I'm back.

Thanks for all the help in getting my lockup clutch issue resolved.

Unfortunately, for the week or two I drove it in limp home mode with the super hard 1st-2nd upshift between 25 and 30 mph, I think that those super hard shifts finally did in the transfer case.

Since the lockup clutch has been fixed, I have now been hearing/feeling a rumbling/vibration while accelerating up to 34-45mph, which would go away once the beast reached cruising speed.

II know some of you suspected a deteriorating torque plate, but I suspected that maybe it was that weird Hooke joint in the front driveshaft as I had replaced the front driveshaft with one of a donor about 6 months ago.

To determine whether it was the front driveshaft, this evening I decided to remove the front driveshaft to see if the noise/vibration would still be there. When I had replaced the front driveshaft six months ago, I did the same thing and it drove fine without the front shaft. (BTW, the Hooke joint in the new used shaft is now stiff/binding, and not at the U-joints but rather at those internal ball-like joints)

However, this time, with the front driveshaft removed (and therefore no load on the front output shaft), when starting out it first bucked-- (like the limp home mode kind of buck, but at a lower speed, like 5-10mph -- then it lost propulsion (engine would rev put zero forward motion) and made a really loud and rapid clicking sound. When I nursed it back home after the couple hundred yard nightmare, I put it in park and it almost rolled away when I got out, i.e., no park engagement (in most non transfer-case automatic vehicles, the park pin is in the transmission, right, but maybe in the D2 it is in the transfer case?)

I put the front driveshaft back on, and now there is no bucking or loud clicking or no propulsion, but the rumbling under acceleration/variable load is worse than before. And the parking pin appears to engage now as well.

Did I put a stake in the heart of an already dying transfer case?

Responses would be appreciated as I am going to Dallas on Saturday (3+ hours from Austin), and there is an 03-04 transfer case up there I could pick up on the way back if the consensus is that I fried my transfer case.

 

Park lock is in the transmission not the transfer case,unless your is weird. But as I recall if your transfer case is in neutral you can still roll, basically the output shaft's can turn freely. But your description sounds like the transfer case to me, but I would remove the rear drive shaft and see what happens. My suspicion is you will move with less effort, sounds like you have an issue getting power to the rear output shaft. Could be the rear drive shaft bindg but I think that is more of an outlier

 

Richard, pretty sure not a driveshaft issue, but could be rear differential, but given where the vibration/sound appears to emanating from, don't think it is in the back.

Again, the scariest part of the behavior when the front driveshaft was off was there would be this herky-jerky engagement but then "freewheeling": the engine would rev in drive but nothing would happen, i.e. zerp forward motion.

I would guess the torque converter, except when I reinstalled the front driveshaft, no more engine spinning but nothing getting to the wheels (though the noise under load is louder).

 

Sounds like a transfer case issue to me. The clicking is a good indicator... You have tried switching into Low range to see if this still happens, right?

 

nope haven't. Is the gear set for low independent of the high range?