Baystate Jeepers

It's not so much a strength issue as it sometimes could be a handling issue. First, the TJ's 4x4 system is a "part-time" 4x4 system... i.e. it is not designed to be used full-time on the streets. How it works is the transfer case mechanically locks the front & rear driveshafts together and thus the axles are mechanically locked together so they are forced to turn at exactly the same speed/rpm. However, the front axle needs to turn faster during turns since the front tires have to rotate faster than the rear tires do during a turn. Even on a slight highway curve, not just hard 90 degree turns. That causes drivetrain "wind-up" by the front driveshaft trying to rotate faster than the rear driveshaft is and the transfer case is caught in the middle.

That isn't actually known to cause damage, the transfer case is stronger than that. If it wasn't we'd have Wranglers & other trucks found on the side of the road with broken transfer cases from all of the idiots who know no better and like to drive around in 4x4 even when not needed. The real problem is if you get into a varying traction situation, like patches of snow, ice, or even dirt while driving on the highway, that bind (wind-up) could suddenly release itself if one of the tires hits that low traction area and suddenly spins or slips to release the binding/wind-up. That could conceivably cause a spin-out, slide, etc. in some conditions.

The way full-time 4x4 systems or all-wheel drive systems can be driven in 4x4 full-time is that their transfer cases also have a differential inside (like is inside of our axles) that allows for differentiation between the front and rear axles which means wind-up/binding between the axles does not occur.

So the long and the short of it is driving a Wrangler in 4x4 on a high-traction paved surface is not likely to break anything, but it can at least cause compromised handling, jerky steering, etc. from drivetrain wind-up/binding between the front & rear axles. And it certainly isn't good for the transfer case for it to be the center of this binding problem

DuxJeep wrote:Just slid across three lanes in NH on some black ice but recovered before anything bad happened.

My question is does anyone know limitations of driving in 4x4 on hiway? I know there are speed restrictions but with 4” of lift and 37s I don’t want to push the limits and few remaining stock components. Appreciate the feedback!

pirahnah3 wrote:I want to go to Jeffs quote for just a moment on this one....

So lets look at the concept of "wind up" in relation to driving on pavement. Doesnt this happen to the rear axle no matter if the pavement is wet or dry? If they are considering a turn does the rear of the vehicle not also turn? doesnt this then cause the same problem they are trying to avoid having? Im no expert but it just seems like the logic is a bit off to me. I can see it as far as steering goes as that directly effects the front wheels but the science would state that the rear axle does the same thing and would be more likely to skip as you make the turn rather than jerk the wheel.