Thomas from Picayune, Mississippi, has been pushing his 42" tires with 410 gears. He says it was no fun ;) .....this is on a carbed 5 speed truck. The plan is to install high quality Precision 571 gears into a regular "4 cyl 3rd" to get his over-all gearing back in line.

Making a few assumptions.....let's say that off the showroom floor it had the 410 gears and 29" tires....4.10/29 = X/42 and solving for X means that with the 42" tires that the gearing has to be 5.93 to maintain perfect accuracy of the speedometer so 571 is pretty close.


Update 12-24-2016.......I reached out to Tommy on Facebook and was wondering if he had the same Toyota and how the 571 is holding up and here's his reply....

"I sold it years ago but I never had any issues for the 3 years I ran it hard. I broke an axle or two when I went to a 4.3 v6 but never the diff."

Thomas couldn't find anyone local that was capable of doing a decent gear install so he found me in cyber space. New bearings and a solid collar will enhance this install. These 571 gears will last a long time inspite of 42" meats.

Step one is to tear down and clean the open 3rd...

Taking the old carrier bearings off is 'cake' with the right puller. I can't say enough about this OTC-4520 puller. These pullers are on Ebay.com.
Notice that Precision does a pattern check with yellow paint. This is a nice QC step and I commend them for it. They are the only supplier of Toyota gears that does that ;)

The not so glorious job of cleaning everything is done with the high speed wire wheel and lotsa starting fluid.

Even the threaded ring gear holes get cleaned. The ring was briefly filed to insure a flat surface.

Here, I'm using red Loctite on the clean threads and 75 ft/lbs torque.

The pinion is installed first....a .093" pinion depth shim will be the first try and .066" for the solid collar shim. I had to break it down only once and change the collar shim to .062" and then the pinion pre-load was at a nice 9 in/lbs.

Note to self....keep gloves in the clear while tapping the bearings down..... now I get to use the puller again :)

Some shops might say this is good enough. Wash the paint off and button it up. Customer will never know the difference. That's not the way I operate. This drive side pattern is way deep.

The coast confirms that...

I made a big jump to 080 and still very deep.

It's deep.

Went down to 074 and getting close....still deep though.

Coast side still agrees on being deep....

Beautiful.....

Super NICE.

That great pattern means nothing if the carrier bearing pre-load is set low. Sometimes, I use the torque wrench to make sure it's at least 100 ft/lbs or so. I also use the hammer to rap on the bearing caps to equalize the bearing tension.

The new factory seal has a liberal coating of gear oil to prevent a dry start-up.

Bullseye really is a cool bangal cat.

A nice coat of black paint....a new flange....and a ZUK tag.

Ready for the trip back to Mississippi. This particular box has about 4 or 5 layers of cardboard inside. No way this 3rd will break thru.