It's not a dumb question at all. It depends on what kind of 4WD you are
running. Systems designed for "part time" driving lock the front and
rear axles together. When you corner each wheel follows an arc with a
different radius and travels different distances. This means that each
wheel turns at a slightly different speed, which means that the axles
turn at different speeds. If the difference cannot be released by
skidding one (or more) tire the system will bind up -- or break,
depending. The advantage is that on slippery surfaces even if one tire
loses traction the other axle /must/ continue to turn, pulling you out.
You'd have to completely lose traction under the dominant wheel on
each axle to get stuck, since both axles are being driven at the same rate.

"Full time" systems incorporate some sort of differential between the
axles, a system that allows the axles to turn at different rates, the
same way that the differential between two wheels on the same axle
works. This means that you can drive on dry hard surfaces without
risking drive-line bind or failure.


Jeff via CarKB.com wrote:
> Hey i dont want to sound really dumb here but can someone tell me whats bad
> about using 4x4 even on dry roads. I am just wondering what it does to a
> vehical. Thanks
>

 

It's not a dumb question at all. It depends on what kind of 4WD you are
running. Systems designed for "part time" driving lock the front and
rear axles together. When you corner each wheel follows an arc with a
different radius and travels different distances. This means that each
wheel turns at a slightly different speed, which means that the axles
turn at different speeds. If the difference cannot be released by
skidding one (or more) tire the system will bind up -- or break,
depending. The advantage is that on slippery surfaces even if one tire
loses traction the other axle /must/ continue to turn, pulling you out.
You'd have to completely lose traction under the dominant wheel on
each axle to get stuck, since both axles are being driven at the same rate.

"Full time" systems incorporate some sort of differential between the
axles, a system that allows the axles to turn at different rates, the
same way that the differential between two wheels on the same axle
works. This means that you can drive on dry hard surfaces without
risking drive-line bind or failure.


Jeff via CarKB.com wrote:
> Hey i dont want to sound really dumb here but can someone tell me whats bad
> about using 4x4 even on dry roads. I am just wondering what it does to a
> vehical. Thanks
>

 

It's not a dumb question at all. It depends on what kind of 4WD you are
running. Systems designed for "part time" driving lock the front and
rear axles together. When you corner each wheel follows an arc with a
different radius and travels different distances. This means that each
wheel turns at a slightly different speed, which means that the axles
turn at different speeds. If the difference cannot be released by
skidding one (or more) tire the system will bind up -- or break,
depending. The advantage is that on slippery surfaces even if one tire
loses traction the other axle /must/ continue to turn, pulling you out.
You'd have to completely lose traction under the dominant wheel on
each axle to get stuck, since both axles are being driven at the same rate.

"Full time" systems incorporate some sort of differential between the
axles, a system that allows the axles to turn at different rates, the
same way that the differential between two wheels on the same axle
works. This means that you can drive on dry hard surfaces without
risking drive-line bind or failure.


Jeff via CarKB.com wrote:
> Hey i dont want to sound really dumb here but can someone tell me whats bad
> about using 4x4 even on dry roads. I am just wondering what it does to a
> vehical. Thanks
>