4low-trac

trac in 4lo can not be added to trd or models. the 4wd cpu is different. the wiring is different. also, this mod is especially useful for 4cyl trucks. i dont have enough torque to do what i do in 4hi. I neeeeed 4lo.

Trac applies the brakes alot slower and requires quite a bit of wheel slippage before the brakes come on hard. I think my Trac works really good but it is in fact different than atrac. same principles different follow through.

 

Thanks Yoytoda!

 

just trying to help out. Believe me i tore my hair out at first trying to figure it out. when i was at the dealer they told me the auto lsd is a mechanical type in the front and rear i was stoked till i got home and read the manual on my new truck. i was ready to take the truck back and tell them they better make right on them misleading me until TW. the yellow wire mod is amazing and works better than any lsd ive had in any of my off road trucks. im still going to put lockers front and rear. The best part is the auto lsd is only in the brake system so even if i have lockers front and rear and have them in the open posistion i still have lsd. then when the wheels are lock i dont have to worry about trac kicking in because there wont be and wheel travelling faster than any other. then id have an amazing combo and infinite driving capability on and off road.

 

Funny that they don't take the time to learn their product or read Tacoma World!

Still would like to hear from Hemi... my newest/ revised questions after your input is:

1) AUTO LDS (in H2) and A-TRAC (in L4) both work using the same mechanical principals?

2) TRAC (in H4) works differently, using the mechanics of TRAC in H2, except without power regulation?

3) With the yellow wire mod (to non-A-TRAC trucks), you get TRAC in L4, but not the same as A-TRAC... (TRAC being a milder transfer of torque to traction tires and A-TRAC being a suddon transfer of troque)?

 

TRAC in 4L is like Auto LSD on both axles, smooth, effective, quiet. Very similar to mechanical LSD with some tradoffs. TRAC allows a some RPM between wheels. Requires a fair amount of throttle to be most effective.

ATRAC which only functions in 4L is like having mechanical (not pneumatic like ARB) lockers, where once a small amount of slip is detected, it grabs. It is far stronger than even the tightest LSD. It essentially locks the wheels to the point that there is almost no rotational difference between wheels on the same axle. It also makes a bunch of noise and vibrates. Not a big deal, really. My opinion is it is better under most circumstances than true lockers. Deep mud might be a different story, but given that it kicks in automatically, doesn`t bind, and is very effective, that is just speculation.
As for adding this to the Off Road model.....no point really. ATRAC is superior, but this thread is about TRAC, and debating the superiority of ATRAC is getting off topic......

 

Okay, thanks for this... Perhaps I will start another thread, but I think it is related.

Can you tell me how TRAC in L4 (yellow wire mod.) that you say is like AUTO LSD on 4 wheels is different than TRAC in H4?

The use of the word 'TRAC' may be confusing if TRAC in low range isn't working the same as in high range?

I thought we were getting real close to understanding all this until you said A-TRAC was different than how AUTO LSD works, which is different than how TRAC in H4 works... right?

Time for a drink?

 

Trac is auto lsd. TRAC in 4hi/4lo is lsd front and rear.
trac in 4hi is the same as trac in 4lo.
all of these systems use the brakes so they are all the same principle.
The only difference is ATRAC which is much more sensitive, allowing a fraction of the wheelspin of trac. It is still "auto lsd",because it uses the brakes, front and rear but alot less slippage.

 

Thanks Yoytoda...

It is really bad the wording Toyota uses for these features... I understand what you are saying... BUT, 'TRAC' and 'AUTO LSD' are different (in 2WD)... Because when you turn TRAC off in 2WD, AUTO LSD comes on, for heavier braking to get unstuck in 2WD.

Maybe in 4WD (H4), TRAC becomes the same as 'AUTO LSD' as there is no power regulation in H4, as there is with TRAC in H2... ???

Time for another drink!

 

you are confusing trac with vsc

 

vsc is the car with swervy lines. when you press auto lsd vsc "vehicle stability control" turns off. vcs prevents wheel spin. it does not aid traction. vsc is on in 4hi with hardly any intervention. it is off in 4lo. technacally trac is the combination of vsc and auto lsd. press auto lsd in you truck and go over 35mph, the vsc light goes out but the auto lsd light stays on "TRAC in 2HI"

 

Bottom line the yellow wire mod works awesome. Once again to those without trd Offroad model 4x4 trucks 2009 or 2010. this mod transforms a normally open-open truck to essentially lsd-lsd.

 

Awesome!

 

OK my 2009 access cab sport 4wd v6 with manual trans displays a blinking 4wd indicator whenever I go into 4 low. It has always done this and I have not cut any wires at all. Does this mean that the trac is already on in 4 low in my truck or is there something else going on here? I have only used 4 low getting my boat out at one ramp in particular where it is very steep and there is a lot of algae everywhere so that it is really dificult to pull a boat out if not using 4wd. 4 low jerks it outtathere like nobody's business!

Very interesting thread and I will most likely look into that wire to see how it is landed and why my indicator already blinks like yall say it does when the wire mod is done?!?

 

Blinking means NOT engaged... the indicater will be solid when engaged... You have no TRAC unless you did the yellow wire mod... But, if your truck actually moved while blinking... and had low end toque (low range)... ????

 

^^What David said.^
There is only 1 thread on this subject, let's please keep this on TRAC, (pun intended). Thanks fellas.
Any more mod stories? Anyone?

 

Well, to give the guy some slack, the 'yellow wire mod' causes the 4-lo indicater to blink... right?

 

I know, just a friendly nudge back to mod land...

 

Well I have not done the mod yet but will...and the indicator DOES blink in 4 low just like was said it would do so this is a valid question in this thread. And no doubt it is in 4 low it just pulls like a tractor it would be nice to know what the crawl ratio is in 4 low for these tacos...

I still have to wonder why the indicator is blinking in 4 low; it does not do it in 4-hi so WTF?

 

Take it to the dealer... blinking means you are not in L4 (Hemi confirms and he knows)... perhaps you are in L2, and that is why you feel the low gearing torque?

 

Correct. I tried playing with it some more and found out the actuation from 4 lo to 4 hi ot the other way has to be done with the clutch in. So it is working as advertised. Sorry for the thread-jacking...