Jon from Montana gets 529 Ninja Gears and a Harrop A9334 elocker
(56 BIG pics loading)
FEB 18 2020

Jon's Toyota pickup already had 529 gears when he bought it but they also made a howling noise on decel.

He removed the rear 3rd and inspected it closer and decided that the gears and bearings were all toast
so Jon sent the stripped down V6 3rd to me in a somewhat unique "carrier".....but it got the job done.

Jon also sent the gears and bearing kit. Those are "Ninja Gears" but closer inspection seems
to show they are just normal Yukon Gears with the ring gear stamped with
"TV6/529/29-37x7 H18 231"


The stripped down V6 3rd was cleaned up and a satin black coating applied(mostly for cosmetics)
The Harrop A9334 elocker will see the Ninja Gear bolted to it soon.

Yukon bearings and NINJA to be mounted.

70 ft/lb and red loctite #263. 263 has the best "break-away torque" spec of the high strength loctites.
........which should mean that the ring gear bolts are less likely to ever loosen up on their own.

Ring and carrier bearings on. This piece is complete.

These are the NINJA markings.

Inner pinion race goes in now....

Tap tap tap and it's down all the way....100% verified that it is seated down.

The small outer race is next.

100% seated chisels are used....

Now the pinion gets attention....which pinion shim to try first?.....Let's try .0745"

Mount the pinion in the diff carrier and then install the Harrop assembly.....

Drive....0745".....very shallow


Even the comet tail says shallow...deep in the pinion is shallow on the ring(equal but opposite).


Now is a convenient time to drill the 29/64" hole for the rubber grommet.


Let's add .020" to the .0745" shim for a total of .0945"

100's and 100's of pinions have seen this bearing separator(purchased back in 2007).

Now to mount the pinion with the new .0945" shim again

drive...0945".....might be a tad shallow.

coast....looks ideal.

comet tail is in a good spot....not hard into the root and not too close to the center.


I did want to reset the pinion shim a little deeper so added .002" shimming.
This drive side looks good.

But this coast side looks too hard into the root.

and the comet tail is flaring too far to the outside.

too far to the outside.....

yep.....time to reset the shim back to .0945" as that is the best for all paints concerned.


And with the pinion shim back to the 0945 number, now the solid collar goes in.
On the 3rd shim value, solid collar was set perfect.

The Yukon 29 spline seals appear to be made from a high quality rubber compound...similar to the factory material.

Recessed about 1.3mm


New 29 spline flange is going on. Anti-seize on the threads.


A nice 10 inch/pounds pinion preload.

DING!!! on the new nut.

I usually notice this before tapping down the carrier bearings but this one almost sneaked by me.
If the race says LM104912 then this race is too small by .0027"
Easily verified online at
LM104912....... OD=82.931mm

This is the ONLY carrier bearing that the Toyota factory uses for this carrier application.
TR100802-2........ OD=83mm exact

It appears that numerous bearing kits think it is an acceptable substitute for the TR100802-2 it is not for me.....
....and neither was it for Jon.

Now getting the carrier bearing off can get interesting sometimes.....
Shown here, there is not enough real estate for the fingers to grab onto.

I have my own technique for bearings that do not cooperate.

Done :)

A new set of TR100802 bearings will be tapped on.

Now it's good to go.

Pinion end is complete. Now to measure/set the backlash and make sure the carrier bearing preload is set solid.

A last pattern check with .0945" shim and looks just like expected.


Now to check the resistance of the Harrop magnetic coil and measuring 3.8 ohms.

12volt check of the actual engagement and all is good.

With backlash and bearing preload set, now the tabs are tightened to 10 foot/pounds with blue loctite.


Notes of the actual install.

The NINJA gear had enough backlash variations that I thought I would characterize it for all 37 teeth.