[indosi1]

I have a 2009 silverado 1500 4x4 93k miles 4.8 v8. When I come from a stopped position and start to increase speed, the brakes will gradually engage until completely locked and truck wont move. Shut the truck off 5 min and FIXED until 2 miles down the road and i go to stop and pedal goes to floor "no brakes" release foot and pump break lightly and gradually comes back! Hooked up to scan tool at mechanics and had codes for data link com errors and canbus com error along with some other misc B.S. codes!
ANY IDEAS!
Thanks Ian

 

[GR2017]

If the brakes are being applied without the pedal being pushed, I would be looking at the function of the ABS unit. It, of course, has a pump to apply braking electronically.

 

[Rambodog]

If a caliper is not releasing it will build up heat and eventually lock up the wheel by expansion of the pads due to heat. Once cooled it can be driven a short distance till it heats again. As brakes heat and fade, the pedal goes further to do the same job till it locks up. You may have other issues. but the locking is due to over heating. Sounds like you have some brake work ahead either way. Start diagnostics with the wheel that is hottest to the touch when things lock up.