av8roc

What's the actual vac pressure you are reading at the hubs? Also have someone rev the engine while you check the pressure to see if it drops indicating a leak somewhere upstream.

dhodges45

I'm getting 21-22 at the hub. I haven't had anyone rev the engine but turning the wheel by hand you can tell its still engaged. The other wheel isn't. If I'm getting the correct pressure at the hub and one side disengages with the same pressure at its hub it seems to me the vacuum system is fine. I took the lines of at all the connections and checks and blew them out with compressed air and they are all clean. If I was losing pressure at RPM wouldn't I only notice the problem at speed? Just seems like its either the half shaft joint or the IWE its self. I have the factory manual and following he troubleshooting guide it points to the IWE.

av8roc

Yeah that sounds like the actuator itself. I'd try changing it on that side. Check out rockauto.com for pricing.. I want to say the part is about $100ish

camothunder

I'm having a very similar problem I've replaced both actuators And still no 4x4 I bypassed the solenoid And the 4x4 worked for a little bit and now nothing my vacuum lines are all working I just don't know what to do

Trio

Reviving a very old thread here, in an effort to keep everything in one place...

Here is my fix:

Symptoms:
4wd not engaging, no 4wd lights on dash (other than during the initial start-up diagnostic self-check)

What I tried:
Replaced the original IWE solenoid on the passenger firewall behind battery with a newer version (with the plastic "hood"). $25 from Advance Auto. Since I am on long term assignment away from home, I changed it out in the parking lot in 15 minutes with just a 10mm wrench. The result? 4Hi and 4Lo each worked exactly one time, then back to no worky, no lights on the dash.

What next:
After hours of further research, and given my lack of a lift or tools, I read quite a few instances where folks with these symptoms crawled under the truck and took a rubber mallet to the actuator motor on the transfer case. Apparently they get sticky when not used frequently. Given my desperation, helplessness due to lack of garage and tools, and that folks were claiming this to be the best "fix" since viagra...I thought why not?

Since I lacked a rubber mallet, I crawled under the truck and whacked the actuator motor on the t-case a few times with the heel of my dress shoe. The result? It worked! 4Hi and 4Lo, back in business!

Well, a small caveat. I drove for several miles (in a straight line of course) to cycle 4wd on and off. It worked 17 out of 20 times. The other 3 times I had to turn the dial back and forth a couple times to get it to work.

So given my short-term success, do I need to plan to replace the actuator motor on the t-case as a preemptive move? Is it on its way out?



P.S. In full disclosure, I have no way of knowing whether 4wd was fully engaged all the way to the wheels. I was on dry pavement, no way to get the front in the air, and therefore no way to test. I can only verify that the lights on the dash worked again, and I could definitely hear the t-case engaging post-fix.

techrep

iTrader: (1)

Yeah.. I would replace the T-case shift motor.. and you could of turned your wheel while in 4WD to see if the IWE's were locked in.. you can feel the front tires grab the pavement..

Trio

Yep, was finally able to test it today. Everything is working normally with the 4wd, everything is engaged properly. And I am wearing my shoes...can't do that with a rubber mallet.

techrep

iTrader: (1)

Nice !