I have a Tow-Pro™ Elite fitted to my vehicle. I have recently picked up a new van and am having a few issues with the proportional braking on the van. The problem is that the brakes on the van are very unpredictable. When applying the car brakes, the van brakes tend to over-ride and will eventually lock up after multiple braking applications as what happens when reaching built up areas. I am having to feather the brake pedal and decrease the brake pedal pressure in order to stop the van brakes taking over. I have adjusted the remote to attempt to compensate but the brakes on the van end up being either insufficient or over react and lock up. Initial application seems to be OK but the brakes on the van seem to gradually increase regardless of pedal pressure?
What you describe typically indicates a problem in the brake hubs in the van. We recommend you have them serviced/adjusted by a trailer brake specialist.