V6 spool into a "4 cyl 3rd" and 529 gears
(20 low res pics loading)
JAN 16 2006

Damen is local to me and lives in the Mesa area. This is his trail rig...kinda hard to tell but this was an 85 Runner and now has a 91 pick-up body on it. He was on a trail in the Sycamore area similar to the pic above and, un-explainably, a rear axle frags....which takes out the carrier bearing....which explodes the Detroit Locker...which destroys the PRECISION brand 529 gears. An expensive break but at least the 38.5x14.50 tires survived...so did the double transfer case and the 22RE.

So Damen brings over a V6 spool and an old 410 3rd member with some Yukon 529 gears and wants to know if it's even possible to make the spool work in the 4cyl carrier. I said no problem....all I need is a set of "conversion bearings" that I just happen to have.

The only thing missing is a new set of pinion bearings but the rig is mostly trail so Damen just preferred to re-use them once again.

These are the conversion bearings needed to adapt a V6 case(spool or open or Detroit Locker) to a 4 cylinder 3rd. These bearings have the larger 50mm inside diameter to match the V6 cases. Everything else is business as usual. Here's another place that these bearings can be ordered from...Completeoffroad.com.

A minor thing but glad I noticed it...with the bearing pressed on tightly there was still a small gap... this was due to the inside curvature of the bearing not matching the slope of the spool bearing surface.

For me, the easiest way to fix this was to use the dremel tool and remove some material until it does seat flat. This took 5 minutes per bearing.

I checked the spool for run-out with the dial indicator and found it to be less than .001" which is excellent.


I've set up many of these Yukon ring and pinions that have the "304" on them....they set up very well.

The ring was a very tight fit onto the spool. I used 4 of the ring bolts to pull it on evenly.

With that out of the way, now it's time to break down the pinion...the Milwaukie electric impact easily takes the pinion nut off.

I'll start with .094 for the pinion shim...

...and install the Toyota factory collar with .042" worth of shims (took me 5 times to get this one right).

094 is way too shallow...high on the face and too close to the heel.


Changed the shim to .101 and still shallow.


.106 looks very good.


Skipped a few steps here but lots of red LockTight and 200 ft/lbs or so on the pinion nut.

Done :)