Rear differential, installation question re: differential bearing preload....
Rear differential, installation question re: differential bearing preload....
differential bearing preload and
adjustment procedure.
Almost done with my truck, engine sounds good, can't wait to drive it, but today won't be the day.... :insetbangheademoticon:
Anyway.. I'm at the rear end, and the book seems to jump a good bit, one step is "torque bearing caps to 10ft pounds"
next its make sure bearing caps are torqued to final torque of 100ft pds...
with this in between "differential bearing preload and
adjustment procedure."
I want to get the rear perfect, so I don't have to take it apart again. when I tightened it all down it locked up. So I know I made a mistake. I marked my bearing caps and am using the same ones. As far as the "threaded adjusters" I just use a screw driver to get at those. (thought the holes on either side of the diff). I see they have the locks for those, but just curious as to how to ensure proper set-up. Though I know thats what controls the left to right movement of the differential, I'm not sure on how exactly to set it up, for best use. Can some one explain it, or point out where to find help in the FSM or online...??
I could never have done a tenth of the work I've done on this truck without this site, and I can't wait to start driving my Ram again...
Kinda confused on that one, don't see it in the FSM and the Haynes manual is junk.
I also found out that the rear brakes on a dodge ram are the single hardest component to work on, if you done your rear brakes, you can do anything...
adjustment procedure.
Almost done with my truck, engine sounds good, can't wait to drive it, but today won't be the day.... :insetbangheademoticon:
Anyway.. I'm at the rear end, and the book seems to jump a good bit, one step is "torque bearing caps to 10ft pounds"
next its make sure bearing caps are torqued to final torque of 100ft pds...
with this in between "differential bearing preload and
adjustment procedure."
I want to get the rear perfect, so I don't have to take it apart again. when I tightened it all down it locked up. So I know I made a mistake. I marked my bearing caps and am using the same ones. As far as the "threaded adjusters" I just use a screw driver to get at those. (thought the holes on either side of the diff). I see they have the locks for those, but just curious as to how to ensure proper set-up. Though I know thats what controls the left to right movement of the differential, I'm not sure on how exactly to set it up, for best use. Can some one explain it, or point out where to find help in the FSM or online...??
I could never have done a tenth of the work I've done on this truck without this site, and I can't wait to start driving my Ram again...
Kinda confused on that one, don't see it in the FSM and the Haynes manual is junk.
I also found out that the rear brakes on a dodge ram are the single hardest component to work on, if you done your rear brakes, you can do anything...
I found this on a Jeep website...
Is this about right???
TIA...
Is this about right???
TIA...
DIFFERENTIAL BEARING PRELOAD AND GEAR BACKLASH
The following must be considered when adjusting bearing preload and gear backlash:
The maximum ring gear backlash variation is 0.003 inch (0.076 mm)
Mark the gears so the same teeth are meshed during all backlash measurements.
Maintain the torque while adjusting the bearing preload and ring gear backlash.
Excessive adjuster torque will introduce a high bearing load and cause premature bearing failure. Insufficient adjuster torque can result in excessive differential case free-play and ring gear noise.
Insufficient adjuster torque will not support the ring gear correctly and can cause excessive differential case free-play and ring gear noise.
NOTE: The differential bearing cups will not always immediately follow the threaded adjusters as they are moved during adjustment. To ensure accurate bearing cup responses to the adjustments:
Maintain the gear teeth engaged (meshed) as marked.
The bearings must be seated by rapidly rotating the pinion gear a half turn back and forth.
Do this five to ten times each time the threaded adjusters are adjusted.
Use Wrench C-4164 to adjust each threaded adjuster inward until the differential bearing free-play is eliminated Threaded Adjuster Tool Allow some ring gear backlash (approximately 0.01 inch/0.25 mm) between the ring and pinion gear. Seat the bearing cups with the procedure described above
Install dial indicator and position the plunger against the drive side of a ring gear tooth Ring Gear Backlash Measurement Measure the backlash at 4 positions (90 degrees apart) around the ring gear. Locate and mark the area of minimum backlash.
Rotate the ring gear to the position of the least backlash. Mark the gear so that all future backlash measurements will be taken with the same gear teeth meshed
Loosen the right-side, tighten the left-side threaded adjuster. Obtain backlash of 0.003 to 0.004 inch (0.076 to 0.102 mm) with each adjuster tightened to 14 N·m (10 ft. lbs.) Seat the bearing cups with the procedure described above.
Tighten the differential bearing cap bolts 95 N·m (70 ft. lbs.)
Tighten the right-side threaded adjuster to 102 N·m (75 ft. lbs.) Seat the bearing cups with the procedure described above. Continue to tighten the right-side adjuster and seat bearing cups until the torque remains constant at 102 N·m (75 ft. lbs.)
Measure the ring gear backlash. The range of backlash is 0.006 to 0.008 inch (0.15 to 0.203 mm)
Continue increasing the torque at the right-side threaded adjuster until the specified backlash is obtained
NOTE: The left-side threaded adjuster torque should have approximately 102 N·m (75 ft. lbs.) If the torque is considerably less, the complete adjustment procedure must be repeated.
Tighten the left-side threaded adjuster until 102 N·m (75 ft. lbs.) torque is indicated. Seat the bearing rollers with the procedure described above. Do this until the torque remains constant.
Install the threaded adjuster locks and tighten the lock screws to 10 N·m (90 in. lbs.)
After the proper backlash is achieved, perform the Gear Contact Analysis procedure.
The following must be considered when adjusting bearing preload and gear backlash:
The maximum ring gear backlash variation is 0.003 inch (0.076 mm)
Mark the gears so the same teeth are meshed during all backlash measurements.
Maintain the torque while adjusting the bearing preload and ring gear backlash.
Excessive adjuster torque will introduce a high bearing load and cause premature bearing failure. Insufficient adjuster torque can result in excessive differential case free-play and ring gear noise.
Insufficient adjuster torque will not support the ring gear correctly and can cause excessive differential case free-play and ring gear noise.
NOTE: The differential bearing cups will not always immediately follow the threaded adjusters as they are moved during adjustment. To ensure accurate bearing cup responses to the adjustments:
Maintain the gear teeth engaged (meshed) as marked.
The bearings must be seated by rapidly rotating the pinion gear a half turn back and forth.
Do this five to ten times each time the threaded adjusters are adjusted.
Use Wrench C-4164 to adjust each threaded adjuster inward until the differential bearing free-play is eliminated Threaded Adjuster Tool Allow some ring gear backlash (approximately 0.01 inch/0.25 mm) between the ring and pinion gear. Seat the bearing cups with the procedure described above
Install dial indicator and position the plunger against the drive side of a ring gear tooth Ring Gear Backlash Measurement Measure the backlash at 4 positions (90 degrees apart) around the ring gear. Locate and mark the area of minimum backlash.
Rotate the ring gear to the position of the least backlash. Mark the gear so that all future backlash measurements will be taken with the same gear teeth meshed
Loosen the right-side, tighten the left-side threaded adjuster. Obtain backlash of 0.003 to 0.004 inch (0.076 to 0.102 mm) with each adjuster tightened to 14 N·m (10 ft. lbs.) Seat the bearing cups with the procedure described above.
Tighten the differential bearing cap bolts 95 N·m (70 ft. lbs.)
Tighten the right-side threaded adjuster to 102 N·m (75 ft. lbs.) Seat the bearing cups with the procedure described above. Continue to tighten the right-side adjuster and seat bearing cups until the torque remains constant at 102 N·m (75 ft. lbs.)
Measure the ring gear backlash. The range of backlash is 0.006 to 0.008 inch (0.15 to 0.203 mm)
Continue increasing the torque at the right-side threaded adjuster until the specified backlash is obtained
NOTE: The left-side threaded adjuster torque should have approximately 102 N·m (75 ft. lbs.) If the torque is considerably less, the complete adjustment procedure must be repeated.
Tighten the left-side threaded adjuster until 102 N·m (75 ft. lbs.) torque is indicated. Seat the bearing rollers with the procedure described above. Do this until the torque remains constant.
Install the threaded adjuster locks and tighten the lock screws to 10 N·m (90 in. lbs.)
After the proper backlash is achieved, perform the Gear Contact Analysis procedure.
THERE IS NO WAY IN HELL THOSE BOLTS CAN GO TO 110FT=LBS!!!!!!!!!!!
When I get up to say 20ft-lbs the rear end can't be moved with a breaker bar....
Damn, now I wish I had just left my truck with only three brakes... Had to replace diff, because pinion retaining bolt broke off. The entire transmission rebuild was much easier than these two days spent on the brakes and this stupid rear-end....
I have multiple bearing caps and cups. But what am I doing wrong???
I get less than .001 variance on the micrometer, so I know the diff is centered and it makes good contact with the pinion gear.
Is it really that bad to not go to 100ft-lbs???
I'm lost, I would love to finish this truck soon...
When I get up to say 20ft-lbs the rear end can't be moved with a breaker bar....
Damn, now I wish I had just left my truck with only three brakes... Had to replace diff, because pinion retaining bolt broke off. The entire transmission rebuild was much easier than these two days spent on the brakes and this stupid rear-end....
I have multiple bearing caps and cups. But what am I doing wrong???
I get less than .001 variance on the micrometer, so I know the diff is centered and it makes good contact with the pinion gear.
Is it really that bad to not go to 100ft-lbs???
I'm lost, I would love to finish this truck soon...
Registered User
Joined: Jan 2011
Posts: 26
Likes: 0
From: Swanton, Ohio
You need to adjust the backlash... Its very important to keep checking your backlash while you set the preload to 75 flbs. and tighen the bearing caps to 110 flbs. When you do the final torque I have found it changes the backlash slightly... Also you will need a special tool to adjust the bearing preload. The bearing preload must be set proper or your rearend will fail..