Strange jerking in 4 wheel drive making a slow left turn

[unclelala]

Just started up my truck and have not had it going since early December.
It was making a chugging / jerking action when making a slow circular left hand turn which felt it was on the passenger front.
I checked the tire and found nothing.

I got back in the truck and notice I some how put it in 4 wheel drive. I put it back in 2 wheel drive and it stop and was fine.

So what was that all about? Is it something wrong with the 4 wheel drive?

 

[Ziggy]

Just started up my truck and have not had it going since early December.
It was making a chugging / jerking action when making a slow circular left hand turn which felt it was on the passenger front.
I checked the tire and found nothing.

I got back in the truck and notice I some how put it in 4 wheel drive. I put it back in 2 wheel drive and it stop and was fine.

So what was that all about? Is it something wrong with the 4 wheel drive?

Your front differential is not a limited slip, therefore the outside wheel is trying to turn faster than the inside. You should only use 4WD on slippery surfaces where the wheels can slip (ice/snow, mud, sand). Otherwise you will tear up your axle.

 

[unclelala]

Ive only used my 4 wheel once in 3 and a half years on a hell of a snow storm but must of accidentally put it in 4 wheel.

 

[Dinky503]

are you on pavement, concrete, or even gravel? this will happen in 4wd and is the reason to never use 4wd on solid surface.

 

[unclelala]

are you on pavement, concrete, or even gravel? this will happen in 4wd and is the reason to never use 4wd on solid surface.

I know all of this but it was that I accidentally turned it on 4 wheel but thought I was in 2 wheel drive then saw it was on and turned it off,
so I thought it was making that noise in 2 wheel drive.
What I didn't know that if on dry pavement it would make that grinding sound.

 

[jsalbre]

On an HD truck as long as you aren’t loaded way heavy and don’t do it for very long it likely won’t hurt anything other than wearing your tires a little bit . It’s called “crow-hop”, and it happens because the front and rear wheels need to turn different speeds when you’re turning (because they’re following different sized circles on the ground), but can’t because they’re locked together. Something has to slip and it’s almost always going to be the front tires.

U-joint axles also contribute a lot to this as a shaft driven by a U-joint that isn’t straight actually speeds up and slows down through its rotation relative to the other side of the shaft.

The left side of this animation is turning at a constant speed, but the right side can’t.


The solution to this is a double-cardan joint, like you see on some driveshafts, which is just two u-joints joined together, or an rzeppa “CV” joint (like at the transfer case end of your front driveshaft). Both joint types end up with both shaft ends turning the same speed (well, almost, there’s some error with the double cardan, but it’s not enough to matter for vehicular purposes).

RCV makes high end CV joint axle shafts for our trucks. They’re expensive, but very strong.

Anyway, this rambling post was made at nearly 2am, so if you want to understand more about this stuff, google any of the terms above! Short story, don’t drive in 4wd on dry pavement.

 

[justpassinthru]

Totally normal behavior. I bumped mine once when shutting down the truck. Had stuff dangling from my hand when poking the kill switch. But I was lucky enough to feel it when I did it, and feel the cutover just as everything was shutting down.

More often, like most other folks, I've been in full 4WD in a field and forget to kick it off as I pull out onto a paved road.