Hello all, been trying to find information on what is in my future with my dozer that does not travel forward. I searched through the forums for my model number and numerous attempts at describing the problem before starting this thread. I purchased the machine about a month ago and have put around 35-40 hours on it clearing trees, and building a road. While pushing dirt (and cutting about 2-3" of fresh earth), there was a pop sound, and the dozer stopped. I still have reverse. I called the local Komatsu dealer and talked with their service tech and his opinion is that there is some failure within the transmission. This is what I was thinking as well but their parts guy wouldn't tell me how much parts were without knowing exactly what was wrong. I can get the forward/3rd clutch pack (individual discs) for around $120 each totaling around $1500 for parts assuming this is the only problem, though I believe there is a gear broken and somehow lodged within this assembly since when attempting to go forward the engine immediately bogs down, traveling in reverse is normal. I have no idea yet how much the gear would be. If the problem has damaged the transmission case, the dealer can get me a new transmission from Japan by the first week of September for $35,000.... Not gonna do that. That's more than the machine is worth! I can get a refurb tranny for $8,500 + $1,500 core... This is an option. An expensive option, but still an option. No word yet on a good used transmission since the salvage yard I called is still looking for one.... I think this is my preferred route if one is available since I am not going to put too many more hours in the machine. So my three questions are as follows: 1.) Was this failure imminent? Or did I push the dozer too far and cause the damage. In the past Either the tracks spin, or the engine bogs down which would tell me that I was pushing too hard. This time, no engine bog (other than what I was used to when pushing dirt) before the failure. I was pushing for around 100' before the failure. 2.) Has anyone experienced a similar failure? Was it able to be repaired without replacing the transmission? How difficult is it to pull this transmission from this model of dozer? 3.) Is there any difference between a D31P-20, and a D31P-20A? I was looking at parts books, but cannot find a book without the "A" in the model number. Thanks in advance! And for anyone needing help with theirs, I have the shop manual and can lend a hand that way... But other technical expertise is non-existant with me since I am totally new to dozer ownership.
We have the same dozer great little machine. Just curious have you drained the transmission fluid I look at the fluid. Sounds like it has a broken gear to me too. I wouldn’t run it that’s fosho especially if it has metal rolling around in there. Good luck
I have not checked the transmission oil for contamination yet. Durn job keeps getting in the way.
Drain the transmission fluid and see what comes out with it. You can use a flexible magnet through the drain hole and attempt to find anything. When a transmission "POPS" and loses a direction, its NEVER good or cheap.
Will do. Any guess on how bad it could be before I tear into this thing? Opinion on if I'm going to need a new transmission, or if some internals may be sufficient? And, if just some internal parts, do I replace all clutch packs while in there, or just damaged/worn components? I am no stranger to working on vehicles, just never equipment like this. Thanks!
Getting a transmission model and serial number will help finding parts outside of the dealer. Your not going to guess the damage and parts needed without a complete tear down. If I wear doing it, I would replace all the bearings and seals, possibly friction discs if they were questionable. I doubt anyone at Kirby Smith could rebuild the transmission, they do more component replacement than rebuilds of their own. Yes, any transmission can be rebuilt. It’s the cost and availability of what you need that will determine if it’s even feasible. You will need a proper repair manual and possible special tooling.
That is encouraging. I do have a shop manual and it goes through quite a few procedures. For parts, do you know if there is any difference in a D31P-20 and a D31P-20A? I was looking at the parts books on ebay, and can't find one without the "A".
I don’t know for sure. I bet JohnC could answer that one for you.