DIY 4.3 Re-Gear (2 Viewers)

[bloc]

After inspecting the 3rd member all looked good with exception to one of the Diff Case Side Bearings.
The splines inside all look good , no visible wear. Just some heavy scarring on one side of the bearing.
Does this look like unsual wear and something that should be addressed before install? Or could this simply be damage that incurred during the removal by the "ebay pick n pull" seller. Hard to imagine they could scar and damage the bearing when removing the axle shafts.

View attachment 3543268

View attachment 3543269

Junk yards suck at this.

The damaged part isn't the bearing itself, it's the diff carrier extension that goes through the side bearing. To me it looks like they didn't have the axle all the way out then tried to pull the diff.. my question is how they pulled hard enough to make that mark? Are there pry marks on the mounting flange?

Other possibilities are somehow having the axle inserted then trying to pry sideways for some reason?

There shouldn't be any contact there during normal use.. that isn't wear. Possibly from a really really bad accident involving the rear axle..

I'm on the OCD end of things and would probably tear it down (after marking the bearing position so I could get it back to factory lash, and on this model I'd leave the ring gear in place) to make sure the thrust bearings in the spiders are in good shape, and consider filing down the raised parts of the damage to make sure there's no interference with the axle splines.

 

[TLC2013]

Junk yards suck at this.

The damaged part isn't the bearing itself, it's the diff carrier extension that goes through the side bearing. To me it looks like they didn't have the axle all the way out then tried to pull the diff.. my question is how they pulled hard enough to make that mark? Are there pry marks on the mounting flange?

Other possibilities are somehow having the axle inserted then trying to pry sideways for some reason?

There shouldn't be any contact there during normal use.. that isn't wear. Possibly from a really really bad accident involving the rear axle..

I'm on the OCD end of things and would probably tear it down (after marking the bearing position so I could get it back to factory lash, and on this model I'd leave the ring gear in place) to make sure the thrust bearings in the spiders are in good shape, and consider filing down the raised parts of the damage to make sure there's no interference with the axle splines.

Thank you for your two cents. I am learning here as I go, so it's much appreciated. That OCD is strong with me as well so seeing this really made my day lol.
When i bought the tundra front diff and 100 series rear I made sure the vehicles were totaled in an accident that didn't impact the area of the drive train i was after. The trundra was rear ended and the 100 series was in a frontal collision. Nevertheless i still couldn't avoid the headaches of buying used from a salvaged yard.

The damage is only to that area. Sure looks like a bad pull job by the junk yard..get what you pay for. Here are a few more photos

 

[bloc]

Thank you for your two cents. I am learning here as I go, so it's much appreciated. That OCD is strong with me as well so seeing this really made my day lol.
When i bought the tundra front diff and 100 series rear I made sure the vehicles were totaled in an accident that didn't impact the area of the drive train i was after. The trundra was rear ended and the 100 series was in a frontal collision. Nevertheless i still couldn't avoid the headaches of buying used from a salvaged yard.

The damage is only to that area. Sure looks like a bad pull job by the junk yard..get what you pay for. Here are a few more photos

View attachment 3543590

View attachment 3543591

View attachment 3543593

Is there also damage 180 degrees from the part in the pictures? Like if they had the axle shaft inserted partway then tried to bend it?

More info on my imaginary plan to tear it down.. As long as you put the tensioners on the sides with all the holes back into their exact position, you can remove the diff carrier and ring gear, then put it back into place without impacting the gear setup. You'd be wise to get a dial indicator to double-check your lash, and probably need to fab up something to rotate those bearing preload adjusters with a fair amount of torque.

But, as I remember it the carrier can be removed and cracked in half to inspect the innards, without removing the ring gear (and dealing with the red loctite on the bolts.) Verifying the condition of the carrier bearings and the thrust portions of the spiders would be good enough for me.

 

[TLC2013]

Is there also damage 180 degrees from the part in the pictures? Like if they had the axle shaft inserted partway then tried to bend it?

More info on my imaginary plan to tear it down.. As long as you put the tensioners on the sides with all the holes back into their exact position, you can remove the diff carrier and ring gear, then put it back into place without impacting the gear setup. You'd be wise to get a dial indicator to double-check your lash, and probably need to fab up something to rotate those bearing preload adjusters with a fair amount of torque.

But, as I remember it the carrier can be removed and cracked in half to inspect the innards, without removing the ring gear (and dealing with the red loctite on the bolts.) Verifying the condition of the carrier bearings and the thrust portions of the spiders would be good enough for me.

There are some marks 180 degrees, on the opposite side. Much smaller ones but visible non the less as seen in the photos. More reason to tear it down, replace the guts and add a locker.

 

[highfructose]

There are some marks 180 degrees, on the opposite side. Much smaller ones but visible non the less as seen in the photos. More reason to tear it down, replace the guts and add a locker.

View attachment 3543610

If you’re going to the expense/time of swapping diffs, I’d add lockers and swap out all bearings and seals (that’s what I’m planning to do).

 

[bloc]

There are some marks 180 degrees, on the opposite side. Much smaller ones but visible non the less as seen in the photos. More reason to tear it down, replace the guts and add a locker.

View attachment 3543610

Just be aware if you do the pinion bearings too it adds a ton of work, and really, ambiguity, as you have to learn to interpret the gear pattern. Carrier bearings alone and adding the locker aren’t very difficult jobs though.

 

[TLC2013]

@bloc @highfructose appreciate your insight. My initial idea was do a simple swap of the 3rd member to get the OEM 4.30 gearing upgrade. Not happy seeing this type of wear/damage.

Plan “B” will be to file/smooth out the marks and install as is to see how it performs, hopefully a non issue. This will give me time to Build out my original 200 rear diff and swap back in locker and all.

 

[ROMR NTX]

Found an extremely low mileage Tundra 4.3 front locally for a good price so I jumped on it.

My plan was to get a used Tundra front then get a new rear from Japan with the e-locker

I've watched many threads on videos on rebuilding the diffs and know that I want no part of it. Swapping in complete 3rds is well within my capability.

Funds for a NEW rear will have to wait a while though. I do see some LX470 4.3s for sale, for a few hundred bucks. Claimed mileages are under 200k.

I know it's kind of a loaded question, but how risky is it to drop an old one like that in without rebuilding? Plan would be for it to be relatively temporary, year max.

 

[bloc]

Found an extremely low mileage Tundra 4.3 front locally for a good price so I jumped on it.

My plan was to get a used Tundra front then get a new rear from Japan with the e-locker

I've watched many threads on videos on rebuilding the diffs and know that I want no part of it. Swapping in complete 3rds is well within my capability.

Funds for a NEW rear will have to wait a while though. I do see some LX470 4.3s for sale, for a few hundred bucks. Claimed mileages are under 200k.

I know it's kind of a loaded question, but how risky is it to drop an old one like that in without rebuilding? Plan would be for it to be relatively temporary, year max.

A year max? Zero risk, as long as it's a clean part upon inspection.

Toyota pretty much makes the best non-HD roadgoing gear systems money can buy.. that would give me a ton of confidence in this context.

 

[ROMR NTX]

A year max? Zero risk, as long as it's a clean part upon inspection.

Toyota pretty much makes the best non-HD roadgoing gear systems money can buy.. that would give me a ton of confidence in this context.

Yeah the "upon inspection" is the worry I guess. Not that sure what to look for other than everything being relatively tight when I get it. Aside from tools and expertise, I just don't have time these days to piddle with stuff like this. Gimme clean parts ready to go and I'll find the motivation

But if it's a decent part seems pretty low risk. I'd be able sell it later and easily recoup a ton of the money.

 

[bloc]

Yeah the "upon inspection" is the worry I guess. Not that sure what to look for other than everything being relatively tight when I get it. Aside from tools and expertise, I just don't have time these days to piddle with stuff like this. Gimme clean parts ready to go and I'll find the motivation

But if it's a decent part seems pretty low risk. I'd be able sell it later and easily recoup a ton of the money.

You could always try to find a chunk from a forum rig that is getting parted out or something. I’d trust this a bit more than a random junk yard diff, if not from the city I live where I can get a feel for the part in person.

 

[highfructose]

I've watched many threads on videos on rebuilding the diffs and know that I want no part of it.

I’ve been slowly completing a locker install as a novice and have found that if you singularly focus on one step at a time, which is easy since it all happens on a bench while your vehicle is still useable and there are people with experience you can query in this forum, no individual step in the process is particularly difficult…so far anyway.

I am currently planning on putting a locker in the front too…supposedly the diff install for the rear is 3 hrs, front is 5…I assume if I’m going to the trouble of 8 shop hours (probably 16-24 me hours), I might as well triple lock it.

 

[ROMR NTX]

You could always try to find a chunk from a forum rig that is getting parted out or something. I’d trust this a bit more than a random junk yard diff, if not from the city I live where I can get a feel for the part in person.

Besides FB marketplace and eBay where are y'all looking? Only other local way I have experience with is the pick n pull

 

[bloc]

Besides FB marketplace and eBay where are y'all looking? Only other local way I have experience with is the pick n pull

Car-part.com is an online index of parts at yards all over the country. You can filter by part, ratio, year, distance from you, etc. Depending on your region there may be a few near you that you can go look at, sometimes with the vehicle it did or will come out of.

 

[ROMR NTX]

Car-part.com is an online index of parts at yards all over the country. You can filter by part, ratio, year, distance from you, etc. Depending on your region there may be a few near you that you can go look at, sometimes with the vehicle it did or will come out of.

Maybe I'm doing something wrong but every time I go to car-part I find nothing. No matter what make/model/year I'm looking for

Always this screen

 

[TLC2013]

Maybe I'm doing something wrong but every time I go to car-part I find nothing. No matter what make/model/year I'm looking for

Always this screen

View attachment 3550173

I was having the same issue with car-part. Was about to give up when i finally had sucess using a part description like axle assembly or something along those lines.

I found one on ebay but ended up returning it due to some unusual wear / damage to the carrier. Probably would have been a non issue but after seeing images of the vehicle it was pulled from i got cold feet.
After factoring in the cost of rebuilding the used diff with OEM parts it wouldn't have cost much more to get a brand new one especially if you can wait for the 15%-25% off parts sales that pop up every so often. I am going to either buy a new one or have one built by Cruiser Outfitters.
It's amazing how cheap and easy it is to source a good order tundra front for only a couple hundred bucks and the rear can cost 10x as much lol. All in all its still an amazingly affordable way to regear both axles and add a locker.

 

[TLC2013]

This will get you there:

 

[ROMR NTX]

Jackpot!

Strange though. From reading this thread only 02 and later LXs have the 4.3 ratio

When I search car part though I see lots of 00-01 Cruisers and LXs listed as having 4.3

 

[highfructose]

Jackpot!

Strange though. From reading this thread only 02 and later LXs have the 4.3 ratio

When I search car part though I see lots of 00-01 Cruisers and LXs listed as having 4.3

I think
1998-2002 have the 4.30
2003-2007 have the 4.10

1998-1999 CAN have the rear locker in lc’s…I’m not sure which lx470’s from 1998 and 1999 have the limited slip…could be all.

 

[skrypj]

So, would the 3rd member from a 4.7 or 4.6L Tundra be a drop in since they used the 9.5" axle? With the 2016+ 8 speed trucks having a factory 3.31 ratio, the 3.91's from the Tundra 4.6L would be pretty mint with a 35" tire, or even a 37. Even with a 37", they would still be slightly shorter overall than the stock 3.31/32" tire combo.

1st gear would be shorter than the 6 speed trucks with 4.88's, but 8th would still be decently tall for the freeway. I figure it would be at 2000 rpm running at 75mph with a 315/70R17