TX Tahoe Z71

iTrader: (28)

Welp, that didn't help anything. Hoping switching the T to the return line after the cooler works, otherwise I'm getting a new (junk yard) power steering pump.

TX Tahoe Z71

iTrader: (28)

Switching the T to the line between the cooler and reservoir, with the straight part of the T going from the hydroboost to the reservoir, seemed to have done the trick. No dragging at all and the pedal returns quickly when I let off the brakes.

I did this last night, so time will tell, but usually on cold starts (like this morning at 40*) it's the worst and I have to let it warm up a bit. But this morning, it was ready to go immediately.

Huge thanks for the help guys, I don't think I would have figured this out on my own

Sc00by

Wow!!!!! Just finished my hydroboost conversion (truck in sig) and was having this exact issue. I have a junk yard 2005 2500hd hydroboost and pedal and an autozone ps pump for a 2005 suburban. It comes with the factory low pressure return fitting for the hydroboost. Mine was the factory pump with 275k on it. Brakes were dragging more and more a I drove it. Found this thread and did some research and it turned out I had connected the low pressure hydroboost return into the high pressure ps cooler return on the pump. As the brakes were used the hose would fill up with fluid and back up into the hydroboost causing the brakes to bind up. Swapped the returns around and they now work great. The best mod I have done to my truck. No more white knuckle panic stops! Brakes are much more predictable.

Great thread! Bump to the top! It saved my day!

TrendSetter

Old thread but good info here.
I am having the dragging problem with my 2002 rcsb hydro boost conversion. I did the swap a bunch of years ago and the first time I had the dragging problem I spaced the master out with washers.
The dragging is back.
the truck has been sitting for about 4 weeks. Key on engine off the brakes apply enough I can’t roll the truck in neutral. I loosened the master and can then roll it. Tightened it back up and it seemed that after 15-20 min it wasn’t able to roll again.
I never started the engine so the drain issue seems like it’s not the problem.
I unhooked the pedal from the booster and it has over an inch of upward travel so I don’t think the rod is too long.
Any other ideas? Is it possible the abs unit can cause this?
I haven’t had a lot of time to troubleshoot yet but any brainstorming ahead of time will be helpful.
I don’t remember where the booster came from. Are there any models that have too long of an output rod?
it is mounted upside down but I went many years without trouble and I’m not aware of what changes could have caused the problem to come back.

wardlws

I assume you have the lines run correctly... like in this picture:



If so, you might consider a Y connector instead of a T.

Why do you have the Hydrobooster mounted upside down? I wonder if that might make the rod just a hair too long, or have some binding?

Have you checked your brake pedal return spring to make sure it is mounted correctly and able to hold the pedal up?

TrendSetter

yeah its run right.
turns out i kind of jumped to conclusions and the brake system is ok on the truck.