Using 1999 diffs in a 2000+ LC/LX?

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Nov 13, 2006
Sunnyvale, CA

My 1999 built rig rolled recently and got totalled. I bought it back from my insurance company and am now trying to figure out what my next rig should be (that's a whole different question and will post some of the other questions after having read the forum posts some more). One question I have is on the diffs. I had regeared my LC to 4.88s and had the factory e-locker in the back and ARB locker in the front. If I get a 2000+ LC, will I be able to take the current diffs and replace them in the new LC? Maybe the whole diff carrier and axle combo. I know the e-locker option was removed in the 2000+ years but does the e-locker harness still exist? I can take out the ECU and whatever else is needed from my current truck. Are there any mechanical challenges? Will it interfere with A-Trac or VSC? I think they use the brakes and don't do anything with the diffs but not too sure.

How about the LX? Does the AHC have different suspension mount points etc (on the rear axle) to make the axle/diff swap in-feasible?

Basically I'm trying to avoid the cost of new lockers and re-gearing if possible.
I'm a bit far from that yet :) Gotta get a new rig first. But you're first in queue if that happens. Am I to take it that you think its possible?
You should be fine on the front end, but the rear will be a challenge. There's slight grinding you have ot do on the axle housing to clear the e-locker (see the 80 series section for retrofitting e-lockers in a nonlocked truck, it's the same for the rear of the 100).

As for the electronics, that's another crap shoot. Even with the rear diff ECU, none of the wiring may be there. I don't know if the e-locker continued to be available outside of the US after '99. If it was, it's possible that the wiring may still be there. Either way, you should be fine with the ATRAC and VSC. You'd only be locked at low speeds and there's several people that have ARBs and ATRAC.
What if I replace the rear axle housing itself from my current LC? Would that be a possibility? I guess I need to take a hard look under a 2000+ model. I wonder if anyone with a 2000+ has noticed whether it has the diff switch connector in the switch console to the left of the steering column. Its a 4 pin connector - I'll try and post a picture soon.
I'd do like Cory says and just stick the elocker diff in the new housing. Don't worry about the wiring for now. Pull the wiring from the diff to the inner quarter panel. After that you can go custom. Just like the people using 80 series diffs in other vehicles. There is a harness you can buy for a little over 100 dollars that goes all the way to the diff. But I think you'd be better off taking that part from your old truck. You want to keep the ATRAC and VSC. As for the switching, do the upgrade and run an 80 series F/R elocker switch for both the rear and front ARB.
Just so I understand - what is in the axle housing that is used in the ATrac / VSC? My impression was that both these systems use the ABS system - but I could be mistaken. I know for example that in the new BMW M5, the ABS system as well as an electronically controlled limited slip diff is used for their version of stability control. Or is there something mechanically different in the 2000+ axle housing vs the 1999 axle housing.

Again I haven't had the opportunity to look under a 2000+ LC so am trying to lean on other's experience. How different is the 2000+ LX axle housing vs an LC of the same year. Ie if something is possible with an LC then would it mean its also possible with an LX?
I see what you're saying. I'm a little apprehensive about opening the diff and replacing it into the new housing - is that a very skilled job? I know I wouldn't attempt to regear a diff for sure, but I'm quite comfortable opening up the axles - I've completely redone both front and rear on my 99. Not quite sure where the diff replacement falls in the skill spectrum. Which is why I was thinking of replacing the whole axle assembly. But what you suggest might be something doable. I did put in a F+R oem locker switch in my 99 for running the front arbs as well, and can most likely pull out existing pieces of the harness - at least the end connectors and do some custom wiring.
You could be correct about the housing maybe being the same. I'll check on that today for you. Or you could do it yourself at the Toyota DIY website. OpenX You can look at the fische and part numbers there.

I still wouldn't use your old axle housings under a new truck though. My reason is after 5 rolls there is a good chance that they are tweeked.

I don't think this mod wouldn't be as tough as setting up a gearset. A little grinding I imagine and maybe replacing some studs in the housing. I'd ping Christo and ask him. He could probably tell you for sure. My guesses are going off of retrofitting 80 series lockers into non-locked 80s or 60s/40s.

Making your own wiring harness wouldn't be terrible. I think there are only 5 wires if I recall correctly. I did this in my 80 series and it wasn't terrible. You might even get lucky and have parts of the harness already there.
Eric is right, I would not swap housings due to possible damage. You need the axle shaft with the long splines (passenger side) and the diff. Swap it in. Minor mods to the housing is needed. However you have a good chance the shaft might be bent as well. Wiring can be done easily. No need for ECU. We have a circuit board with relays that allows you to refroffit e-lockers to any truck and do some simple wiring.

Pull complete front diff and swap. Make sure it is still OK. I would not even bother buying harnesses. I would just take what you can from the old truck. Make sure you get the plug from the e-locker actuator to vehicle harness, ie, strip as much of the wiring as you can.

Also make sure you cut the plug for the diff lock switch. Cut the plug with as long pigtails as you can. That will make it easier to retrofit the 80 style switch. For that matter, when you get ready to trash the carcass cut all plugs that you can from the harnesses that you are leaving in the carcass. They come in handy.
Thanks Eric and Christo. I feel more confident now about swapping just the diff. Good tip on getting all the plugs and sockets from my current vehicle. That's another topic but I'll need a lot of advise on how to part out the current truck - having never done it before!

Is there an easy way to figure out whether the axle shafts on my current LC are still true? If they are visually straight is that good enough? Or is it not worth the effort / risk?

Another option is that I just swap the front diff and regear and arb the rear one in the new truck. Bit more expensive but I can get the 4.88 gears from my current diff - will they work in the non-elocked rear diff? I still have the stock ones from the old truck restore my old diff back to stock and sell it as an elocker diff.

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