Hey guys first post. Just bought an 01 f250 psd with esof last week. I believed the 4wd to be working because I can hear it clunk when I turn the switch, also the lights come on. this evening me and a buddy were going to check out our hunting spot, when my rear wheels started spinning I switched on 4hi, light comes on however front wheels don't move. I jumped out and manually locked the hubs and still nothing. tried 4lo, light came on heard a noise but still no front wheels..finally had to go get someone to pull me out...question does the truck need to be rolling in order for the 4wd to engage with the hubs manually locked? after i got it out I drove for a few hundred yards hubs locked and the front wheels seemed to engage. stopped, put it in low and it geared down and again seemed to be working....when I got home I jacked one side up and checked to make sure the hub was engaging, in auto the wheel spun free of the axle, manual it spun with the axle. I turned the truck on and turned it to 4wd while in park, auto hub did not engage, switched to manual, it engaged the axle but still spun freely making it seem like the transfer case wasn't engaged. Granted one front wheel was on the ground, and it never got put in gear...Does this seem like a bad transfer case motor? or does everything need to roll. the owners manual makes it seem like it might have to be rolling.... unfortunately I dont have a lift or jack stands right now to do a full test. I've searched countless threads and from what Ive read it either needed to be rolling or that motor is going bad. I could give a rats *** about the auto hub not seeming to work although I think they are they just need to roll, I would much rather have a manual system but this truck was too good a deal to pass up...

 

the wheels need to turn a little for the splines in the hubs to line up and engage when commanded to lock (via vacuum or manual turn).. so if you're stuck and want to engage 4wd, you'll want your hubs to have already been locked.

and welcome to the site!

 

If you manually locked the hubs and you did not get any power to the front wheels, then your transfer case shift motor isn't shifting into 4H properly. The clunk you hear might be the motor trying to shift the case.

The hubs and transfer case do not need to roll forward or backwards to engage.

There used to be a style of automatic hubs that required a forward or reverse roll to engage (my 1995 F-150 came with them) but they are not used anymore that I know of. They were weak and not real reliable.

 

So Im hearing it could be either issue. Guess ill have to hunt down a lift and see if its working..if it is the motor its not very expensive. $100 on partsgeek.com

 

snce your hubs are still working(able to turn) its not your hubs i say your motor either has a broken gear in it or its dirty from salt rain etc. pull the motor off the t-case and have someone turn the 4x4 dial to 4hi and see if the motor turns if so turn the t-case shaft with your hand and make sure it locks into 4wd. Id also drain the tcase fluid and install Mobil1 synthetic ATF. After i di this my tcase goes in and out butter smooth! Also you have to put the truck in N hold your foot on the brake and then turn the dash switch to 4wd, my dad forgets this all the time and his tcase never goes in, dont forget stop, N, hold foot on brake and turn dial same to go back to 2wd