9", ARB and 4.86 gear clearance issues

[trailpsycho]

I am trying to see how many people have had problems with gear clearance issues with 4.86 or similar gear sets when installing a locker, especially an ARB. My installer clearanced the pinion bearing support area as is required with the ARB (and Detroit from what I have heard, so the ring gear/ locker assembly can sit in the case. Now the case webbing/support is right in between the gears of the ring gear. We took measurements of the stock carrier and the ARB from the bearing to the edge of the carrier and they are the same. The 4.86 ring gear is somewhere between 1/4 and 1/8 of an inch thicker than the original gears, so at least 1/8" of that bearing support/webbing on the carrier needs to be removed. It seems excessive. I talked to one guy who does gear set ups for one of this sites sponsors (Bronco vendor), he said it was pretty normal, just remove as little as is required. I am still waiting to hear back from Randy's Ring and Pinion and Mike at Complete Off Road. My installer said he's never seen one need that much clearancing before.

Does anyone here have any experience with a similar setup and how you were able to solve it? Pics? I will take pics once we figure it out, so I can show everyone what was required. It just seems a little much. Thanks for any experience or advice you can share.

John

 

[welndmn]

Yes, they all need to be ground down, 1/8 sounds about right, I never measured, but set up tons of them.

 

[trailpsycho]

Thanks, I got a call from Julie (Mike) at COR and he confrimed as well....you make #5...actually had two people say NO, no way...so I was a little concerned...I dont think those people had ever installed such a large gear set before, so add a grain or two of salt. A little freaky to need to grind that much, but at least now we can move forward. Got the assmebled D44 rustbulleted and top coated yesterday...the RB-probably due to my impatience leaves a bit more texture than I would prefer, but its very hard adn coats/fills very well....now on to the 9" housing. Thanks Welndmn.

John

 

[bax]

Yes, they all need to be ground down, 1/8 sounds about right, I never measured, but set up tons of them.

Like said above, they all need some grinding. The steeper the gear the smaller the pinion gear, the more grinding you must do. Thats what you get with a stock case. Some of the aftermarket cases don't need this much grinding. They are cast with the clearane / improvement built into them. I always used N cases for my set ups and always had a fun time grinding, checking, grinding, checking. I could not find an N case for my current project so I bought a Strange Sportsman case. I did very little grinding, very happy with the outcome. Good Luck

Bax

 

[truehi9]

This may be a little late but might help. The 31 spline ARB was changed so that the outside of it is the same size as the 35 spline ARB. If some one told you they didn't have to remove much material they were maybe used to the old style, smaller 28/31 spline ARB.

There are a few pics on here www.truehi9.com of an ARB installed in a 9 inch, the 9 inch is high pinion but basically a mirror image. The 3rd pic down maybe the only one of use to ya but might help.

 

[trailpsycho]

Thanks guys, if I had known it would need so much clearancing, I probably would have gone with a Strange case. Hopefully, this will hold up. Thanks again for the pics and feedback.