4wd Lo Problems

Volucris · November 9, 2007

Hi,

I have a problem I hope you can all help me with. I have a 2007 1500 classic, crew, 4WD, LS. I drove abount 16 miles the other day on a rocky snowy mountain road in 4WD low range. When I got back to the hiway I stopped, put it in neutral, and shifted into 2hi. The transfer case shifter is on the floor.

Something stuck. I could no longer put it on 4wd lo or hi (or at leat the indicator light wouldn't come on). When I put it in 2wd and drove on the hiway, there was a lot of mechanical drag until there was a god-awful clunk from under the vehicle, and then it drove fine. The clunk definitely sounder like something that was stuck releasing.

I took it to the dealer and got the "we can't make it happen here so we can't fix it if we can't tell it's broke" response. Do you all have any idea what this might be? The truck only has 14,000 miles on it, so this is pretty dissapointing.

Another thing. When I'm driving in 4lo, there is quite a bit of noise. Is that normal?

Thanks,

Volucris

asilverblazer · November 9, 2007

4 LO is noiser from the additional gears turning (Almost like reverse but not as noticeable.) It sounds like the linkage bound up, and went from 4LO to 4HI, got stuk in 4 HI, enev though the lever was in 2HI, once it freed up it shifted to 2HI, making the loud clunk.

Silverado4x4 · November 10, 2007

Where you driving in a straight line when you stopped to put it back in 2h? If you were on a turn then stopped then the front hubs could have been bound up some and when they got back in sync the hubs released and you heard the clunk. Yes 4L is loud also 4L should only be used in deep mud, sand or pulling something out of the ground, 4H for snow driving. 4L doesnt give you no more traction all it does is reduce the gearing for more torque to the wheels.

Genuinefine409 · November 10, 2007

Another thing about 4Lo, it can be very unforgiving on axles and diffs.

Volucris · November 10, 2007

Yup, I was driving in a straight line when shifting, about 1 mph or less, and had it in neutral. I'm also well aware of when and where to use 4lo vs 4hi. I've been driving 4WD's for more than 20 years and know how and why to use them. 4LO is also used on steep rocky roads so that you can crawl up and down them with out having to rev the engine or ride the brakes, which is what I was using it for.

Believe me, this was a mechanical problem somwhere and far from normal. Of course, this is my first GM 4WD, so what the heck do I know?

Volucris

azswede1960 · November 25, 2007

Yup, I was driving in a straight line when shifting, about 1 mph or less, and had it in neutral. I'm also well aware of when and where to use 4lo vs 4hi. I've been driving 4WD's for more than 20 years and know how and why to use them. 4LO is also used on steep rocky roads so that you can crawl up and down them with out having to rev the engine or ride the brakes, which is what I was using it for.

Believe me, this was a mechanical problem somwhere and far from normal. Of course, this is my first GM 4WD, so what the heck do I know?

Volucris

My 2003 seems to be very "grumbling" in 4hi .... I have not used it for a while but it did not use to be like that ..... I am going to find another owner with Z71 from same/close year and ask for a ride to compare, but i am faily certain that something is dragging, almost working against itself ....

Any suggestions?