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For those of you that have done the hydroboost conversion, what kind of fluid are you running?
I did the complete swap from a 91 superduty, and put in some ATF, and it's pretty whiney when it gets a load on the system. I can see I have to flush it out, and figured I would see what everyone runs for fluid in there's. Hoping to get rid of the whine.
Everything worked good with no noise when it was installed in the superduty.
Woah I didn't know that, so you're saying the old ford thompson "pencil neck" pumps should use ATF? I have a pencil neck pump on a 390 that is pumping to a '79 4wd steering gear and it does whine quite a bit! What kind of ATF?
For those of you that have done the hydroboost conversion, what kind of fluid are you running?
I did the complete swap from a 91 superduty, and put in some ATF, and it's pretty whiney when it gets a load on the system. I can see I have to flush it out, and figured I would see what everyone runs for fluid in there's. Hoping to get rid of the whine.
Everything worked good with no noise when it was installed in the superduty.
If you are using a complete 91 SD system ask over there what they use.
I can tell you 86 GM diesel with hydro boot use power steering fluid but cant say what a 91 SD uses.
As for the round body Ford pumps I have heard they make noise and why on the later 80's trucks / vans use the GM style pump.
I converted my 81 F100 to the GM style pump.
Dave ----
I just did the Hydroboost conversion a couple of months ago. Got the complete kit from Wild Horses 4x4 for my 77 F150 4x4.
They use and recommend Swepco 715. So I cleaned out my system the best I could and switched it over.
I rebuilt a spare Saginaw pump I had for my 73 Formula Firebird. Picked up a new dual return reservoir from a place in MN.
Even if you used GM or ATF transmission fluid I don’t see that being a problem/issue at all.
If you got the whine in the system and the steering or braking is funny then you got air in the system and you need to bleed the system. Also check all of your hose connections or any leaks. That can be a source of your problem as well.
If you've got a rebuild pump and clean hydroboost system, you can use any type of fluid you want really.
I rebuilt my 2001 Superduty CII pump with a rebuild kit, cleaned everything thoroughly, and cleaned out the power steering box (1979 F250 original box), and everything works perfectly with Mercon V. No leaks. No whining, unless at full lock... but full lock whine is to be expected.
As long as you've got a clean system to start with, pick a fluid and go with it Mixing two types is where things go wrong (Type F and Mercon V don't mix).