Jeff B. in Michigan

Just FYI for those who struggle to find a LSD that will fit a 1998 +/- 4Runner. I had trouble finding anything that would fit. I even called the tech support group at Auburn, TRD and EATON with no luck. I was ready to spend the $900.00 ++ to get the TRD unit direct from Japan (TRD US would not even sell it to me because it is not specified to use in the US 4Runner). Anyway, I contacted Randy's Ring and Pinion thanks to a tip from Phong (thanks).

Randy's Ring and Pinion confirmed that the Detroit Truetrac unit part number 913A321 would work in my 98. It was installed last week and works great.

Nolan

is it the rear true trac? but anyways how do you like it? what are you impressions of it? what will you use it for mainly? do you have 4wd or 2wd?

Albuquerque Jim

Cost please???

turboale

Hes using it for traction... though for him... he needs traction because he has too much power, not because the surface is soft And, what about a locking diff? Will it not hold the power or something? You could just lock it up when your doing your runs then at the end of the run let it free...?

Albuquerque Jim

I am thinking there is a cool possibility here. An LSD in the rear (I have a S/C too) and an ARB locker in the front.

Because I am on-road much more than off. But when off-road I want to be able to go wherever I want to. I realize an LSD isn't as good as a locker for off-road in the rear, but I think it's a good compromise.

What do yo guys think?

turboale

I think that would be fine. Its been done many times, but its usually the other way around b/c I guess they get the acclaimed factory e-locker and go with the soft locker in the front (ie lsd). The only difference is that why do you want an lsd jim? If your going to get an arb you might as well go f/r since you are getting the compressor and all of that anyway...? He is using his for completely different purposes, not b/c he has an s/c but b/c hes going to be taking his truck to the drag strip and needs traction. If you really need more on-road traction or if your strapped for cash (i think they are a little cheaper) then get an lsd, but if your going to just use it for 4x4ing, then go with dual lockers.

Albuquerque Jim

Both of those apply...but I also think it's a way to have 2-tire burning street ability and (better than open diffs) off-road ability. The best of both worlds.

I know that 2 lockers is best for off-road. But, I enjoy my 4Runner with the S/C on the street too. I am 98% on the street. The only thing I don't like about the set up is the lack of control in the mud or snow (not that we get a whole lot of either here) the back end can come around pretty quickly with a LSD.

I mainly wanted to throw this out there (sorry to hijack the thread) for discussion.

OpieJoe

Hey guys,

I have been running a TruTrac in the rear of my 96 Runner for about a year and a half now. I really love it on the street, very good manners and it works really well at the drag strip. The truck launches straight and never pulls to the side. People are amazed to see a grocery getter going so fast. I usually launch the truck in 4Hi because of the excessive wheel spin in 2Hi and then pop the button out just after I launch. It comes out of 4Hi at the top of first gear. I have actually spun all 4 tires before and really suprised a bunch of people.

I had a Detroit locker in my 85 Runner and that thing would really buck you around sometimes. It was great off road, but on road, you really know that it is there. If you are going to wheel hard, get a full locker. The TruTrac will help off-road, but still isn't 100%. Just let me know if I can be of any further help with your decision.

Brian

Woodbert

I have the Toyota factory rear TORSEN LSD and selectable 4WD HI/LO with center locker in my 4th Gen. I can also run in 2WD when I want some extra GO.

I use it in beach sand ALOT and have not been stuck yet and have never had to go into 4LO.

I also lock the center dif when on a slick boat ramp to get the 50/50 traction. Normally, in 4WD HI the power is distributed 60(R)/40(F).

The REVO's help in all the conditions as well.

Nolan

how does an LSD do in the ice, wet pavement, and sand?

Jeff B. in Michigan

Here are some more details:

My post is relating to the rear LSD

Cost for the LSD = $ 350.38 Randy's R&P (1.800.347.1188)
Cost for the install kit (Yukon) = $119.03
Cost for the actual installation = $180.00

LSD is not so good in the snow and ice, you have to be really careful during acceleration and deceleration.

I bought it to give me more traction on the street. I believe it would be better than stock open diffie for off road until you get one of the rear tires completely off the ground. If there is no load at all on one of the rear tires, the LSD will not lock in the other wheel. I did a test of my LSD after it was installed. I placed one side of the truck (both tires) on the grass and the other side of the truck on dry pavement. I gave it a bit o gas and both rear tires broke loose. The rear of the truck started to swing towards the grassy area due to the uneven road surface.

Jeff B. in Michigan

Say Brian,

Good results in the 1/4 mile time & MPH.. How did you set your injectors up? Specifically, I would like to know what AFR you are experiencing through a run.

Thanks,

Jeff B

FYI... This is what I got yesterday using stock injectors & fuel pump and 9.8psi pulley: Also FYI.. my best time with stock pulley, injectors and fuel pump is 15.02 @ 89 MPH

OpieJoe

Jeff,

I am running my AFC at the settings that Creed suggested. I am watching the voltage from my stock narrowband O2 sensor through the AFC, but know that is not good enough. I was looking at your wideband info and will be ordering one of those shortly. I know that I am running pig rich because the plugs show it and so does the tailpipe. I figured it was better to run that rich than to run it too lean and risk hurting something.

Creed had the same setup, but I know that everyone's trucks are different and I should have invested in a wideband a bit sooner. I have just leaned out my AFC a bit and I have picked up about 1MPG. I am curious how rich I have been running it and see what a better tune will afford me at the dragstrip. I would also like to see what I could get for a better time if I ran stock sized tires. I would also like to try Gadget's water injection when he gets it done. Hey, every little bit will help if I can squeeze a few more tenths out of it.

Talk to you later.

Brian

OpieJoe

Jeff,

I forgot to ask, is your truck a 4x4 or not? Just wondering if you have tried to launch in 4Hi yet?

Brian

Jeff B. in Michigan

Brian,

My truck is 4X4 and I have thought about using it for the launch just like you do. I was super disappointed this spring because I had just installed a CENTERFORCE clutch (yea, mine is a 5 speed) and was looking forward to getting it into the 14's with the stock pulley etc.... but ... the clutch would not hook up for ˟˟˟˟˟. I now have the ACT 6puck full race clutch... it is a trick to launch during normal driving but it seems to hook up with no trouble.

I live 9 miles from a really cool dragstrip in MI (US 131 MOTORSPORTS PARK). I plan to run it as soon as they open in the spring.

I agree with your plan to use the wide band O2 to dial in your injectors, it is the ONLY way to do it. Considering the cost factor, the INNOVATE MOTORSPORTS unit is the very best on the market due to it's datalogging ability. Based on my experience, the best way to really dial it in is on the street (really the dragstrip) using a datalogger. The DYNO will not provide sufficient data to properly tune everything up for the full spectrum of operation.

Good luck, keep me posted ( I bet you will blow the 14.7 time away once you get it tuned in... unless you were very lucky in the initial setup using the narrow band ... :-)

KZN185W

iTrader: (1)

Will it be alright to install a Detroit TruTrac to both the front and the rear diffs on a 3rd gen? Will I encounter problems with this config?
Is the TruTrac with part number 913A321 the only one that can be installed on a 3rd gen? What is the TruTrac part number for the front diff?

Somebody, from another forum, told me that it is needed to preload the gears when setting the gears. Is this true?

Thanks.

Flamedx4

The Truetrac is great in the front because it operates so smoothly (gears instead of clutches) In fact most of them go in the fronts. (Detroit Locker in the rear and Truetrac in the front is the classic sweet setup.) BUT - If you primarily drive on the street, and especially if you get snow and ice, you might not like it. I ran TRD limited slips front and rear in my 85 4R and I would never do it again for my daily driver. In snow and ice it was very difficult to drive - all 4 wheels wanted to go the same direction all the time. Ended up driving like a rally car - pitch it and gas it, let it slide around till I was pointing the direction I wanted to go, then gas it again. Had to drive much slower than normal to be sure not to go sliding around.

I put a TRuetrac in the rear of the Flamed truck, the third is sitting there ready to bolt in tonight. I chose it for it's smoothness.

KZN185W

iTrader: (1)

Yes, I'll be using it primarily on the streets. On some weekends, I go on mild trailing.

There's no snow or ice here in the Philippines. Will I still have probs if I put a TruTrac in both the front and rear? What sort of problems can i expect?

Thanks again.

Flamedx4

Since you probably don't ever need to use 4wd on the pavement or at highway speeds, it would probably be terrific for you! Excellent traction and smooth operation.

Albuquerque Jim

Front 3rd gen Truetrac part # 911A342

I find it works very well in the front, but I have a selectable locker in the rear too.