TFPracing

iTrader: (4)

2001 GMC SIERRA C3
Is there any problems to watch for in these trucks
lq4 awd fully loaded

airaidslayed

Yes, the front and rear differential carrier bearings were engineered too small. It is very common for the carrier bearings to go around every 20-30K miles and consequently tear up the carrier and gears. Change your fluid very often and suggest running Red Line H/D fluid. Good Luck

SHINER

iTrader: (18)

How bout the 2002 Sierra Denali? Did they fix the problem during this year?

The Sierra C3 was renamed the Denali in 2002.

1Bear

iTrader: (1)

I would just drive the truck, listen for any noises out of the front end. Then if you can have the front diff's fluid drained to see if any metal is on the drain plug. The same front diff. was used in the C3, Sierra Denali, Yukon Denali, Escalade and SS trucks and is known for having weak pinion/carrier bearings. I wouldn't be to concerned with the rear diff. as long as there is not any poping or jerking going on. The rear is the same as all the rest of the 1/2 tons. Outside of that, I would say they are very good trucks. I have had mine for over 105K miles and outside of grenading the G80, transmision finally giving up the ghost and having to rebuild the front diff. only a couple of lights have burned out in some switches.

SHINER

iTrader: (18)

1Bear,
Im pretty sure are trucks that have the quadrasteer are different from halfton trucks. They are a 12 bolt axle modeled after the Dana version. Very good rear axles.

I was also reading that the noise doest mean the front differential will fail, and GM says "if you can live with the noise, then your fine. Other than that nothing should fail/break"

People say its the bearing but i have heard otherwise, and that the noise would go away if they changed the pinion out with the updated one.

1Bear

iTrader: (1)

Shiner, your right about the rear in the SD's '02 thru '04 as they were quadrasteer's and use the Dana 60. I was speaking of the C3 when I said they were the same as the other 1/2 tons, sorry about the confusion. But the front is the same as all 1/2 tons without the 4wd actuator, in that they use a one piece right side axel. It appears not as many people complain about the front ends in the Denali's & Escalades as they do in the SS trucks which may be how they are driven or that the SS's came with 20's and don't really like the additional strain on a daily basis. And as far as nothing should not fail/break, I guess that would depend on if it was just gear noise or bearings actually coming apart, there are quite a few with just gear noise.

SHINER

iTrader: (18)

well the its gear noise because 99% of all the C3/Denali guys say the noise immediately goes away once their foots are off the gas pedal and if it were a bearing problem the noise should be constant('round the clock)


So are our trucks FULL TIME 4WD or is it a Auto 4WD and is in 2WD most of the time and then sinces slippage then the front differential engages?

1Bear

iTrader: (1)

Our trucks are full time AWD with the NVG-149 transfer case distributing the load via the viscous coupling which is what keeps the front from hoping around on dry pavement like a true 4WD would end up doing. Now the NNBS '07 trucks and the '03 and up Yukon Denali and Escalade use a Borg Warner transfer case that acts as an open differential in conjunction with the ABS to control the AWD functions.

SHINER

iTrader: (18)

oh...which is better..lol Who makes NVG?

1Bear

iTrader: (1)

New Venture Gear and I tend to believe ours is probably the better unit, as it is mechanical in nature and not dependent on all the electronics (ABS and such). By the way I've only heard of a few failing and the majority of those were beat on.