I have a 2000 7.3 that blew a high pressure power steering line a month ago so I went to auto zone and bought two new high pressure lines and replaced them after replacing them I started having brake problems while driving straight when you hit the brakes they pulse and don’t have much stopping power but while turning the steering wheel and hit them they work properly so I blamed the pump and put 3 different ones on and also replaced the hydro booster and still no fix I have no idea what else to do

 

Did you bleed all the air out of the power steering/hydroboost system after replacing the hoses? Did you use ATF and not power steering fluid?

 

ATF Fluid goesin the PS pump (Merc V?).... not Power Steering Fluid is a very good suggestion to look at. There is a 'how to' on how to change the fluid out to new fluid.

Also, when 'I' had a 'pulsing' issue... it was one of the brake calipers that was stuck out and pulsing on the rotor. Check your brake calipers for sticking out due to rubber going bad..

imo, you changed some parts that you may not have needed to.

 

Yeah I’ve used all atf and bled everything really good everything worked perfect before I replaced the hoses

 

Does it look or sound like this?

 

No fair teasing.......... What was it?????

 

Air in the hydro-boost/power steering system. It only presented itself months after swapping out the steering gear (replacing the gear you helped me replace at the campground, thanks again Paul!) and the temperatures dropped into the 20's for 3 days in a row. The months prior with typical north GA weather there was no issue or symptoms at all. Once the temperature dropped a bit, the problem was immediately obvious. I did perform a proper and good flush of the system after installing the steering gear, but there must have been some air trapped in there somewhere.

I troubleshot the problem all day and before giving up to purchase a new hydro-boost, I said lets put some ATF through it just to be sure. I looked at everything from the VSS sensor to the ABS module. About 3/4 through the gallon of Valvoline synthetic ATF being flushed in, the pulsing slowed and then eventually stopped. My wife was in the driver seat pushing and letting up and she to this day says she has "magic foots". That was a term we coined as we were happy that the problem went away and for the cost of only a few dollars.

The issue has not presented itself again.

 

You just may have pointed out what happened and may not have known it. One of the connections may have leaked/pulled air into the system and the air needed to be purged. I just replaced in the last few days the high pressure line coming out of the power steering pump and to the Hydro-boost and the line from the Hydro-boost to the steering gear. At each connection, the connections/lines are NOT locked into place snug. Each line connection will allow the line to move slightly back and forth as 'needed' (or if needed). I noticed this when I was tightening the line to the top of the steering gear box. I, could not and it would not 'lock down' the 'line' solid snug/tight. I 'tested' each of the two place where each of the two lines that I had installed at. I could 'move' each line even thought each connection 'nut' was extremely tightened. I would not want anyone to 'test' their lines to see if you could 'move them' by hand, you may 'break' the 'seal' and the connection may leak fluid in one direction and air in the other.

 

I’ve bled the system 50 times I wonder if there is still air trapped some how

 

How did/do you 'bleed' the system, as it is an 'open' system and should bleed itself by moving the steering wheel back and forth?
Let us start back when you 'blew' a high pressure hose line. and replaced two lines. Which line blew (one)? and which lines did you replace (two)?

 

Could be, but not sure really... Where are you located, is it starting to get cold there? Are your symptoms similar to what you saw in my video linked above?

I followed the video instructions I linked below each time I bled the system, including the time after replacing the steering gear and everything being good for months, until the temperature dropped.

Here is the link to my thread where I was troubleshooting and working through the problem before trying to bleed the system, yet again... https://www.ford-trucks.com/forums/1...ide-fixed.html

 

I blew the line from the pump to the booster I’ve tried bleeding it by jacking the front end up and turning the wheel and also by cracking all the lines it was warm when all this started. I know it takes atf fluid but should I try a certain kind I’ve flushed the system and everything

 

The 'power steering system' (of hoses) is deemed an 'open' system. If any air is in the hose system, the air should end up at the pump and be purged out at the pump through normal operation. A 'closed' system would be the brake line system, air is pushed out at the end of each brake line by pumping up the brakes and pushing any air out at the wheel zert. Stop 'cracking' any of the lines open. The 'sealing' of the connection nut(s) collar on the tube may not be any good any more on some or one of the fluid lines and sucking air into the system at one of the line connections. It may be now that all of the lines and the hydro-boost or pump that need to be replaced.

 

Was the engine running and the pump spinning when you did this?

 

okay but why does it work fine when your turning the steering wheel it only acts funky when you driving straight and hit the brakes?