Rehab and filter oils for testing?

[ballchinny]

Curious if you guys have any resources or data on more practical filtration of oils for reuse in a temporary test application? We have a large dozer that got coolant in the trans to a large degree. It sat for quite a while so the majority of coolant was able to be drained off the bottom, but it obvious affected the oil and the viscosity of oil is thick, and is playing hell with filters and pressure readings.

We would just change the oil but there is indication we may need to tear into the trans anyway so it is like throwing money out the window. I'd just like to get the oil viscosity in the window for tests. We are not talking about stress tests, just ensure we have mobility. Obviously we could go to extremes to clean the oil, but I am curious about any reasonable approaches? I had the thought to just cut the oil with diesel as it might do some good to clean the trans parts a bit, but elsewhere I was cussed out for that. I feel I have some valid reasons in that approach but I digress.

 

[kschachn]

What are you asking? I'm reading "reuse" but then you go on to talk about coolant and transmission fluid. Plus you're throwing in something about the grade of the oil you're using. Also something about filters...

Why on earth would you "cut the oil with diesel"? There is no valid reason for that when multiple grades are available.

 

[wwillson]

Transmissions and hydraulic systems in a dozer are very expensive. Did you fix the reason coolant is getting into the hydraulic fluid? Why would you think the trans may need to be overhauled? What tests are you trying to run? What is getting in the filters?

 

[Kira]

Reads like you're on a budget. Are you resurrecting a dormant beast?

The way I read it you want to use diesel diluted TRANSMISSION oil in an effort to (I assume) rid the transmission of the coolant and possibly clean the parts.
You must fix your leaking part(s) first. The TME (Time, Money and Effort) involved will dwarf the cost of just using new lube.

Can you isolate the cooler so it no longer sends coolant to its cooling loop (again, I assume it's in the radiator).

Also, from what you said, it appears your "temporary test application" is to see if this dozer will go into gear and move against resistance, yes.

Also, I see this is your first post and even though I'm not on the welcoming committee, WELCOME.
Do try to organize your thoughts. You can also provide details on the vehicle/machinery/whatever you're working on.

 

[dnewton3]

OP - welcome to the site!

I think what you're after (the magic solution that is incredibly effective, very inexpensive, and highly probable to succeed) simply does not exist.

You essentially have a couple of options:
- safe route: bite the bullet and do the teardown
- quick route: change the fluid with PROPER spec trans fluid, along with filters, multiple times until the entire trans "cleans up". This will likely take at least three Oil and Filter changes, with very short run cycles in-between. This is essentially a "flush out the garbage" approach. As you mentioned, this is likley not cheap due to volume of fluids needed, but it is way cheaper than the "safe route" option, but ONLY if the "quick route" works.

Simply put, you cannot get to have your cake and eat it too. There's going to be some risk of wasting money one way or another. If you take the safe route, and the quick route would have worked, then you waste time and money on expenses which were avoidable. However, if you take the quick route and it fails to give adequate relief, then it was wasted time/money throwing money down the hole for nothing. It's obvious you get that, or you'd not be here asking these questions. What you're probably unprepared to accept is that you don't get to have it both ways. So, just pick a direction and just realize that you have no way of knowing until you arrive at the destination, if you made the right choice or not.

Either way, you gotta fix the leak, so don't do anything until that's addressed first.

 

[ballchinny]

Hi guys. I guess I try to exclude certain info in a post so it doesn't wander too much but I bought the dozer not running. Prev owner spent tons on it putting new parts into it and 60 days later was not getting proper oil pressure to trans clutches. Dealer takes it to a field and beats on it for 2 hours, breaks it, then tells the customer to pay up. I bought it with no promises of anything, but I am stepping through it like a chess game. I can tell you I don't have even one of the many filters in the trans system with metal in it.

Dealer never indicated coolant got in the trans. They either missed it or covered it up. So I just didn't know! If you pull a dipstick, you won't see coolant, especially after sittings. The oil is total garbage and viscosity is high. It's supposed to be SAE30. Some of the crap on the filters is like sludge, not oil.

Despite what some may think, I am not haphazardly stepping through the machine. Took 2 weeks before I did another test fire on it with gauges all over the place. I am getting good trans pressure from the trans pump but all that oil goes through pressure filters and after those filters it is pathetic.

Yes, cooler is fixed.

What I am fighting right now is the input shaft on the trans is 100% locked. Some seem to think "it's a frozen bearing" but we are talking insane torque here and I have not seen hardly any rust in that trans yet. It's entirely possible the dealer ran this thing and cooked it off good, but what I need to do right now is somehow verify my trans clutch packs are disengaging because trans pressure locks them, but return springs should return them. I think some trans pistons are a bit stuck.

All I am doing right now is going through a checklist before I decide to remove trans. It is possible, yet unlikely I will be able to free the trans and have any confidence in it. There are a lot of variables and one of them is it would be super to actually get proper oil pressures throughout the trans system before I open it so I know pressures are good and something mechanical is at fault.

 

[dnewton3]

I must confess outwardly that these types of trannies are not familiar to me. I've not worked on one or seen one apart. Would love to see such, but just hasn't crossed my path.

That said, it just seems to me, given your descriptions and details, that a teardown is warranted. If the oil turned to milkshake, then was changed out prior to your purchase, that's deceitful, but likley going to be hard for you to prove. Even if that is the case, it would then have to have seized up; high viscosity isn't going to create the conditions you describe by pumping restriction alone, IMO.

 

[ballchinny]

There really was no smoke screen here. The full "buyer beware" disclosure was upfront. It was a hope that they missed something but that is not the case. Good news is there is no metal detected on any screens or filters so i am hoping it is repairable. I bought it cheap enough that I can spend a bit to try.

These transmissions are not overly complex, but they are extremely heavy, with lots of parts. Even if I were able to free the transmission from the bind it is in, it might fail in short order and that same oil feeds many other things, like the torque converter that was just replaced.

 

[kschachn]

There really was no smoke screen here. The full "buyer beware" disclosure was upfront. It was a hope that they missed something but that is not the case. Good news is there is no metal detected on any screens or filters so i am hoping it is repairable. I bought it cheap enough that I can spend a bit to try.

These transmissions are not overly complex, but they are extremely heavy, with lots of parts. Even if I were able to free the transmission from the bind it is in, it might fail in short order and that same oil feeds many other things, like the torque converter that was just replaced.

I'd love to see some pictures of this beast.

 

[ballchinny]

I'd love to see some pictures of this beast.

Well, there's 56K lbs of it, what do you want to see? lol The trans weighs about 4K. Nothing that the 55K lb excavator won't manage like flea, but getting to that point will be less than exciting....at least for me.

the question I have at the moment is what turned this 30W oil nearly black! That is not normal, and I know the oil was changed only 60 days prior to this failure. There was an oil analysis pulled back then. I might see if I can get lucky and snag that.