I have a 2000 f150 5.4. 4x4 automatic with manual 4x4 but it does not have lock in hubs. My four wheel drive will go in someimes. It also feels like the shifting lever in the truck is loose. I replaced a selenoid and was told to replace the gem (body control) module that it could be bad. All vacuum hoses have been checked. I was looking to see if anyone had any help because the gem module is 499 at ford. Hoping it is not that and I hate to buy it if that is not the problem. Any suggrestions on what to check next would be great! Thanks!