D5H Brakes dragging

Good day,
Hoping someone has advise/experience on a D5H powershift, Ser# 1DD. Last summer owner complained of trans heat & loss of drive. I checked powertrain filter-- completely plugged. Anyways the powertain pump disintegrated, so I replaced the pump, cleaned screen, new oil. Machine worked great.
A few month later, complaint of trans heat... well it turns out it's torque heating, due to the right brake dragging (low oil pressure right side). So I re-sealed the right brake & steering clutch assembly. Didnt really find any seal damage, but they were fairly hard, and I did find some filings I assume came from the original pump failure. Anyways after this I ran the dozer for 6 hours, everything seemed great, delivered machine. Owner runs it for a few days, same issue. Now I haven't checked all pressures to brakes properly because my memory is **** & I cant check SIS on-site, but I do know I have pressure to brakes, around 420 psi if I recall.
I plan to print off the pressure chart & re-check, but I was hoping someone wiser than me might have some advise
Thanks

Did you inspect the brake discs when you tore it down could be coming apart and bunching up but the screen should show brake material in it again if that is the case. test pressure and see if it is lower on that side than the other if it is you have internal leakage

Thanks, I did check the brake discs, they didn’t show any wear which surprised me. I will check pressures later this week & then we’ll know better what’s going on inside. I’m wondering if it is in the valve body

When you replaced trans pump did you clean torque converter screen? Is problem right after initial warm up or 2 to 3 hours into the day

Yup I cleaned torque screen. From what owner says it takes about 3 hours to get the torque hot. But yesterday when I went to check, I noticed as soon as I put it in gear that the brakes were still on. It will drive through the brakes but doesn’t free roll at all.

I would be taking a look at the powertrain cooler myself. If you've had major component failure and a filter in bypass that cooler will most likely need some attention and will definitely be a contributing factor to your heat issue.

Good idea, I noticed the cooler is dirty externally; doesn’t explain why the brakes don’t fully release though.

Check the park brake dump valve for proper adjustment. Check the brake pedal linkage right back to brake valve to make sure it’s releasing.
Also check brake pressure on valve or at brake housing.
When you start it cold and drive it do temp check of the brake final drive housing to see if one side is hotter.

Mobiltech said:

Check the park brake dump valve for proper adjustment. Check the brake pedal linkage right back to brake valve to make sure it’s releasing.
Also check brake pressure on valve or at brake housing.
When you start it cold and drive it do temp check of the brake final drive housing to see if one side is hotter.

Click to expand...

Thanks I will check that