ManyMods

If you have any interest in a LIMITED SLIP DIFFERENTIAL for your 4Runner, this is a must read.

I have been running a thread titled EATON LSD for 2002 4Runners. I have had an EATON LSD unit on order for about a year and finally received it this week. I am always skeptical about after market performance parts. Therefore, I do extensive research and direct inquiries with manufactures because I am fearful that I will be an extension of inadequate R&D and something will go wrong or not as represented. I was assured by two engineers at EATON TORQUE CONTROL that PN 19614-010 would fit without any modifications, shimming, etc.

After taking the rear end completely apart, the side bearings did not transfer onto the new cage and the difference was about .04 - .05 too big, plus the height was about ¼ inch too high on the new unit. I won’t bore you with any of the back and forth vain attempts between EATON and my mechanic to figure this out, but the end result was that my differential is back in its original assembled condition and the EATON LSD is being returned to the Mfg.

The unit referenced above was intended for the TRD pickup trucks and it was “assumed” that it would fit the ’96–’02 4Runner. To add to the misery you and I may experience, PERFORMANCE PRODUCTS is inaccurately advertising (what else is new) a TRD “manufactured” LSD unit for all ’84–’02 4Runners. That unit is made by EATON and it will not fit. EATON also used to make the LSD units for Toyota but they do very little for Toyota these days and Toyota does not offer an LSD unit for our 4Runners.

EATON has just purchased Tractech Inc and they recommended that I might look into an LSD from them http://www.tractech.com/Products.htm#slip or an ARB RD23 from Drive Train Specialists http://www.drivetrainspecialists.com...duct-2394.html. I am not sure I am going to pursue this any further so I do not know if there is even an application for our 4Runners. EATON is not going to make any revisions or manufacture a unit for our trucks because we are an expiring niche market.

EATON has been very gracious and has taken responsibility for all the inconvenience and hardship they have caused me. I hope this information saves you from what I have gone through.

ebelen1

It's kinda ironic that the new PP catalog now does not have the 3rd gen runners in the TRD LSD advertisement. Just six months ago, it was available for the 3rd gen runners and was on page 2 of the catalog. Now, all the TRD LSD units are marked down almost half price from $450 to $280.

ManyMods

I am not really surprised but cannot imagine how many other people were inconvenienced to the degree I was. I insisted that Summit Racing issue a call tag for the return of the EATON unit and besides reimbursing me for the entire cost of the unit, also credit me for the piddly $9.50 handling charge, just on principle. The shipping to me was FREE. As I said before, EATON acted very apologetically and reimbursed me for all my other expenses.

I have not received my PP catalog yet.

jeremys73

get the tractech ManyMods, you waited a whole year for a LSD, I vote that you get one after this whole ordeal...

ManyMods

Hi Jeremy,
I guess what troubles me is that I do not understand the characteristics of the TracTech and am therefore afraid that it will be different than what I am used to, that being a simple LSD type rear end. EATON told me that the characteristics were different and you needed to apply the brakes when one wheel started slipping? I can research it when I have time if you all are telling me it is the same as any other LSD, but I just don’t have the stomach right now to endure another debacle.

jeremys73

I'm not sure how it works. i think you do the brake thing only if you get a wheel in the air. I think it works normal with both tires on the ground.

https://www.yotatech.com/forums/f2/front-locker-lsd-suggestions-75491/

EnolaGaia

Correct... The 'apply brake' tactic only applies when one wheel is completely nullified (e.g., off the ground, in the air). Tapping the brakes basically tricks the mechanism into allocating power back to the other wheel.

Basic advantages of the TrueTrac:

- Gear-based rather than clutch-based
- Theoretically more durable (since no clutches to wear out)
- No fluid additives (friction enhancers) to add

Do some Googling on "TrueTrac" - there are plenty of reviews out there (the vast majority of which are positive).

ManyMods

Thank you for your very succinct explanation and suggestions. One question: For a vehicle that essentially does no off-road duty and quiet often cruises interstate highways at +70 mph on dry pavement; are there any adverse effects from this gearing?

EnolaGaia

Not sure I'm sure what you're asking......

(a) Adverse effects from *gear-based* LSD (vs. anything else). Basically - No. Unless you get in a torque-differentiated state that triggers the mechanism it basically feels like an open differential. There are multiple reviews out there with comments about its smoothness and how you don't even know it's there in normal use.

(b) Adverse effects on *gear ratio*. No. Standard install procedure is to transplant your ring gear into the TrueTrac - preserving your current ratio.

(c) Adverse effects on 'driving feel / behavior'. You should expect a more positive 'grab' when pulling out hard (which is why LSD's are popular with street racers), because both wheels will be more equally sharing the work.

LSD's are popular with some auto-crossers, based on being able to apply power earlier coming out of a corner.

I've seen some claims that LSD's may be slightly more prone (than an open differential) to let the rear end 'break away' under certain extreme sliding / cutting conditions. I'm not sure how much stock to put in such comments. In any case, there's no way it's as bad as a locker in this respect. If you're operating that close to the edge, you need to know how to slide anyway.... ;-)

Hope this helps.....

ManyMods

Great stuff You certainly know your stuff You've got my interest and convinced me to investigate this with the mfg.

THANK YOU!