Engine/Transmission (1998.5 - 2002) Power steering fluid leak

[IAdie]

The other day I had power steering fluid all over the driveway. The funny thing was that this must of happened over night without the truck having been run. I checked the fluid level and it was right to the top of the pump as if it had been overfilled, but when I started the truck the fluid level went down and everything appeared to be fine. I did notice that when I first started it when I applied the brakes the steering felt really tight. I had a similar problem to this about a year ago. My wife pulled the truck out the driveway and there was no brakes or steering and power steering fluid was all over the place. We had the truck towed to the dealer, they checked it out and said there was nothing wrong with it. That was when it was under warranty. Now the dealer wants to charge me for this to be checked out again. the truck is a 2002 250 with 40,000 miles on it. I wonder has anyone had simmilar problems.

 

[isb360]

These trucks have something called "Hydro-boost" which is an elaborate hydraulic circuit running from PS pump to power brake booster. Hydraulic pressure from PS pump is used to boost brakes. There is also a small accumulator in the line of the brake circuit so in the event of loss of PS pressure (fluid), you can still stop the truck. There is a good diagram of it in the Factory Service Manual. I believe there is residual pressure in the line(s) after you shut the truck off (same way you can still sort of brake a car when power is off for one or two pumps of the pedal), so that might explain mysterious fluid leakage overnight.



One downside to Hydroboost is that not only does it work the fluid more when you steer, but also when you brake, so any leak is exacerbated by either action and it's hard to drive without steering or braking...



My guess is that one of the hoses has rusted to pieces where rubber crimps into the metal fitting... as happened in my case. Check all hoses carefully to see which ones might be leaking.



One of mine blew down by where it went from PS pump to Hydro-boost booster.



Make sure you know which hose it is because there are four of them, not two.



Tim