F-150 4X4 issue…

2003′ F-150 with the 4X4 switch on the dash. Truck has 34K miles on it so a bit surprised this is happening so soon but here is the issue. I had a friend diagnose the issue as the “Engagement Fork” inside the differential needs a new “Fork Control Kit” (Part #F75Z-3N139). He cannot do the job so I’m looking for someone I can trust in the East metro that can do the job. Any idea on how much $ this would be is also appreciated. Thanks guys…RR

Gosh I would think something like that should be covered under the warranty from Ford right?

Keep in mind it is a 2003. I bought a year ago used when it had 22K on it. I gotta’ think the warranty doesn’t go out 10 years correct? RR

Can you tell us a bit more about what is happening? I had an 04 that was trying to engage and they are know to have bad selonoids. If the vacuum is weak the 4×4 will try to engage. Cheap and easy fix. May not be what is going on with yours but figured id mention it.

When driving (or at a stand still…) when I switch the switch to 4X4 high it just doesn’t engage. The 4X4 light lights up on the dash but it doesn’t engage. My friend is a mechanic and says “everything is happening correctly until the forks try to engage in the front differential” so it is his opinion that the forks are worn inside the differential that lock it into 4 wheel drive. This past weekend 75% of the time I could not get it to engage but a few different times it did work if that helps…Thanks 85Lund…

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Can you tell us a bit more about what is happening? I had an 04 that was trying to engage and they are know to have bad selonoids. If the vacuum is weak the 4×4 will try to engage. Cheap and easy fix. May not be what is going on with yours but figured id mention it.

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2003 and older have a different 4×4 system.

I would be surprised if it was an issue with the fork with that many miles, I would guess it to be the vacuum diaphram has a leak from lack of use or the shaft is corroded and needs to be lubed….hard to tell over the internet. It would be best to have the person that looked at it fix it, all the mechanics that I know will diagnose the issue themselves prior to repair.

Just had mine replaced at ford dealer in my 2006 f150 cost me $280.

It is hard on our vehicles to sit around and not be driven for that long. Mine sat for a year and I had to fix lots of little things here and there.

Bring it to another place and get them to check to see if that is the problem. They may have encountered the same issue before. I know my 01 had issues right after I bought it with 30k on it and I just kept driving and kept using the 4wd and it worked better and never replaced parts for it. Use it or lose it when it comes to 4wd.

Ariat, There is no shift fork in your front axle to replace, that was eliminated in 04. Sounds more like you had the actuator motor replaced on your T-case for that price.

Check the vacuum!!! Easy fix! Sounds like what happened to me.

Had a local rural garage do mine a month ago. The fork kit was $200, labor was $125. Very common problem. The front diff has to come out.

X2 on the vacuume check!! MOST of the time internals being “worn” are from use. Meaning high mileage. Low miles with on an old truck would make me think it’s an external part like a vacuume line or a dried out diaphragm. Just a guess though.

X3 on vacuum. 98 Ranger that would not engage. Dash light came on, you could here it make a noise but no power to front wheels. Ford garage found several cracked lines, replaced them and now good as new. &150.00 lines and labor.