Got stuck...(blah)... why didn't A-TRAC function like I expected?

[Visceral]

Hey all,

Got my 03 LX stuck trying to get through some spring leftover snow. The truck sunk in the dense ice/snow and high centered.

When using the max-trax and a winch to pull it out, we kept moving the max-trax to the tires that were spinning, since there was always one front and one rear tire that was. The center differential had been "locked" and the requisite lights on the dash were on about vehicle stability being turned off.

Shouldn't A-TRAC have braked the spinning tires and routed power to the ones with more traction?

I don't want to think that I need air lockers to keep that from happening in the future... :-/

 

[Visceral]

On a side-note, these trucks are too damn heavy fully loaded. I stopped at a weigh stationon the way home and the truck was 7500lbs loaded with kids, all the stuff, loaded rack, and RTT. No wonder I sank in the snow.

 

[revoked]

ATRAC kicks in around 3k rpm if I remember correctly. Need to stay on the gas for a bit to let it engage.

 

[BEG]

Did the ATRAC light flash? Did you feel the ABS cycling on and off? ATRAC is unlike other TC systems in that you can't really fool it with left foot braking and you have to maintain a fairly consistent RPM for it to work properly.

 

[uzj100]

My A-TRAC kicks in about 1800 rpm's steady state throttle. If you touch the brake, A-TRAC shuts done.

 

[mgoblue]

throttle is the key to atrac, put your foot in it and let it work...that being said, if you were high centered you may have been screwed any way since your tires wouldn't have been able to bite.

 

[Clunky]

I wonder if you could have put the AHC in low height mode to smash down the snow, then gone into high to get out?

 

[Visceral]

I tried the AHC a few times. When High suddenly occured to me, I thought it might be genius, but nothing. Truck didnt even budge. AHC is great off-snow though.

Perhaps the throttle was necessary, but being high centered wheels were spinning with 0% throttle. Mashing the throttle seemed totally counter-intuitive. But perhaps I should have tried it.

 

[Visceral]

I never heard the brakes/anti-lock cycling or saw the ATRAC light flash at all.

 

[Visceral]

throttle is the key to atrac, put your foot in it and let it work...that being said, if you were high centered you may have been screwed any way since your tires wouldn't have been able to bite.

I think this is certainly true... but I had expected some sign of it working without the throttle.

 

[BEG]

I tried the AHC a few times. When High suddenly occured to me, I thought it might be genius, but nothing. Truck didnt even budge. AHC is great off-snow though.

Perhaps the throttle was necessary, but being high centered wheels were spinning with 0% throttle. Mashing the throttle seemed totally counter-intuitive. But perhaps I should have tried it.

A lot of people use AHC-low to compress whatever's under the car and then kick it back in to high to get unstuck. AHC also has a built in "extra high" mode when in 4Lo tha will raise it a certain amount above high when traction is lost. Presumably to prevent the vehicle from getting high-centered.

 

[Visceral]

A lot of people use AHC-low to compress whatever's under the car and then kick it back in to high to get unstuck. AHC also has a built in "extra high" mode when in 4Lo tha will raise it a certain amount above high when traction is lost. Presumably to prevent the vehicle from getting high-centered.

I've heard that, but I didn't see it doing anything useful. I did the High-Low-High thing and couldn't see a single bit of difference (I was really nicely up to my underside in spring-dense slow.)

 

[Visceral]

(snow)

 

[rjones]

Wow I could've posted this same exact post last night when I got home. Fully stock with Michelin Tour HP's aired down some and we were doing fine creeping slowly on the spring snow until we had to turn around this one big snow bank and I guess created two tracks? Seems it started packing the snow in below and then just stuck, high-centered. ATRAC came on and off but made no difference, after watching some of the ATRAC videos in the FAQ last night I think the key is that it needs one wheel with at least some traction and I really had none. Have you watched those yet? Pretty amazing and it points I think to low RPM's.

a-trac 101

My daughter has some pictures of us digging it out, will try to post them later for fun...

rj

 

[Spike555]

Perhaps the throttle was necessary, but being high centered wheels were spinning with 0% throttle. Mashing the throttle seemed totally counter-intuitive. But perhaps I should have tried it.

Throttle is key, just because its in gear and the wheels are spinning with no throttle the ATRAC has no idea that the wheels are spinning, it thinks you are sitting in gear, like at a stop light.
You must give throttle input and hold it, you don't need to mash it to the floor, just enough and long enough for the ATRAC to sense the wheel speed difference between the wheels, then it will kick in.
But again, with zero throttle, it wont do anything.

 

[viducce]

Eventually I'll go with air lockers, I've had them before they're so convenient....

 

[Hayes]

Steady throttle, around 2,000 rpm. Should have felt/seen something.
I probably would have left the max trax under the nonspinning tires and let the traction control do its work on the spinners. If you're always stealing traction from the non-spinners (by definition the ones with more traction), then you're always fooling the ATRAC to a degree.

Hey all,

Got my 03 LX stuck trying to get through some spring leftover snow. The truck sunk in the dense ice/snow and high centered.

When using the max-trax and a winch to pull it out, we kept moving the max-trax to the tires that were spinning, since there was always one front and one rear tire that was. The center differential had been "locked" and the requisite lights on the dash were on about vehicle stability being turned off.

Shouldn't A-TRAC have braked the spinning tires and routed power to the ones with more traction?

I don't want to think that I need air lockers to keep that from happening in the future...

 

[uzj100]

Turning the steering wheel back and forth to gain any traction from the side lugs can help as well as the steady throttle.

 

[f5driver]

Maybe the problem was the snow. I've been stuck is wet, icy snow and there wasn't enough traction to move the cruiser. Even with lockers all four wheels just spun. Once I aired down the tires finally bit and we got out.

 

[paflytyer]

High centered is high centered. Spring snow is tough and as soon as you spin a tire in it, you've created an icy patch underneath. No amount of throttle is going to fix that. Lockers would have just left you with 4 spinning tires. It doesn't take long for ATRAC to overheat anyway. You'd spin in the snow for 1-2 minutes and then you'd get the alarm beeps.

Hi-Lift high enough to either dig out, or Hi-Lift and place rocks/debris/branches under the tires and drive out.