My uncle truck cruise control quit working on his 2003. Set at 65.then drop.then go back up. Now it don't work anymore

 

There is a vacuum pump between the battery and firewall{passenger side} also a black plastic tube that crosses over to the center of the firewall, that supplies vacuum to cruise control, this tube cracks and with that goes cruise ;;;

 

Tell your uncle to look at the cruise servo i think it is. Its under the driver side fender. You need to remove the wheel arch to get to it. 3 small bolts hold it on. It has a wire that goes to the the throttle on the side of the intake (Where the apps is located) i had to replace mine.

Same issue as you had. I got a second hand one from ebay just to try. They are the same as on a Jeep Liberty i believe, youjust need the bracket from the truck swapped onto it.
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