I have a 1982 cat d7g serial #92v, my question, should you be able to power through brakes in 1st gear at high idle, I think the trans may be slipping. I ck trans pump pressure and reading 400 plus at high idle, trans fluid full
Yes. The brakes will hold against the transmission in 2nd & 3rd speed with the engine at High Idle RPM, but not in 1st speed.