PDA

View Full Version : ARB back lash with used gears


whitexj98
August 19th, 2017, 15:52
So I'm putting an ARB in my 8.25. I previously geared to 4:56 7 years ago.

Anyways I checked backlash and turning torque before disassembly. Back lash was .009-.010".

I have the arb installed and back lash set right at .009-.010".

I have new carrier bearing installed so my question is should I go a bit tighter on back lash or setup exactly as I took it apart? I'm just wondering if back lash will open up a bit...

jeeptec
August 19th, 2017, 17:11
The new bearing will break in a bit. When I did my Arb it measured .009-.011 with the old bearing and stock carrier. When I put it back together I set it at .006 -.007. It is quite and no problems. Set your Carrier bearing preload to 70 ft lbs. if you not have the proper tool you can make one using a VW axle nut and weld it the an old socket that is 1/2 drive or 3/8 and use a long exstention through the axle housing.


Sent from my iPhone using Tapatalk

trippled
August 19th, 2017, 17:40
As long as the preload is set correctly, your bash lash should not change or there is a problem somewhere. New bearings do loosen up,but that is why there are specs for setting preload on new and used bearings.

jeeptec
August 19th, 2017, 18:40
The 8 1/4 has screw adjusts and yes you can change the backlash and preload and the bearings if not done correctly. When I set my back lash I try set get it real close with the ride side adjuster just right against the bearing and torque on the left adjuster. This will bring to backlash to specs and the bearing preload to spec,s . Been doing it this way for 32 years at the dealership.


Sent from my iPhone using Tapatalk

whitexj98
August 19th, 2017, 19:28
The new bearing will break in a bit. When I did my Arb it measured .009-.011 with the old bearing and stock carrier. When I put it back together I set it at .006 -.007. It is quite and no problems. Set your Carrier bearing preload to 70 ft lbs. if you not have the proper tool you can make one using a VW axle nut and weld it the an old socket that is 1/2 drive or 3/8 and use a long exstention through the axle housing.
Sent from my iPhone using Tapatalk

Funny you say that, I also play with VW rails and made my adjuster tool with a VW stub nut. I have both adjuster at 75 ft lbs per the FSM with the back lash at .009-.010. I may set it a bit tighter as you suggest.

jeeptec
August 19th, 2017, 19:36
Yea one of the guys I worked with in the 80's made mine. We couldn't find the shop one. So we improvised. He gave it to me when he left the dealership.


Sent from my iPhone using Tapatalk

trippled
August 19th, 2017, 22:11
The 8 1/4 has screw adjusts and yes you can change the backlash and preload and the bearings if not done correctly. When I set my back lash I try set get it real close with the ride side adjuster just right against the bearing and torque on the left adjuster. This will bring to backlash to specs and the bearing preload to spec,s . Been doing it this way for 32 years at the dealership.

Wasn't disputing what you said just saying that if preload is set correctly with backlash the backlash shouldn't loosen up. I agree tho I like my backlash on the tighter end.
Sent from my iPhone using Tapatalk

Wasn't disputing what you said. Just saying that backlash shouldn't move if the preload is set correctly. I agree and like my backlash on the tighter end.

TRAILREADYXJ
August 20th, 2017, 12:34
I set these to .007" when new, however I like setting used gears back up to what it measured before removal as long as it's within spec.

I also recommend setting the carrier preload on the tight end, ARBs in 8.25s tend to spin the seal housing unless there's significant preload on the carrier.

md21722
August 21st, 2017, 15:38
If memory serves me correctly, 75 ft-lbs is the absolute minimum the side adjusters should be torqued to. The idea is to keep tightening them until they stop moving. May depend on the axle, but 125-150 ft-lb is not out of question. It's difficult to put too much preload on the carrier bearings. If there isn't enough preload, things will spin and you might be getting a new axle housing too.

whitexj98
August 21st, 2017, 19:25
I set back lash to .008 and around 100 foot pounds if not a little more on the adjusters.

http://i.imgur.com/0uRopKT.jpg?2