LX570 rear 3rd gets ARB RD152
(48 good size pics loading)
MAY 11 2012

The LX570 race team story (click on the slide show)



Joe Bacal, primary driver for the Lexus team, brought over the very heavy rear 3rd and one RD152 ARB locker.

New carrier bearings will be pressed on even though the "old" ones are said to have only 200 miles on them.

Beefy towers, beefy bearing caps, beefy carrier bearings, and an overbuilt 4 pinion open case make for a very robust 9.5" 3rd.

Backlash is characterized and recorded on every second or third tooth. Backlash averaged .0065".

Not needed for this install but I'm in the habit of dimpling both adjuster wheels in the straight-up, 12 o'clock position as a reference during re-assembly. There's white paint on the left side of the bearing cap so no dimples needed there either.

Always a good idea to paint the factory pattern before swapping in an ARB. Drive side shown here.

Here's the coast.

Drive side on the pinion.

Drive side....reverse painted.

coast...reverse painted.

My favorite spanner tool.

Sometimes, I use a tiny cutting wheel on the dremel tool to mark the bolt and bearing caps so I can be sure I get them AT LEAST this tight upon re-assembly.

Bearing caps are removed and the heavy case is transferred to the work table.

Pinion pre-load measured at 9 in/lb starting torque. This is factory after 200 miles at best.

Rolling torque measured at a much lower 2 in/lb. Starting versus rolling can vary quite a bit.

This wrench has been ground down flat to get maximum bite on the limited surface area of the very tight flange bolts.

The high strength OEM loctite makes it a challenge to break loose some of these flange bolts.

All are removed with no damage.

The ring gear is tapped loose.


Before the ring gear is mounted to the ARB it's always a good idea to run a file over both surfaces to remove any high spots.

I could have seated the ring gear with the press but I opted to use the bolts to pull the ring on. No real force was applied to the ratchet. Just the way I am holding the ratchet in the pic was enough to pull it on steadily.

Threads were cleaned 100% and red Loctite applied.

92 ft/lb verified on all 12.

The new KOYO bearings pressed on very tight.

Per the ARB instructions, a hole is drilled from the outside in....

....then another is drilled and tapped for 1/8" NPT.

This keeps the copper tubing on the ring gear side and snakes the copper inside the 3rd and back out to the brass bulkhead fitting. It can be a small challenge to route it in a clean manner.


No way around it...forming it is a "bear".

Finally, after playing with it for about an hour, it is done.

It's not obvious in the pic but a thick grease has been applied to thread surfaces.

Bolts are threaded in about 3 turns each and the bearing caps are then tapped down fully. The way it seats...the noise it makes...and the way it feels tell me if the threads are 100% aligned.

X-rings are lubed up and put in place.


Bearing caps are then tightened to 85 ft/lb and the adjuster wheels still turn smoothly with very little real resistance...the ultimate verification that the threads are lined up :)

Backlash is dialed in. Even though I do rap on the sides of the towers while turning the pinion to equalize the bearing tension on both sides I still make my last "turn the adjuster wheel in 1 notch" adjustment on the ring gear side itself....a good practice for all gear installs.

Even with well greased threads, it took 100ft/lbs before the wheel started to move. 100 is a good all-around pre-load to use.

Retaining clip is snapped in place.

Blue Loctite and 10 ft/lb on both lock-tab bolts.

PASS the ARB air leak test.

A final paint check to make sure it's the same as the initial paint and it is.


Pinion driveside.



Ready for pick up :)