Martian

Nooo, not at all, I'm actually very happy about that. Most folks start a new one and throw a link to the old one because if lots of folks resurrect the same thread it'd get super long if the problem never got fixed haha

Greg Schroeder

I'm glad this thread was brought up again years back. I'll bump it again.

Every morning my 4 wheel drive system works until vehicle warms up. After warm up 4 wheel drive lights blink 3 times

My IWE hubs work and hold vacuum, new vacuum lines, new solenoid, new check valves, new relays, fuses good, new transfer case motor

This is the best thread I've found on this which doesn't divert to all the parts I've already replaced so thank you all.

Greg Schroeder

I fixed my 3 light blinking.

I'm now 100% certain of my issue.

It was the PCM

How did I know?

4 wheel drive worked great when the truck was cold in the morning, until the engine bay was hot. Every single day for over 2 months (time I owned the truck, unknown how long before I got it). when not working I could cover the PCM in cellophane and run a hose on it. Bink! works again.

All other parts were found in working and proper condition, including IWE, vacuum hoses, solenoid, selector ****, transfer case motor, check valves, vacuum canister(hidden behind battery)

Remanufactured PCM installed and 4 wheel drive always works, all day, every day regardless of temperature.

Conclusion by my perspective of value is that it was cheaper to buy the PCM than have it diagnosed while throwing money at it with an unknown variable of who was working on it at a service location.

This should be a recall.