Recently bought a d6c - 10k s/n 2041 - posted on here before that it had stopped pulling and had some good advice but after trying several things we have discovered we have a bad powershift transmission so it has to be rebuilt .. The problem we have is it will not move - we had to push it off our construction project with another dozer inches at a time .. I had one fella tell me that with the motor running and the steering clutches pulled out it should roll but it wont . The dozer is sitting in a bad place and we need to pull it approx. 1/4 mile to get it to a good place to pull the tranny - no way to get a truck and trailer to it here either nor would it roll on one anyhow ..... My question is can I make this dozer roll somehow with the transmission locked up ? I notice a large place on the back of this machine - and thinking maybe we might go in there in the rear end and unhook something there that would let this thing roll ??? Also anyone knowing of a good transmission rebuilder in the Arkansas area would be appreciated .. Thanks in advance
Sounds like you have no oil pressure to release the steering clutches, or possibly the brakes are adjusted too tight. I don't remember but on the "C" I don't think the levers operate the brakes as well, one of the "old CAT" guys will correct me if I'm wrong. I worked on "D" models, as I recall they had two actions, pull to the first notch was clutch release, all the way activated the brake on that side? Does the tranny pressure gauge on the dash work?
No.... the brakes on a c are mechanical.
No it does not but we did remove the the tranny pump and it looks perfect -- also loosened the line at the filter with it running and had lots of pressure ... I talked to a local guy at heavyquip after I found little roller bearings and a Teflon lookin washer in the magnetic screen and he told me we had tranny gone bad which I believe is correct .. He was a retired cat mechanic so I think he is right about that .. However he also told me that by pulling the steering levers this thing should roll --- so im just not sure why it wont roll but im assuming the tranny is completely locked up . Im no mechanic but im pretty familiar with this old d6 - ive owned it two different times over the yrs and its well worth fixin -- just need to get it pulled out of a bad place .
A 6C will roll without engine running. I found out the hard way trying to load my dead C 69J that while it will roll, there is no way to release steering clutches. Brakes work though. Steering and brakes are completely separate from each other.
Thanks , but the problem with this one is the tranny is locked up somehow I guess -- weve pushed on it with another dozer and tracks wont budge -- that's why im wondering how we might move it before pulling the tranny out .
Your not answering the questions. Do you have transmission oil pump pressure when running the engine? You need oil pressure to release the steering clutches. With proper pressure pulling back both steering clutch levers will release the steering clutches which disconnects the drive train and unit will roll whether the transmission is locked up or not.
There are two steering clutch pressure check ports under the seat. One on each of the pipes leading from the steering clutch valve back to the bevel gear case....one on each side that feed the clutch release pistons. Pressure should be 315 psi min. with the clutch lever pulled back. (pump pressure at the filer should be 315-350 psi) If something in the trans is causing you to lose pressure at the clutches you won't get them to release.... Difficult to move unless you have a way to get it up on a skid of some kind and drag it out. The only other way I can think to release the clutches would be to use another piece of equipment to supply pressure to the clutches, either just before or after the steering clutch valve. Would be a little messing around to get in plumbed up and the pressure would have to be regulated down to the 315-350 range.
A teflon washer and a few bearings dont make a blowed up traney. If you have clutch preshure at the 2 pipes comeing out of the steering valve with the handles pulled and you still no free roll than you have final drive/ brake prolems. With both clutches pulled and the motor running with preshure on both steering clutch ports does one track roll? Next is it a brake actuator or a final. I would start by checking the oil in the finals dust or junkiron in one or both will tell a tale. Also could be as simple as a brake pedal/linkage bushing stuck
Thanks , and that is a possibility -- we have not put a guage on the transmission pump -- we only loosened the line at the filter and seemed to have pressure . My next step will be to put a guage on it for sure ---- very helpful to know that if the pressure is good this thing should roll even with a locked up tranny . Thank very much
For your early s/n minimum operating pressure is 275psi. Maximum is 310psi.
Could also be something simple like the brakes are locked. Possibly with a malfunctioning park brake lock.
This thread is getting very interesting, maybe Traderbill wont be up for a very expensive rebuild,lets hope so.
had a 10k7037 d6c pinion bearing lock down how i had to get it to push was take bolts loose around trans tired trans to cab put two by fours in gap after siding trans and ringgear apart would roll then allso anther time had final go down pulled teeth off spocth where we could pull out and load to get to shop.