Hey guys, I'm a firetruck mechanic in Texas and we have a brush Truck that came in for a leaking steering box. It's a 99 cummins 3500 auto 4x4. We replaced the steering box and went to drive it and the power steering quits working about half way through.
We get it back in the shop thinking the pump was bad so we replaced it and still no good, steering too tight with ought reving the engine. So we replaced all the lines and hydroboost. Finally we replace the gearbox and power steering pump again and still the same problem. What are we doing wrong? Any hints? We've been bleeding it by jacking up the front and turning back and forth. Any help would be greatful, thanks.

 

I never could get all the air out of mine like that. I wound up just driving it for a few days and that got all the air out.

 

Thanks man. Update, yesterday filling put the 4th pump on and everything works fine... can't imagine getting 3 bad pumps brand new, won't be buying any 3f pumps anymore

 

The first 3f pump I put on didn't work at all. The second one is still working fine. It was a chore to change them though and now I run hydralic fluid in it for a little extra pressure. It makes it easier to turn.