life_is_an_open_road wrote:
Thanks to all those who provided input on this one-time (hopefully!) braking issue.
I just got the truck back from the shop where a full four wheel brake inspection was performed. The technician found that the front driver side rotor was discolored so it had indeed seen some excessive heat. That being said, it wasn’t warped, the calipers weren’t sticking or grooved and there was no rust present. The pads are 40% worn so with over half their life left it didn’t seem appropriate to change them. (The mechanic concurred.) They witnessed nothing wrong with the hydraulic lines or any of the hoses. The brakes on the other wheels were similarly given a clean bill of health. The tech took the truck for a spin and did several hard applications of the brakes. He couldn’t get the brakes to lock up and the shop’s thermal probe indicated no out of the ordinary rotor temperatures – of course all this testing is being done without the truck being hitched to my trailer.
Get another mechanic.
That rotor overheated for a REASON.
You either have THREE OTHER brakes NOT WORKING as well as they should or the driverside front brake IS sticking (or not relaxing enough).
You can not physically observe a collapsed hose from the OUTSIDE. This IS a known problem, the hose is comprised of SEVERAL LAYERS and it is well known that the INTERNAL layer can collapse without any noticeable indication on the outside.
If the hose has collapsed on the inside it will allow brake fluid to be pushed from the MC into the wheel cylinder when you brake hard enough. But when you let up on the brakes there is not enough pressure in the brake cylinders to push the fluid out and back into the MC (brakes pads need to relax and a collapsed hose does not allow for that).
You have a '09 model year, and I would be willing to bet that the mechanic did not remove the brake pads and INSPECT the ends of the pads which SLIDE inside the calipers. There is a spring on both sides of the pad inside the caliper grooves which RUSTS. This spring also tend to collect MUD and DIRT. If there is any mud, dirt, rust in that area the pads WILL seize.
Our '06 I HAD TO HAMMER the brake pads out of the calipers, they were that stuck. You can not physically inspect the grooves/springs/ ends of the pads without removing the pads..
The brake pads from the factory (and even aftermarket) FIT the grooves way too tight and it does not take much rust or dirt to prevent the pads from sliding in the calipers.
Refitting the pads by filing or grinding some material off the pads where they fit the caliper grooves to make them slide easily is a cheap and easy fix.
The signs of that one brake overheating should be cause for concern and it is not related to the trailer..
