EDB, very glad you got some good news on your medical adventure!!!

On the 7, I did check the trans shift shafts and did not detect any excessive amounts of play. It is possible that is the point of leakage inside the trans but I believe this shifting issue is compounded. When I mentioned it would not go into 3rd, it most certainly did for a brief amount of time and I think what is happening is a loss of oil pressure as soon as trans is put into gear. This is due to both the valves and whatever else leaking oil, and the oil itself which apparently is so bad that it will not flow through the pressure filters. This is evident by the pressure tests that should pump pressure of 200-300, yet pressure just after the filters at 20-30psi. That is even with brand new filters, and one of the previous ones were actually blown! The front one, but I am not sure if the filter system runs the filters in series or parallel? IE, did the blown filter let junk oil into the trans?

If the trans was not locked, I might consider replacing oil for testing, but with the frozen yoke, that is obviously not good. This is why I feel it is worth taking the top of the trans off so I can remove/inspect the valves, and try to operate the trans clutches with compressed air or at least inspect the clutches for free play.

Again, there has been no serious metal found in any filter. Mostly just black slurry that might be from the brakes, but seems obvious that the coolant ruined the oil and now it flows like snot, not oil! It won't even go through a brand new filter!

Hi Bobby1,
yes, remove the top cover and valves and operate the clutches with air pressure using an air nozzle and suitable rubber bung or other with a hole punched in it to suit nozzle tip.
Air pressure at around 100 psi is more than enough to test the clutches for operation--after reassembly at the Dealer we did this exact test before fitting the outer case valves etc. and then testing the said transmission on our Rogers trans./hydraulic test centre before dispatching back to the client.

The common cause of input shaft lockup were broken Fwd or 1st speed planet gears breaking into 3 or more pieces due to rough shifting operation by the operator.
I have seen a couple of actual clutch piston housings split open from the forces generated when inertial forces added to the torque converter output torque.
These bits then jammed in between the planetary ring gear and carrier itself--your experience may vary.

Good Luck with this adventure.
Keep us in the loop for further assistance and situation reports.
Cheers,
Eddie B.

Will do! Right now I am just trying to spot a day with perfect weather to continue my work. I do know if planetaries were damaged, I didn't cause it, and that would go right back at the dealership as it was tested for hours in running condition there.

Correct me if wrong, but I intend to try to slip feelers or something between clutches, or similar methods to determine if clutch packs are free. I am not yet familiar with what all will become visible and accessible one the top is removed so I am trying to plan my attack before hand. Sometimes things stand out instantly, and remedies are obvious. I know in some clutch packs i have visibly seen broken plates which is an obvious teardown. In this matter, I realize loose or otherwise free clutches does not prove everything, but it point more towards serious planetary damage. If I can find tight clutches, it might mean the water has frozen some clutch pistons where I would assume hydraulic compression forces largely outweigh the return spring forces and they may not be able to return the piston correctly.

All guesses at my end, but I realize the more I understand before going in, the better I will be able to diagnose it. I am kind of just hoping for a good confirmation of internal issues so I can fully justify opening it. I am scared at all working on the trans, it is the removal process that I am less than excited about.

I guess while we are on the subject of removal, maybe someone could comment on what needs removed, what can stay, and if we will have clearance to pull trans straight foreward, then straight up? We do have the winch, but in looking at both book pics and identical pics of a winch online, it appears there is a long driveshaft on the winch with a female coupling? So the trans pto would just pull right out of that? Really trying to avoid pulling the winch, but I realize I will probably need to pull the tank and at least center bevel cover to get access to the shaft for alignment, but inspection in that area needs to happen anyway.

Hi Team,
from my 1965 Cat Trans School notes hand out these the scans show the first 2 pages of 10 showing the steps of trans dismantling of this style of trans used in the 3 machines--there are small differences between the 3 but this is close enough to give an idea as the overall design is the same.

As you can see it shows a view looking into the trans with the top cover and valves removed so you air test the clutches in the holes visible in case opening.
Looked for a suggested tooling for air test that I recall seeing somewhere in the distant past but no go as yet.
This all should be in a relevant Service Manual for the machine.
I have included Cat's Troubleshooting Chart that I found to be of little to no help in my 43 years at the Dealer.
Cheers,
Eddie B.

Not to take this thread off topic, but guys will have the attitude that bmr has and then wonder why the hobby is dying. Doesn't sound like ACMOC is the place for him.

sounds like its a "fun" job to dismantle the trans. but it does sound like the issue happened when the dealer was "testing the machine" perhaps they were a bit too rough. yes wear in the controls or things being out of adjustment wouldn't help. who says the previous owner wasn't a butcher and when the workshop went testing it finally let go.

The way that the tech info reads, it sure sounds like the dealer beat the crap out of it. Something along the lines of "ran machine for several hours trying to duplicate customer's concerns. Was able to find problem. Machine was drug back to shop with another dozer. Original complaint was that it would not steer on one side and not shifting correctly.

My guess is the coolant in there did a nice number as the tech continued his "work" and possibly got both FWD and R clutches in and broke it good.

Really all guesses until I get a good clearing to open it up. Really, the time to remove it. I am NOT looking forward to the removal process.