About 2 1/2 years ago I had the auto transmission rebuilt and it's been working fine. This winter after running in 4WD a few times and dropping back into 2WD the 4WD light continues to light and flashes on/off kind of at the rate at which my speed increases/decreases and occasionally will stay on.

Has anyone experienced or heard about this behaviour. I'm about ready to take it to the shop but since the warranty has expired I thought I'd see if there was a known remedy (other than replacing it with a manual).

Thanks,
Coz

 

The 4wheel indicator light is controled by a sensor on the vacum solinoid that engages your axle. The light flashing intermitantly likely means that either the vacum supply to the solinoid is not constant, or that the diaphram has failed in the solinoid,or possibly the sensor. Check the vacum lines to the solinoid which is located on the passenger side of your front axle. If that is not the cause, then you will likely have to replace the vacum solinoid. This is one of the long list of common problems with these 'trucks'.

 

Thanks fulltrack!

I'll check that out. Hopefully it won't be anything more serious than that.

 

I had this same thing happen to me. Turned out that the vacuum line that runs along the passenger frame rail next to the exhaust had gotten a tiny hole burned into it by the heat of the exhaust. I replaced that section of vacuum line, and that fixed my problem.
FYI, another symptom of a vacuum problem in this area is that your heater and air conditioning blower will switch to defrost when you are on the throttle or under load (like going up a hill).