Converting Clutch-Based LSD to Geared LSD on a Tacoma PreRunner

-the stock clutch LSD is designed for 265/65r17, not above.
-the stock clutch LSD is probably worn out
-the stock clutch LSD has a wear clutch. A truetrac does not.
-the stock clutch LSD is worth little, if anything, let alone compared to performance part such as a Truetrac. Or ARB air locker. Or eaton e-locker.
-having had both, a Truetrac performs noticeably better.
-a TrueTrac is much more affordable than a locker, which does not give every day performance turned off; only off road when it is engaged. A locker costs twice more for the locker, before factoring in anything else such as air compressor to activate it.
-rotating is the part of the point of an LSD and how a car should be. If a person cannot initiate and hold a full opposite lock slide for an infinite amount of time, they should probably not have a license. This is mandatory for children in Finland to pass a driving test. And can be learned for free on a video game. An LSD is probably safer than not having one because it responds to driver input rather than shitting it's pants.

looks like a healthy amount of crack smoked in the above post

I am not against ARB air lockers, Eaton e-lockers, etc.
to say the stock LSD is good, or that an LSD is dangerous, is cracksmoke

 

OP, the axle code for my son’s ‘06 TRD Sport (which has the factory clutch LSD replaced with Trutrac) is code ‘A04C’. It had (still has) the vertical LSD sticker on it matching an earlier post. Again, the Trutrac is fantastic in the real world if you decide to go for it.

You can find the axle code along the bottom row to the left of the transmission code (A750F).


.

 

You can find this on the door jam sticker also. The code A04C stands for LSD?

 

Yes the C denotres it has the lsd

 

Just wanted to give this thread a bump and say thank you for the input and great info here.

I have a 2008 TRD sport with a LSD and I'm getting a bit of chatter turning on dry pavement.

Not sure what oil I've got in there but I'll be swapping the fluids in the diffs and transfer case within a couple weeks. Hopefully this will solve the issue but if it doesn't now I know I have a cheaper option with the Eaton lsd diff.

I now also know that I have the 8.4" diff.

 

Did your son notice any significant difference after upgrading to the Truetrac? I asked Eaton about it, and they told me I dont really need to upgrade because the factory "POSI" works similarly to a Truetrac.

 

if you don’t know what fluid is in there you need to change it.

the TrueTrac is better. And probably handles bigger tires. The factory mech LSD was designed in a 265/65r17 tire size truck.

if a person is regearing and/or upgrading their diff it doesn’t make sense to leave in there something like that let alone it being old and worn out.

question is if you want a mech LSD (such as TrueTrac) or something else like Eaton elocker, arb air locker and associated required supporting parts, etc. they each have pros and cons.

 

I ran the truck with the TrueTrac for a couple years and he has had the truck for 3 years now. It is fantastic and seamless. In the real world on road and off road it is seamless and extremely effective. It is especially effective in snow.

If you have an ultra hardcore rock crawling rig then selectable lockers are great. For that use buy a dedicated trail rig.

It rocks.

 

My 07 tacoma prerunner (V6, 2WD - not TRD Sport) shows a similar axle code except for the last digit. What size Ring Gear does it have? Also, what do you guys think is the best gear ratio for running 33s? I occasionally go off-road, but I mostly use my truck for commuting.

 

non ELD is 8.4 3.73
Non TRD Sport = open diff

Ideal for 33 probably 4.10, 4.30, maybe 3.73.
Depends on auto or manual. Manual has 6 gears. Auto has 5. The driveline runs through those gears. Many of them are different ratios.

Edit: nvm. Sticker A750 tells me auto. Supposedly doesn’t need quite as “high” number of gear ratio as manual, digit-wise.

odds are you know by now how it feels. If it’s cruising too high. Too low. How it cruises/speed. If it’s too fast or too slow. How it shifts. If it lugs. How it is up hill. Use cases and so on.

In your case you are probably better off starting first with the following which should probably be done regardless.

1. tune
2. Intake spacer
3. Making sure you are running flexible load C and not stiff much heavier load E made for Ford F350 diesels towing 40k lbs where people pretend they’re invulnerable (they’re not, my old load E punctured from the tiniest of screw I picked up driving through a random apartment complex parking lot)

even if you regear, you are probably still going to want to do those things.

if 4.10 works, you might be able to cheaply slap thirds in from a manual 4x4 2TRFE though that is not a common vehicle to find being parted out.

for me it was obvious my truck needed something closer to 4.56 or 4.88 because manual, 35’s, weight, etc.
with having gone 4.88 it seems slightly overgeared, but at this time I don’t see now it’s an issue as it does not cruise 90 on the highway like a BMW nor should it.

 

Had a TruTrac on my old truck, I loved it. I'd also love to put one in my current truck. I think for a weekend warrior, or someone who likes the trails but doesn't get there often but still daily drives, a rear TruTrac and selectable front locker would be a killer combination, along with proper throttle and steering input.

 

The factory gear ratio for the 2nd-generation Toyota Tacoma V6 is typically 3.73. The TRD Off-Road models came with 4.10 gears, and the stock tire size is around 30.5 inches. I'm already running 33s (Load C) with a 3.5" lift and a K&N Cold Air Intake. I feel like 4.30 probably won’t recover much of the lost torque, but 4.56 might be the sweet spot. This could be a good balance between daily drivability and off-road performance.

 

pretty sure V6 is 3.73. That’s on you to figure out.

folks with 4.56 run 35’s.

 

The 3.73 gear ratio comes as factory gear ratio for V6 with 30.5 size stock tires. Like I mentioned, I now running 33s on my Tacoma, so it make sense to go with 4.56 gears, as shown in the table below.

The 2nd-generation Toyota Tacoma V6 (2005–2015) primarily came with the following factory gear ratios:
1) 3.73:1: This was the standard gear ratio for most V6 models (PreRunners and non-TRD trims).
2) 4.10:1: Commonly found in models equipped with the TRD Off-Road package.

Most Common Gear Ratio Upgrades from 3.73:
Upgraded Gear Ratio:------Best Matched With:-----Why People Choose It:
4.10 (mild upgrade)-------Up to 32" tires-----Closest to stock powerband with slightly better torque.
4.56 (most popular)-------33" tires------Restores lost torque & throttle response. Great for daily plus off-road. Most balanced option.
4.88 35" tires-------- Regains low-end power with larger/heavier tires. Popular for lifted, trail-focused builds.

 

Many 6spd manual 4x4 3rd gen Tacomas and auto 2TR 4cyl powered 4x4 3rd gen Tacomas came with 4.30 gears from the factory, so it is possible to find a cheap junk yard 4.30 front diff off the right truck then re-gear the rear (since the 3rd gens have a bigger ring gear and aren't directly swappable). I found a used 4.30 front diff for $400 and then had ECGS re-gear my rear and add a True-Trac with the money I saved on the front. I'm also running 33's and appreciate the torquey lower gear ratios from stock.

 

sounds like a possible solution to 8” rear folks (it’s supposedly weak); if they are planning on diff type change and regear, to potentially swap in an entire 16-23 rear end. I’m guessing the only difference is that bigger size. 8.75” I think.

Maybe everything else on it like track width, SOA mount, drum brakes etc is the same.

 

Yeah someone here on TW did a 3rd gen rear axle swap on his 2nd gen and documented it. I think he added a lockered axle from an OR to his non-lockered SR5. Not sure how complicated it would be if you add it to a 2nd gen Off-Road though.

 

Would it be more complicated on an offroad?

Am I missing something?... I would think less complicated? since the wiring is already in place?

 

4x4 ecu, A-trac, ADD, etc. are increasingly more complicayed in the 3rd gen. Because of that, I'm speculating that it's unlikely just a plug and play kinda deal but I haven't actually researched it since I stayed with my SR5's 8.4" diff and installed a True Trac.

 

Ah ok yes... quite a bit to consider.

I cant imagine it not integrating and just being activated and locking when needed... but reality doesnt always agree.