Hydraulic fluid - Hi-Lo camper travel trailer forum

Morongo111 · 08-01-2023, 04:30 PM

A "friend" put about 1/3 cup of hydraulic fluid 'oil' in my resoviour tank, as it was low. There is a small leak somewhere, to be addressed later. The tank has a very light pink hydraulic fluid in it. Now it is mixed a little. Will this hurt the system, or do I need to drain and refill?

Thanks for any and all input!

JackandJanet · 08-01-2023, 06:06 PM

Depends on what kind of hydraulic fluid he added. If it was Dexron 2, 3 or 4, you're fine. Those are the approved kinds of fluid. If it was Dexron 5 or any other kind of fluid, I'd drain and refill the system, because the seals will be damaged by the non-approved fluid.

To drain and refill, you'll probably need to suck as much out as you can, then refill, doing this about 3 times to get all the bad stuff out.

- Jack

Morongo111 · 08-01-2023, 07:59 PM

my thoughts exactly. thank you so much. i gather, that I will have to put it in the lowest postiion and get a small siphon hose and suck out as much as i can and refill and continue this way, or can i go under and drain lines as well?

JackandJanet · 08-02-2023, 10:35 AM

Yes, that's one way. You should cycle the top up and down between drains to get the undesired fluid mixed/moved out of the system too. It's a bit like a blood exchange.

Another way to drain the system should be to disconnect the return line at the reservoir and put it into a container that will hold the fluid when you lower the top with it disconnected. You SHOULD be able to simply leave it disconnected while you refill the reservoir with the top down and then raise it again to repeat the process. There's no pressure on the return line and nothing should come out of it unless the top is being lowered.

I've found Dexron 3 online and that's what I've put in my trailer.

- Jack

Morongo111 · 08-02-2023, 04:34 PM

THANK YOU SOOOO MUCH! Got my weekend planned, LOL