'99 SR5 transfer case question

[shawnstcyr]

:sobbing: My transfer case won't shift into 4WD mode. The last time it did this, it was low on oil. I changed the front and rear output shaft seals. They still leak and are getting worse.

I topped off the oil today. Still won't engage. Does anyone have any suggestions. I have to drive this thing to eastern Co. tomorrow, and I will be so upset if my mountain running weekends are shot. Do these things have bushings that wear out, leading to excessive play and oil leaks? Do they have synchronisers that wear out, not allowing them to shift?

Any suggestions would be helpful.

 

[pat161]

There are syncros in there, perhaps by running it low on oil you wore them out and now it won't engage 4wd.

 

[Burntcreek]

Does the 99 have a light flashing while the 4wd is engaging? If so, is your problem that the light just keeps flashing and doesn't indicate engaged or that you physically can't shift the transfer case into 4hi?

If it's the light flashing, it might be a problem with your ADD not engaging. The light on mine ('02) doesn't indicate engaged until the transfer case has shifted AND the ADD is engaged. This might be different on your '99 but might be worth looking at since there are vacuum lines and VSV's involved.

I just read this good article about the ADD system that was linked in a 5th gen thread:

http://www.off-road.com/trucks4x4/article/articleDetail.jsp?id=399612

I hope it turns out to be an easy fix!