Differential - Carrier Bearing Preload ?

Spanky Pete · 08-26-09, 05:49 PM

I am setting up a rear differential. How do I measure carrier bearing preload? I know how to adjust it, but not sure how to get a preload torque value.

I noticed on Zuk's web pages he has listed CBPL of 130 or 150 ft lb for the landcruiser diffs. He has the value listed at the very end of a project, but I don't see anywhere where he describes how her measures it. He seams to describe everything else in great detail

gear install
Toyota gear install

Spanky Pete · 08-26-09, 06:30 PM

Ok I answered it myself. I found this picture on a four runner project write up on ZUK's site

gear install

lehiguy · 08-27-09, 07:54 AM

I do it by feel. That might sound crazy to some, but that's how I do everything except rod, crank and head bolts.

land crusher · 08-27-09, 09:55 AM

As an aside, I find that diff info is one area where mud is lacking. People are afraid of them for some reason. Diff questions are often answered with something to the tune of "take it to a shop or the sky will fall."

Anyhow, I'd encourage those of us who do work on our differentials to post about it so we can fill this hole in an otherwise great resource. I was going to do a writeup of my ARB install, but alas, I got lazy when confronted with the prospect of having to change gloves or wash my hands every time I needed to pick up the camera (which would have been alot). Yes, lame excuse. I think I need to get a cheepo digital camera solely for greasy photo shoots.

GLTHFJ60 · 08-27-09, 10:56 AM

Quote:

Originally Posted by land crusher

As an aside, I find that diff info is one area where mud is lacking. People are afraid of them for some reason. Diff questions are often answered with something to the tune of "take it to a shop or the sky will fall."

Anyhow, I'd encourage those of us who do work on our differentials to post about it so we can fill this hole in an otherwise great resource. I was going to do a writeup of my ARB install, but alas, I got lazy when confronted with the prospect of having to change gloves or wash my hands every time I needed to pick up the camera (which would have been alot). Yes, lame excuse. I think I need to get a cheepo digital camera solely for greast photo shoots.

I completely agree with you! I'm tempted to gear down some more and do a full blown write-up.

Spanky, document your process!!

Spike Strip · 08-27-09, 11:36 AM

Quote:

Originally Posted by land crusher

As an aside, I find that diff info is one area where mud is lacking. People are afraid of them for some reason. Diff questions are often answered with something to the tune of "take it to a shop or the sky will fall."

I think that's an astute observation... I tried doing my 3rds, with ARB install, but got scarred away after buggering the pinion preload, so I ended up sending sent them to ZUK. But had there been more info here on MUD, who knows...

lehiguy · 08-27-09, 09:22 PM

Quote:

Originally Posted by land crusher

As an aside, I find that diff info is one area where mud is lacking. People are afraid of them for some reason. Diff questions are often answered with something to the tune of "take it to a shop or the sky will fall."

Anyhow, I'd encourage those of us who do work on our differentials to post about it so we can fill this hole in an otherwise great resource. I was going to do a writeup of my ARB install, but alas, I got lazy when confronted with the prospect of having to change gloves or wash my hands every time I needed to pick up the camera (which would have been alot). Yes, lame excuse. I think I need to get a cheepo digital camera solely for greasy photo shoots.

Too True! My first gear setup went so smoothly, I felt like an idiot for having paid people for years to do something so simple.

GLTHFJ60 · 09-01-09, 01:12 PM

So where's the writeup, Spanky?

Kynot62 · 09-02-09, 03:50 PM

To answer your original question, the pre load is set with a dial indicator and how far you tighten things down. The FSM is very clear in how it's done. There is no torque wrench setting involved.

I have gone through my diffs twice now. The first time to change the gears and the second time to install my ARB's. Had to do it twice because I couldn't afford to do it all at once.

Both times I followed the FSM to the letter and had no problem whatsoever. The only part not covered very well is how to read the paint marks during the gear set up and in that area I just read through the install info that came with my Yukon gears.

The only trick I came up with during the gear install was to have an outer bearing (flange side) that was loosened up so I didn't have to keep pounding out the pinion to set the depth of it. This loose bearing is only used for set up not the final install. Not needed if you are just installing ARB's as you don't need to change the pinion depth.

Trust the FSM and have at it. It's not that hard

Tony

chesshircat · 09-02-09, 05:20 PM

Don't be scared!!! I did it for the first time last summer on my 89 mini with some help from mud. I had a thread going i'm not smart enough to link you to it but if you search my screen name you'll find it. You need a dial indicator to set back lash and get the carrier preload to zero, you'll need a inch pound torque wrench to set preload, a torque wrench to torque the bearing caps, but other than that its pretty straight forward. the hardest part for me was getting the crush sleeve crushed right, it took me 2 tries. the FSM will walk you through all the specs. just check it, recheck it and check it again

Pin_Head · 11-07-09, 12:14 AM

The Toyota factory method for carrier bearing preload is measured at the pinion nut, just like the pinion preload. It is 20 inch pounds higher than the pinion preload (which is about 10-12 inch pounds) for new bearings. First you measure the pinion preload and write it down. After you install the carrier, you measure it again and set the carrier preload so the total is 20 inch pounds + the carrier preload or approximately 30 inch pounds total. The spec is lower for used bearings. This is explained well in the FSM.

Spanky Pete · 11-08-09, 08:21 PM

Sorry I dropped the ball on the write up. I got busy and just did it without taking time to take pictures or detailed notes.

Really not that difficult of a job. I did run into a little bit of a problem because the used gears I picked up from tonyota included a pinion with a spacer machined in, so my solid spacer would not work with that particular pinion, and I had to stack a bunch of shims on there, but in the end, I got the pinion pre-load adjusted to specs. No problems with the rear yet.

I ended up measuring CBPL at the pinion nut just as pinhead described, after I took another look at the FSM.

It can be difficult to remove a new inner pinion bearing without damaging it if you don't get the pinion depth right with your factory shim under the bearing. Shims under the race were easier to change out in setting pinion depth, but adjusting pinion depth here, changes your pinion bearing preload, so lots of shimming adjustments.

How is that for a write up...

Spook50 · 11-09-09, 04:30 PM

Quote:

Originally Posted by land crusher

As an aside, I find that diff info is one area where mud is lacking. People are afraid of them for some reason. Diff questions are often answered with something to the tune of "take it to a shop or the sky will fall."

Anyhow, I'd encourage those of us who do work on our differentials to post about it so we can fill this hole in an otherwise great resource. I was going to do a writeup of my ARB install, but alas, I got lazy when confronted with the prospect of having to change gloves or wash my hands every time I needed to pick up the camera (which would have been alot). Yes, lame excuse. I think I need to get a cheepo digital camera solely for greasy photo shoots.

I agree as well. I plan to do my own diff rebuilds when SOA time comes to install new gearsets and (most likely) Auburns. Would be nice to see some more info on this here.