4x4 conversion. Rear diff e-locker conversion.

[9mmParabellum]

Hey guys. New member here. Here is the story on how I ended up in the middle of this project, a 4wd conversion and rear diff e-locker conversion. I bought my first 4runner a few months ago, a 1999 2wd. It doesn't have any badges on it to identify trim level, but I assume it is a Limited model based on the options: 3.4 V6, automatic transmission, fender flares, leather power seats, sunroof. It was sold to me by someone who overheated the engine and blew the head gasket. He had no interest in spending the money necessary to fix it, and sold it off for a few hundred dollars. I fixed it and made it one of my daily drivers.

I enjoyed driving the 4runner, but really wanted a 4x4. Clean 4x4 4runners are very expensive around here though. I read through Phattyducks' 4x4 swap journal, and decided to try the conversion for myself. I acquired a donor vehicle, a wrecked 99 Limited 4x4 with factory rear diff e-locker. It still ran and drove, but it had a mangled body from a roll-over. So far I have swapped suspension components, and complete rear axle housing assembly with e-locker. I also had the transmission crossmember brackets welded into the correct position on the frame, and installed the 4x4 transmission and transfer case to test fitment. Everything appears to fit as it should, but I'll probably be taking the transmission back out to complete some other steps. I have removed the front drivetrain components from the donor vehicle already, but installing them will be one of the last steps for me.

As stated earlier, I know there is already some good information out there on 3rd gen 4x4 swaps in general, like Phattyduck's journal. I would like to know if he, or anyone else, has helpful information regarding my specific set-up. It seems like most people have swapped in the more typical SR5 transfer case, which is basically a simple j-shift transfer case with part-time 4wd only, on the 99 year model. My donor vehicle is a '99 Limited model, and comes with the multi-mode transfer case, with j-shift and push-button 4wd. I know this adds extra wiring and extra complexity to the system, which leads to the following questions:

Will I have to swap engine/transmission control modules for all the features of the multi-mode transfer case to work properly? I already plan on swapping the engine/transmission wiring harnesses.

Do I need to swap body control modules since the wiring for the push button 4wd, 4wd indicator light, and the rear diff e-locker appear to tie into the body/dash wiring harness?

Will it be necessary to gut the interior and swap body/dash wiring harnesses, or will my current wiring harnesses have connectors available for the 4wd push-button, 4wd indicator light, and rear diff e-locker?

Is it necessary for me to drop the fuel tank to wire up the rear diff e-locker? The wiring seems to run above the fuel tank, and into the body.

I noticed my instrument cluster does not have the lights to indicate which 2wd or 4wd mode you are in, so I will be swapping clusters too. Will there be an electrical connector available for that? Or will I have to swap the dash harness? Is the dash harness separate, or is it integrated into the body wiring harness?

Does my '99 4wd Limited model have additional modules that are not present on my 2wd model? Like some type of 4x4 module?

Do other modules, such as ABS module for example, need to be swapped as well for compatibility?


Any other tips, or helpful information, you can provide would be greatly appreciated. I'll post some pictures and updates soon. Thanks.

 

[3bears]

This thread might help
https://www.toyota-4runner.org/3rd-...ed-transfer-case-swap-issues.html#post3854598

also I have done an elocker retrofit and did not drop the gas tank.

 

[phattyduck]

To confirm Limited: Door cladding (not just wide flares) and digital climate control.

You have all the parts necessary to be successful on this project...

Worst case here is that you basically swap EVERYTHING over from the 4WD Limited to your 2WD - dash wiring, etc. Best case is your 4Runner has a lot of the parts already in place. You will just need to dig in and see what is the same and what is different on your 4Runner.

I know it sounds daunting, but the 4Runner comes apart and goes back together much easier than most Toyotas...

I'll try to answer your questions below:

Will I have to swap engine/transmission control modules for all the features of the multi-mode transfer case to work properly? I already plan on swapping the engine/transmission wiring harnesses.

The engine ECU does not control the 4WD system, though it does (slightly) modify shifting in 4LO. Once you are swapping engine/trans harnesses (yes, this will be the easiest way - you basically just have to remove the intake manifold to get it off), swapping the 4WD engine ECU is only two bolts away to match the drivetrain.

Do I need to swap body control modules since the wiring for the push button 4wd, 4wd indicator light, and the rear diff e-locker appear to tie into the body/dash wiring harness?

No body control module differences (though, maybe?) There is a diff lock ECU and a 4WD ECU that you will need to swap over. If your dash harness is missing the connectors and/or pins needed, then you need to swap the dash harness). You will need to swap the harness to the fuse box in the engine bay to get the VSV control wires.

Will it be necessary to gut the interior and swap body/dash wiring harnesses, or will my current wiring harnesses have connectors available for the 4wd push-button, 4wd indicator light, and rear diff e-locker?

Get in there and check. Probably, but not guaranteed

Is it necessary for me to drop the fuel tank to wire up the rear diff e-locker? The wiring seems to run above the fuel tank, and into the body.

The driver's side body harness (under the sill cover) is different for the e-locker trucks compared to (most) of the non-e-locker trucks. You will likely have to swap that. There is an access panel under the rear driver's side seat bottom where the harness goes under the truck for the fuel tank and rear locker.

I noticed my instrument cluster does not have the lights to indicate which 2wd or 4wd mode you are in, so I will be swapping clusters too. Will there be an electrical connector available for that? Or will I have to swap the dash harness? Is the dash harness separate, or is it integrated into the body wiring harness?

Easiest is swap the complete cluster. If you want to keep your mileage on the dash, you will have to mix-n-match cluster parts. I did not have to swap dash harnesses to get the j-shift 4WD light to work - I don't know if that will still be true on the Limited.

Does my '99 4wd Limited model have additional modules that are not present on my 2wd model? Like some type of 4x4 module?

As mentioned above, 4WD ECU and e-locker ECU will be in the driver's footwell.

Do other modules, such as ABS module for example, need to be swapped as well for compatibility?

Yes, swap them. They are calibrated slightly differently between 2WD/4WD and other options (wheel/ tire size too). It'll be a easy swap as you have everything blown apart for this process.

Overall, just assume you should swap the 4WD part over to your 2WD. That will be easier, overall, then trying to cut/splice/kludge things. When I did my swap, I had a '97 donor going into my '99, which means I HAD to cut/splice (connectors and lots of things changed between '96-'98 and '99-'00 and again in '01-'02). You don't have that challenge/limitation.

Oh, and working 5VZ's are worth good money, so make sure you sell that thing to help pay for the project.

-Charlie

 

[9mmParabellum]

Thanks guys. This is excellent information.