Hey all,

I started my diff install this weekend, thinking it would be a quick job, but try as I might, I cannot get the 3rd member into my axle housing. It's a Marlin built 8" diff with ARB locker installed. My truck is a 90 v6 4wd.

The diff seems to be getting caught up on the adjusting nut on one side and the seal housing (the disk with the protruding copper air pipe) on the other. It seems like the adjusting nut is protruding further than it should, but I haven't set one of these up myself so I really don't know. AFAIK all 8" 3rds should be compatible. Could incorrect setup be the cause? Assuming the pre-load is correctly set-up, could incorrect shims cause the adjusting nut to protrude too far?

I suppose I could grind out part of my axle housing to accommodate the extra width, but i'd must rather figure out the real cause for the discrepancy here.

 

maybe ask a tech at marlin? they are decent with product/tech support.

 

yeah I hit em up, theyre usually very responsive. Wondering if other people have run into this though, so I at least have some theory to present to them as a cause.

 

I'm sure they'll respond, but probably not till Monday.

 

Hit the crew up on the Marlin forums and someone suggested that it's fairly standard to have to grind a small part of the axle housing to clear the adjustment nut/seal housing to fit ARB lockered 8" diffs. I'll update once I've confirmed the fix for posterity.

 

This same grinding or in some cases a good wack with drift and BFH is common with e locker swaps as well.

The bolt that hits the inside of the housing on the e lockers can be swapped for an hex or even better a torx bolt head with a lower profile.

 

Reporting back: Success!

Ground down the four contact points (2.5 - 3.5 o'clock and 8.5 - 9.5 o'clock) minimally...maybe a mm or less...and the 3rd member slipped right in. In the process of buttoning it all up now. If it blows up on launch i'll let ya'll know