Hydraulics Question, End dump pushing fluid out of upper tank

I currently drive an end dump that delivers coal fines.
Our company has two end dump trailers and both have the same problem.

The blade will push out the load, but if we pull the blade all the way back in, hydraulic fluid will gush out
of the upper tank.

Now, we've managed to get around this by pulling the blade back half way after a load is pushed out.
And then when I get back to the mine, before I am loaded again, I pull the blade back all the way.

Everyone says that the problem the hydraulic system is having, is that it comes back into the system much slower than going out. Hope that made sense. I am not a mechanic and I haven't drove these types of trucks for very long.

As to the fix, no one knows and the mechanic doesn't know either. He also doesn't want to want to figure out what the problem is or he already would have.

Any of you know what is going on?

 

Yeah, we've been doing that. After I push the load out, I bring it back halfway then when I am ready for my 2nd load of the day, I bring all the way back in.

Everyone at my company, mechanics, drivers etc, all say the same thing
"It shouldn't be doing that."

And about the air, I don't know about that. But I do know it's not overfilled.
Because, it did this over and over, until I didn't have enough hydraulic fluid to pull the load back in.


I like this company I am working, it's great money, with no insurance, very mom and pop--good people but dmn, we are asked to fix a lot of things that mechanics would generally fix. And while their trucks are good, the end dump trailers gotta be 25 yrs old and are constantly having issues.

It takes me 30 mins OR MORE to dump a load.
THese guys with the side dumps..ha, it takes them 3.
I mean, I get there before anyone else, leave before anyone else and they will still catch me and beat me back to the yard--and yeah, have shorter days than I do.



Thank you