Atrac grinding noise

When I am in 4L and I switch my atrac on I can hear a grinding noise when I start pushing the gas. Has anyone else experienced this or anything similar even without the atrac engaged?

 

Its not the sound of the atrac working us it? Like a super loud pulsing buzz?

 

Paging DK

 

thats your drivetrain getting fubar'd by your brakes and also why lockers > atrac

 

Even the owner's manuel covers this (as I recall)... Unusual noises are NORMAL when the A-TRAC is working... the good part is you can climb pretty much anyting your truck will clear with A-TRAC. The noises are best described as grinding, clunking, ticking but are only heard when you have a tire lose traction and the A-TRAC is braking the spinning tire to match it, with the other tire on that axle rotation.

 

Does the DAC hill descent thing kind of work the same? and by same I mean that basically the computer just rides the brakes for you down the hill rather than you doing it yourself? (I know what ATRAC is and that it has a very, very different function than DAC, just asking cuz I heard these same grinding clunking noises the 1 time I used the DAC) If that is how it works I think it is kind of a dumb feature cuz I can just use the brake pedal and make a lot less noise...

Sorry, but it looks like your question is pretty much answered already.

 

Yes...you'll hear the same grinding noise with DAC.

 

I see. That makes sense, so it is effective for really steep descents. When i first saw it I was hoping it would be a fix to when you are coming down a long mountain road and automatics don't hold you back enough and you have to ride the brakes the whole way out and overheat them. My dad and I have done that a few times in his Sierra. We seem good at finding the roads that make 4-lo too slow of a ride but not being in 4-lo is too fast... We usually just ride the brakes for a mile or two then ride in 4-lo for a mile or two and so on.

 

Brady: Instead of brakes, try lower gears coasting down a long hill.

 

Hey, I have a sister-in-law in Pocatello, she runs a bar there. We visted her in 2008... also took us to the 8 Mile Bar. lol

 

My dad's Sierra won't start to slow down coasting in first gear until you break 15mph and even then it won't slow you down much unless the road is practically level. A lot of the roads we hit you can do 5-10 easy enough but 15+ and it will just beat the hell out of you and the pickup.

Haven't been to many of the bars here.

 

Help your dad dump the GM product and get a Toyota truck!

 

I believe this is a GM trait. When I downshift in my patrol truck (Chevy Colorado) all it does is jack up the RPMs. No loss of momentum takes place.

 

I'm working on it. haha, but he told me I was absolutely insane paying 25k for a vehicle. He paid 10K for his '97 Sierra with 70K miles on it and that was back in 2000 and it even has the 5.7L vortec in it. It would be hard to find a Taco for 10K that doesn't have more miles than his Sierra right now, especially in a 4 door.

Yeah, I imagine it makes them get a little better fuel economy.

 

Is this on pavement?

 

No. This is up in the mountains. Trail would probably be a better word, but we've always just called them roads.

 

Understood...I do the same thing. Around here they're called jeep trails in the summer-snowmobile trails in the winter.

 

Pretty much.

Where are you from? You description sure sounds a lot like Idaho haha

 

I'm next door over in Central Oregon.