wonkainc

Does anyone know if it's possible to swap in a rear axle e-locker unit from a 3rd gen into a 2nd gen?

I have a 95 4runner with a 3.4 swap, but the gearing is off and I want to swap down to a 4.1 and would like to put in some diff locks. Seems I can save some money if I just buy a whole differential unit and slide them in, instead of having the existing ones regeared by a shop. In which case dropping cash on an existing e-locker + new wiring harness from a 3rd gen seems like a good option, but I don't want to do a complete axle swap and mod. So will the existing axle receive the 3rd gen differential? Everything I've seen indicates they're the same size, but I want to make sure.

I'm aware that I could just buy bigger tires, but this truck spends 90% of its time on the highway, and I'd like to keep it with 31s. Sand and snow are my concerns here in SoCal.

jsabowabo

All 3rd gen 4runners with a factory e-locker had 4.30 axle ratio. Yes, the e-locker will fit into your 8" housing, but it takes some modification. The easiest route is probably swap front and rear 4.30 gears from the same 3rd gen 4runner so your gearing matches. If you want 4.10 and e-locker, you have to go Tacoma.

wonkainc

Thank you for the info! I ended up sourcing 4.1 3rd members and am putting an Eaton LSD in the front with manual hubs. I'll save the e-locker until there's a bit more $$ in the pocket. Though now I have a pair of 4.88 3rd members if anyone wants to buy em.

Fr1tzy

Now that you have spent some time (sorry for resurrecting your old thread) with the Eaton, could you comment on how you like it? IIRC the only LSD Eaton makes for the 7.5 front is the Truetrac. Is that what you installed?

coopster

Less than a year old thread. Thats not a resurrection LOL. Its legit.

I have a 4.10 Elocker from a 99 4Runner. (door code and all)
I was/will eventually get around to putting into my second gen (Elocker part. Mine is a 4.88). Also I don't believe the front gearing from a Third Gen will fit into the diff for a Second gen.

wonkainc

It feels great. Definitely pulls to center on turns, especially sharp turns. I don't notice it at all during normal driving conditions. Granted 4x4 "normal" isn't really a thing and the manual hubs make grocery store runs truly normal. As far as performance goes, I tend to overland and am usually alone, which means I'm not entirely sure I've ever put it to its test. I haven't taken it through real mud or snow yet so that's still an unknown. It's not a dune runner, so haven't done any major sand adventures. However; I have definitely wandered about along pretty steep rutted hills with soft ash/dirt and it felt effortless. I'm convinced at this point that there is no US forestry road I can't conquer. I'm not about to follow a rock crawler and expect all roses though. Post-Covid work has required more of my time than I'd like, so there are fewer adventures and fewer modifications. I'd like to add more capability to the truck, so the Tru-Trac was added with ambition more than real need.

My rig as it stands - 1995 4runner / 3.4L engine swap with oil cooler/ r150 manual transmission/ 4.11 gears/ Eaton Trutrac front - open rear / Stock height Bilstien 4600 shocks/ 31in tires / A/C runs ice-cold

I do recommend it for a front locker. I ambitiously would like to add a rear locker (air or electronic) to the back, but there are other things to do first.

Fr1tzy

Hey we have similar setups! 1992 3.4 swapped M/T. I grenaded my front diff and I am now on the hunt for the right LSD.

It sounds like you may not have locked up your Trutrack then right? From what I have read, you need to deliberately engage the Trutrack by applying left foot brake + right foot accelerator. Have you experience any issues with it not locking up when you need it to?

I am imagining the headache of being stuck and having to feather the clutch, feather the gas pedal, and be on the brakes at the same time in order for the diff to lockup. (Maybe some toe heel racing techniques would be in order)

wonkainc

Yes, you're correct, I haven't locked up the Truetrac. My understanding seems to be a bit different than yours though because I don't believe I ever should. Based on my experience, the Trutrac is always trying to get the two wheels to spin at the same speed but allows for some variance in the wheel spin. You can feel it when you turn, it pulls you back to the center and has some real push. It's supposed to really shine in low traction environments, like mud, sand, snow, etc... It always maintains some power to both wheels with a variable split depending on the current wheel spin rates. The only time the Tru-Trac loses its value is when one wheel completely loses resistance. At which point you can force it to lock as you mentioned by applying braking force while the wheels spin, but that's not ideal. If you can't get it to lock you'll just spin your freewheel and risk burning out/breaking the worm gears inside. I haven't been in a situation where one of my front wheels was fully off the ground, nor in an icy road condition, so I've never lost it like that. It has definitely pulled me through loose shale, and some ash/sand situations that normally would have bogged an open differential. So the Trutrac isn't a black or white "locked" or "not locked" style system. It's more grey than that. like I mentioned, it's great until one wheel is in the air and then you need to do some shenanigans to artificially move power. So my build plan for rocks is to add a properly locking rear differential that I can turn on or off. Until then, I'm not planning to put myself in a situation that risky without another rig and a buddy. I hope that's helpful.

Also, sweet truck! Do you have a locker in the back?

Fr1tzy

Ah yes the point of this thread...

Before my ADD kicked in about your front diff Truetrack, I was searching for information on rear Toyota factory e-lockers. I am interested in putting a factory Taco in the rear of my 2nd gen 4R with 4.10s. I cannot seem to find a good write up on the "modifications" that I keep hearing about.

If someone could put a link to more info on these mods, it would be appreciated!

wonkainc

The factory E-lockers were only in 3rd gen 4runners, so the straightforward thing is a full axle swap. That changes your wheel width in the back, so you'd need to swap your front axle with something else. SAS is preferred if you're gonna go through the trouble.

It's theoretically possible to reuse the 8-in housing on the stock rear axle that you have, but you have to plug and weld new bolt stems to it to match the E-locker pattern, and there's also some extra welding and fabrication to get the actuator attached as well. So it's a pretty custom adventure that doesn't make a ton of sense. If you're gonna put lockers in both differentials and head into the rock crawler territory, you'll want bigger tires, which means you'll want a beefier set of axles anyway. Also, if you have the skills to weld on new bolt stems and plug the old holes, you probably have the skills and shop to just swap front and rear axles. So it starts to become an exotic solution for a problem that usually upgrades itself away. If you really want a selectable locker, the ARB air lockers are sorta the only game in town for it. If it's not a daily driver, just put one of the spartan lockers in there. Easy to do, relatively easy to undo, with all of the solutions and only a little bit of pain.

Youtube has some decent overviews, but they're usually painful to watch. Good luck!

Fr1tzy

Now that I am off work I was able to find a treasure trove of info. Putting the E-Locker into the non locked axle does not seem too difficult, but you may have to run it without the rear sway bar. I am going to share the spoils of my search here for anyone who stumbles on this thread (@wonkainc, the title of your post is too intuitive and "searchable" to not add links to). Maybe I will post info for rear E-Locker hub-to-hub axle swaps if I find good links.

Contemplating the swap and what the available options are:
http://www.off-road.com/trucks-4x4/t...wap-54205.html

Axle modifications:
Mods look to be the same regardless whether you are converting an unlocked 2nd gen or an unlocked 3rd gen 4Runner (not sure about 1st gen)
http://www.sonoransteel.com/phong/re...r.html#housing
http://www.4x4wire.com/toyota/tech/electric_locker/
https://forum.ih8mud.com/threads/8-r...stion.1233598/

Wiring:
https://www.yotatech.com/forums/f131...ations-234291/
http://www.off-road.com/trucks-4x4/t...t-2-54239.html

Misc. Hardware:
https://www.yotamasters.com/shop/dif...tial-gasket-2/