DIY 4.3 Re-Gear (1 Viewer)

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Does anyone know whether the AHC system has to be depressurized in order to get the cv’s pulled out far enough to swap the front third member?

Like in order to give the cv enough space to get out, do you have to disassemble the front strut?
I can say that I did not. You will need to unbolt the knuckle under the ball joint though separating it from the lower control arm. I needed a helper to pull the cv axle with wheel assembly while I pried/ motivated with a hammer to overcome the spring snap ring. After that there is no good place to put the cv axle so it will be in the way slightly while dropping the diff
 
I was also able to keep the outer end of the CV in place, only removing the inner CV from the diff to drop the clamshell, but for whatever reason I couldn't get the inner CV to engage with it still attached to the knuckle, so I ended up fully removing both of them to get the inners back in. Probably just operator error on my part, since other people manage to get it in while attached. The specialty tools made for removing the inner CV work great.
 
Finally getting around to checking my locker with the rig off the ground.

So if I switch the locker on and the switch lights up, but when I turn the rear driver tire the passenger spins in the opposite direction, I assume it’s not locked?
 
Finally getting around to checking my locker with the rig off the ground.

So if I switch the locker on and the switch lights up, but when I turn the rear driver tire the passenger spins in the opposite direction, I assume it’s not locked?

Some lockers do need a certain amount of torque on them to engage.. not sure if what you have is one of those.
 
Does removal of the front third in an lx570 require removal of the strut assembly (and thus cracking of the ahc system) in order to pull the cv’s out of the way?

Or can you get the cv’s out of the way and pull the third without messing w the ahc system?
 
Does removal of the front third in an lx570 require removal of the strut assembly (and thus cracking of the ahc system) in order to pull the cv’s out of the way?

Or can you get the cv’s out of the way and pull the third without messing w the ahc system?

You do not need to open the AHC.
 
Does removal of the front third in an lx570 require removal of the strut assembly (and thus cracking of the ahc system) in order to pull the cv’s out of the way?

Or can you get the cv’s out of the way and pull the third without messing w the ahc system?
No you do not need to open the AHC. The real question is if you want to remove the CV axle from the wheel hub or not. It can be done either way
 
No you do not need to open the AHC. The real question is if you want to remove the CV axle from the wheel hub or not. It can be done either way

Fortunately neither. Can remove the ball joint bracket at the LCA and that create enough movement and flexibility to pull the CV with the upright together.
 
How might one identify whether the tundra third member they’ve pulled will fit the land cruiser? Is there a serial on the third member somewhere?
 
Fortunately neither. Can remove the ball joint bracket at the LCA and that create enough movement and flexibility to pull the CV with the upright together.
That's what I was trying to say but didn't articulate it well.

How might one identify whether the tundra third member they’ve pulled will fit the land cruiser? Is there a serial on the third member somewhere?
Most yards separate the front diffs by gear ratio and engine size. You'll want a 4.30 from a 5.7. As far as actual markings I am unsure, I didn't check mine.
 
That's what I was trying to say but didn't articulate it well.


Most yards separate the front diffs by gear ratio and engine size. You'll want a 4.30 from a 5.7. As far as actual markings I am unsure, I didn't check mine.
From Teckis's thread, it needs to be a Tundra with a tow package. I suspect most Tundras came with the tow package.
 
That's what I was trying to say but didn't articulate it well.


Most yards separate the front diffs by gear ratio and engine size. You'll want a 4.30 from a 5.7. As far as actual markings I am unsure, I didn't check mine.
Are the 4.10 front diffs different than the 4.30’s?
 
Are the 4.10 front diffs different than the 4.30’s?

Everything is in the very first post of this thread. 4.3s are what you want. 3.9s are stock for us 6-speeders, and 4.1 is not enough to warrant a swap IMO.

For more detail, this post
Rear Diff
- 4.3 carrier from 98-02 LC or LX. This ratio came from the 4-speed cruisers of the day (03+ got 5-speeds)
- There are factory locked ones available. Comments suggest this could be retrofitted for air actuation. For LX models only that won't have sway bar interference against the actuator.
- Carrier is directly drop into the 200-series
- Note that the 100-series uses a smaller diameter input flange and snout on the pinion shaft. If you're just looking to source the ring and pinion with full size snout, and will rebuild from your current diff, @bloc was able to sleuth a new OEM R&P 4.3 parts kit ( 41201-80493 )
- I sourced mine for $120; $200 shipped

Front Diff
- 4.3 carrier from Tundra or Sequoia. Probably 08-20?*. 4.3s only came on these models with the optional tow package. Look for door sticker axle code B02A. Parts resellers should have the associated VIN which you can check on Toyota website to confirm tow package in options list.
*I don't know that there were absolutely no changes through 2020 that affect fitment on the 200-series. Mine is from a Tundra 2012 that fit fine.
- Fitting a locker to a front clamshell carrier is supposedly no joke with need for special measuring tools for lash. Fortunately if not looking for a locked front axle, it otherwise drops in after changing out the peripheral ADD actuator
- I sourced mine for $175 shipped
 
Everything is in the very first post of this thread. 4.3s are what you want. 3.9s are stock for us 6-speeders, and 4.1 is not enough to warrant a swap IMO.

For more detail, this post
Yeah I’ve already got the 4.10 land cruiser rear and tundra front. I did some research a year or so ago that indicated the tundra 4.10 front should be identical to the 4.30…it’s been a while though so my memory is murky on it.

I think I need to pull the tundra front 3rd member out and do some measurements compare to the one currently in my Lexus.

As to the utility of a 4.10…I think the front and rear cost me around 450 dollars total…I don’t plan on running larger than 33’s but my rig is somewhat heavy and I do plan on putting a limited slip in the rear.

4.10’s due to price and my vehicle pramaters seems to make more sense than 4.30’s
 
I believe Toyota is more likely to use a printed part number or paint marks for the whole pre-setup assembly, as they’d share part numbers for the case parts independent of the gears installed within. These superficial marks could be long gone on a used junk yard diff.

If you have access to the body tag from the donor vehicle you can check the diff ratio indicators.. but that may not be possible to track down.

Someone setting up gears in these front clamshells inserts a probe type dial indicator into the diff drain, which is made large just for this purpose. If you aren’t sure of the exact ratio you can remove the plug then mark a ring gear tooth and count how many there are in a full revolution. Alternately just measure the rotations but I found this difficult when differentiating between similar ratios like 4.1 and 4.3. Number of gear teeth is definitive.
 
I believe Toyota is more likely to use a printed part number or paint marks for the whole pre-setup assembly, as they’d share part numbers for the case parts independent of the gears installed within. These superficial marks could be long gone on a used junk yard diff.

If you have access to the body tag from the donor vehicle you can check the diff ratio indicators.. but that may not be possible to track down.

Someone setting up gears in these front clamshells inserts a probe type dial indicator into the diff drain, which is made large just for this purpose. If you aren’t sure of the exact ratio you can remove the plug then mark a ring gear tooth and count how many there are in a full revolution. Alternately just measure the rotations but I found this difficult when differentiating between similar ratios like 4.1 and 4.3. Number of gear teeth is definitive.
If one were swapping the entire assembly, not just the carrier, how might one check to see whether more than just the 4.30 assembly is plug and play?
 
If one were swapping the entire assembly, not just the carrier, how might one check to see whether more than just the 4.30 assembly is plug and play?
I don’t understand your question. Teckis showed what needed to be changed on the front diff to bolt in, as long as the ratios are correct drop both in and hit the road.
 
I don’t understand your question. Teckis showed what needed to be changed on the front diff to bolt in, as long as the ratios are correct drop both in and hit the road.
I have a tundra front diff from around 2012 with 4.10’s…wondering how to tell whether, like the tundra front diff with 4.30’s, the tundra front diff with 4.10’s will drop right into a land cruiser
 
I have a tundra front diff from around 2012 with 4.10’s…wondering how to tell whether, like the tundra front diff with 4.30’s, the tundra front diff with 4.10’s will drop right into a land cruiser
You might want to go back and re-read this thread and look at some of the pictures. Once you change the 'tail' of the diff with the one you pull off of your cruiser diff as illustrated by Teckis, it will fit in your cruiser. If you're asking if the whole 4.10 clamshell/front diff is the same size as the 4.30 the answer should be yes, the only difference should be the gear ratio.
 

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