
2. Install the outer bearing cone and roller, and the adjusting nut.

The adjusting nut has a small dowel on one side. This dowel faces outward to engage the locking ring.

1. Using a hub nut wrench tighten the bearing adjustment nut to 50 ft. lbs. (68 Nm), while rotating the wheel back and forth to seat the bearings.
2. Back off the adjusting nut approximately 90°.
3. Install the lock ring by turning the nut to the nearest hole and inserting the dowel pin.
   

The dowel pin must seat in a lock ring hole for proper bearing adjustment and wheel retention.

1. Install the outer lock nut and tighten to 50-80 ft. lbs. (68-108 Nm). Final end-play of the wheel on the spindle should be 0. 001-0. 010 in. (0. 025-0. 25mm).
2. Assemble the hub parts.
3. Install the caliper.
4. Remove the jackstands and lower the vehicle.

Rear
ADJUSTMENT
Full-Floating Model 60 and 70 Axles

1. Raise and support the rear end on jackstands.
2. Remove the axle shaft.
3. Remove the lock ring and loosen the adjusting nut.
4. While rotating the wheel, tighten the adjusting nut to 120-140 ft. lbs. (162-189 Nm).
5. Back off the nut <SUP>1</SUP> / <SUB>3</SUB> turn (120°). This will provide 0. 001-0. 008 in. (0. 0254-0. 2032mm) end-play.
6. Install the lock ring onto the spindle keyway.
7. Install the axle shaft and new gasket.

 

[JHumphries]

The front axles are known for backing off. The stock setup is not very good.
I replaced mine with these
X-Lock Locking Spindle Nut
They are listed for the front, but I called them and they said to leave out the thrust washer if necessary to make room in the rear.
These nuts can not back off!

 

[DVolk]

I had to buy new nut kit once but i have never had them ever back off on me use the proper socket for the lock nut and it will stay put !!!!!!!!!!

 

[TBartlett1]

I purchased my first W250 in 1990 and drove it 235k until rust forced me to retire it.

I then removed the running gear for spares & scrapped the body.

I have owned a total of 5 CTD's and currently have 3.

I have had front & rear hubs off many times for service and have always adjusted the wheel bearings for zero play. Wheel bearings are not a special application.

Tapered roller bearings are in fact designed to be preloaded for zero looseness.

A loose bearing can in-fact cause premature seal failure!

GM's 14 bolt full floater specificately states that the wheel bearing's be adjusted for zero looseness.

Making the final adjustment of the bearings with the wheels & tires on permits you to better feel any looseness and eliminate it when making that fine adjustment.

The jam nut set-up used in the front requires special care when adjusting because when you torque the outer jam nut against the inner nut it puts additional load on the bearing so it may take several attempts to get it right. You need to set the inner nut a bit on the loose side because when the outer jam nut is tightened it will eliminate the looseness.

As far as the adjustment nuts backing off or tighting & destroying the bearing a bit of loctite will eliminate that problem. I also use Loctite on the rear nylock nuts used in the old 1st Gen's.





Tim