Been reading a lot of threads about 4-wheel drive problems. Haven't found a solution for my problem so I thought I would post a thread for some feedback.

97 F-150, 4.6L, 4x4, manual shift.

My problem surfaced about a week ago. While driving normally in 2wd, a loud grinding noise came from what sounded like the front axle. I slowed to a stop and just before I stopped I heard a loud clunk and the noise went away. I limped home hearing the noise several more times before I made it.

Tested everything I could including 4wd operation on jack stands, vacuum solenoids (on the bench), and lube levels in xfer case, linkages, and both differentials. Noise stopped for a while but the 4x4 dash indicator stayed illuminated whether the xfer case was in 4wd or not. Today the grinding noise returned as I was pulling my boat back from a fishing trip. The grinding disappeared as before when I slowed down but I noticed something I handn't noticed before, a clicking noise in what sounded like the right side of the dash (firewall mounted solenoids maybe?). Each time the click happened, the grinding returned. Click again, grinding stopped.

Any ideas?

 

Sounds similar to a problem I am currently having. My situation is a bit different in that I can't get my truck into 4x4 at all. I am thinking it may be an issue with the GEM or a relay as the vacuum does not change (vacuum to front diapharm actuator is always on the same line) when I move the lever into 4x4 (MSOF also). The 97's are prone to water leaking through seams near the windshield and screwing up the GEM.

If you haven't replaced your solenoids, they are prone to water screwing them up (both mine were toast in a 1997 as well). Water had gotten into mine and frozen which cracked them.

I will re-post if I figure out what my issue is.

 

Thanks for the post. I'll keep troubleshooting and let you know if determine the cause of my problem.

 

My problem ended up being a transmission sensor switch that was bad. The part was 7E440 on the ford diagram of the transfer case. It was $20 bucks at ford. There is a small ball on the end that might be sticking which is keeping you in 4WD.

If you search on google, REVYTRUCKS and JACKPINER (I think these are the right names) have a really good post on troubleshooting and replacing this part. It is a bit of a pain to get to and I had to use and crowsfoot wrench end on my ratchet. There is also some teflon tape on the new part, so if you pull out and find yours is good, make sure you put new tape on the sensor to seal - good luck - let us know if you have had any luck.