Today I locked up my rear brakes thanks to a nice lady that turned in front of me. I was going 60mph & when they locked, only the driver side left skid marks & nothing on the passenger side. I checked air pressure and all 8 were the same. So, do I have a canister going out or already out or what? Never locked the brakes up in this truck, but I don't think that is normal.
did you check stroke on each? If you have a restriction or longer hose on one side it can cause those brakes to come on just a little later. This is called "brake balance" in case you want to search for it.
Make sure all the breaks are adjusted right.
you need to lay under the truck and have someone apply the brakes. The rod that comes out of the chamber is where you do your measuring. If it is a type 30 chamber, which it probably is, then from when the brakes are relaxed to when they are applied, the distance has to be less than 2". That's where you have to start. Bad cam bushings can cause this problem along with miss matched hoses. Miss matched brake shoes could be another problem. FWD
Measure drum diameter as well. I have seen new drums that were out of spec still in the box.
Thanks for all the helpful things to check. Wish has a heated shop at work for this type of stuff, especially this time of year.