Hey guys I have a 2014 f150 Stx with 58,600 miles. Was having major issues trying to put in 4x4low, would not engage without doing some grinding then a loud bang in the transfer case. Took it to the dealer yesterday and today they called me and told me they are replacing the transfer case, I thought maybe a bad shift motor. I changed the fluid at 30,000 looked clean with no metal pcs. I only had it in 4x4 low less than 1 mile for the life of the truck. The truck was not beat on, wondering if lack of use of 4x4low hurts the transfer case. I’ve had no problems with this truck in fact it is the first time to the dealer, I do all my own preventative maintenance. 4x4 high no problems. Any others with same problem? Thanks Bob

 

The owners manual does say to operate in 4X4 for 10 miles/month to keep things lubricated. No mention of low range. I doubt that would effect the transfer case though. I've been driving 4X4's since the 1970's and did have a 1991 Jeep Cherokee my wife drove that had issues going into 4X4 after not being used for several months. Nothing broken, just take the front hubs apart, clean, relube, and re assemble. Since then I'm pretty good about using 4X4 regularly and get to low range a few miles a month too. Never had any other problems.

 

Exact same issue with my 13' stx. dealer is correct in replacing t-case. However unless it is being done under warranty I would take it to an independent shop or do it your self. A t-case from a wreaked f150 can be had from LKQ for about 300-400 dollars. I know because I just purchased one. The reason it can go into 4hi no problem is because that is only the chain being engaged by the clutch. The 4lo also engages a gear set that reduces your ratio. I believe it is the splines either not engaging fully that you are hearing grind. It could also be rebuilt.

Here is my forum post b%#$@ing about my 4x4: https://www.f150forum.com/f38/borg-w...4419-a-448599/