Flat towing, engine off, p/s fluid question

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Nad_Yvalhosert

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I permanently mounted a tow bar on my old '88 K1500. It's not licensed and I've got some stuff to fix, namely the leaking power steerimg.

What happens to power steering fluid when the engine isn't running and I'm flat towing it?
Does it just stay in the p/s pump and bypass internally? I never seem to need to do a p/s bleed of any internal air after towing it...
 

Komet

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Uhhh, it just sits there. Like the other fluids, they're all just hanging out when the engine isn't spinning.

Is this a trick question? I feel like I'm missing something.
 

GoToGuy

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Is this a quiz? Engine off, pwr steer pump zero rpm. Where is the problem? R & R your bad pump , or lines if faulty. OR ?

How do unpowered wheels turning affect a hydraulic pump who only assists moving a gear driven rod through 100 ° arc back and fourth?
More importantly when you tow this vehicle how are you protecting the drivetrain, trans auto or manual, and transfer case?
 

TreeGeared

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Typically for flat towing you put the transfer case in neutral. That should keep the trans and engine isolated. Transfer case has its own fluid bath and should not matter if it is spinning under power or from rolling wheels. As for the power steering pump I agree with the above comments.
 

DerekTheGreat

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Well, I think the OP is referring to what happens to the fluid when you turn the wheel without the engine running. From what I've seen, if the reservoir is overfilled (and sometimes even if it isn't) turning the wheel to lock or lock-to lock without the engine running is a great way to make a mess inside the engine bay- sprays the stuff through the vent hole everywhere.
 

Nad_Yvalhosert

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Well, I think the OP is referring to what happens to the fluid when you turn the wheel without the engine running. From what I've seen, if the reservoir is overfilled (and sometimes even if it isn't) turning the wheel to lock or lock-to lock without the engine running is a great way to make a mess inside the engine bay- sprays the stuff through the vent hole everywhere.

That's it in a nutshell. My thinking is either it does that, or nothing happens. I wanted to alleviate an unexpected repair, if i could
 

Nad_Yvalhosert

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More importantly when you tow this vehicle how are you protecting the drivetrain, trans auto or manual, and transfer case?

Manual lever t-case in neutral, auto trans in park, key on enough to unlock the steering, battery has a shut off switch.
 
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Pinger

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That's it in a nutshell. My thinking is either it does that, or nothing happens. I wanted to alleviate an unexpected repair, if i could
Raise the front wheels and turn lock to lock and see what happens?
If it looks like it will overflow the reservoir, pull some fluid out and replace when towing is finished.
 

Supercharged111

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I flat towed my Crown Victoria from MI to SD and from there to CA. Never had any issues, so I wouldn't expect you to either. I have seen where fluid moves around in the reservoir if you turn the wheels yourself with the car in the air, as mentioned above. Seems to me this would be emptying out the steering box? But you see geezers flat towing **** boxes behind their RVs all the time, so again, not an issue.
 

PlayingWithTBI

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But you see geezers flat towing **** boxes behind their RVs all the time, so again, not an issue.
As far as the trans goes, I checked that out with our 2015 Ford Escape. They say you can tow it for up to 400 miles before you have to start it up and drive around a little. They also sell a kit where you can disconnect the driveshaft from the trans internally.
 
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