outdoorsavvy85

I have now broken 2 front cv driveshafts within the last 2 months. I have the all time 4wd, 249 tcase and currently I have the driveshaft removed. The first one broke while wheeling but this replacement (from a parts ZJ with 80k miles) broken yesterday after dropping it off for an alignment.

I was told in a FB Group that with my 249 being in a 1996 (96-98) ZJ, that no damage would be done with the driveshaft being removed. Is that accurate and will it still be able to roll with the driveshaft being removed and/or broken?

Thanks in advance!

dave1123

I beg to differ. Your 96 still has the viscous clutch which will overheat without a front shaft. Usually they slip when this happens but it could be locked up causing you to actually be in what's know as Part Time 4wd. This puts immense pressure on the CV joint in the front shaft causing the failures.

If this is the case, I'd be looking at a 242 or 231 swap. Repairing the 249 gets expensive. I'd run without the front shaft until I got parts for the swap.
It will roll in park without the front shaft unless you put it in low range or use the parking brake.

Just my opinion however.

wingless

The NP249 is fine to operate w/ the front driveshaft removed. The empty front yoke spins fully synchronized to the driven rear shaft and the viscous coupler remains happy.

The parking pawl is internal to the rear of the transmission. The transfer case is not like a differential. If the input shaft is locked by the parking pawl, then the rear output shaft will not rotate, even when the front driveshaft is removed.

Replacing the VC is reasonable difficulty and reasonable cost.

outdoorsavvy85

Let's say I did a swap for a better tcase, can I pull a u-joint yoke from another ZJ with the same axle to use on mine? Converting my ZJ to a u-joint shaft on each end of the front driveshaft.

dave1123

Yes, but you can't just bolt it on. It's tension controls the preload on the pinion bearings and must be done properly. It requires precision and experience to do it right. You should check with a driveline shop or a heavy truck repair shop for information.