More boring T-Case stuff

[Ernzo]

I think I figured it out, a NP229 does not want to run in 4 with the front axles disconected. As such, when you move the lever, the axels connect/disconnect first, then the case goes back into 2or into 4 via a vacume line.

If you move the select-trak lever and the axle disconnects, but the case does not, I believe the VC goes haywire trying to figure out the torque, since there is no resistence from the front.

Does this sound close? I am fairly sure that is what happened to me. If so, then can isolate it to the vacume motor/lines etc. and make sure that they are repaired and/or replaced. I will replace all the lines anyway.

[ August 24, 2002, 10:53 AM: Message edited by: Ernzo ]

[joe]

I would think if the axle disconnects and the x-case doesn't shift back to 2WD it would be just like running with the hubs unlocked and in 4WD...it'd run till the VC burnt up. I'll email ya couple of pics that may or may not help.
You are correct though when you switch the selector switch either way, the vac goes to the axle first then to the x-case.

[Bob Barry]

I think they designed the front-axle disconnect so that it wouldn't allow vacuum to reach the transfer-case vacuum shift motor until the front axle was absolutely connected. That was the safety-feature for that viscous coupler.

Of course, in the intervening 18 years, a lot could happen, but it wouldn't drive normally if the front axle was disconnected and you were in 4Hi. It would feel like the transmission was slipping horribly, so hopefully you'd stop driving to see what was the matter.

[Ernzo]

Hey Bob,

Well, sadly, it did cause it to slip, but not all the time! I mean, I would shift from 4 to 2 and go forward a few feet, then backwards to ensure that all was 'shifted', then drive off. Sometime later I would feel the slippage. Like you said a horrible slippage! I would then realize that it was in between!! I would again try the selectrak lever, go back and forth etc, but while I could tell that the axles were disconnected, I could never be sure about the t-case. I simply am guessing at what happened, but I am thinking that the vacume motor on the case and or linkage was not working.