I have the caterpillar 931 track loader. Mits 4204 engine. 3 forward and 1 reverse power shift transmission. Some problems have been developing. 1st, 2nd gear went out. It just slips. I was told by the dealer the clutch pack probably needs replaced. I was told to run it in 1st 3rd, and R until I want to drop coin on a rebuild. All was fine and I was living without 2nd gear. Now some new gremlins are showing up. The machine will run for around 15 minutes. It drives and steers fine. Then it starts slipping out of gear. It slips out of all of gears and makes slipping noises. If the gear engages the steering stops working. You can hear something under the seat sound like its engaging and disengaging. The machine will start lunging and then stop moving all together. If I let the machine cool down, it will run for another 15 minutes and its an exact repeat of the above. Sometimes the machine will act fine for hours. But then all of a sudden, the gremlins return. Fluids are gold as honey and over the top line on both sticks under the seat. Temperatures are low. 50% engine. 30% converter. A local dealer drove it around and said they couldn't get it to do anything wrong. Charged me $500 for a couple hours of play time in the seat. They did not measure any pressures..... Opinions please, Tranny, final drives, pinion gear? The machine has a great under carriage. The motor is a fresh rebuild. Brakes and clutches are very good. I hate to give up on it but Im scared it is about to become a 10ton paperweight.
Have you tried pulling filter and suction strainer out to see what is in them? Always a good place to start.
My 931B has a 3F/1R trans. Take the 3 bolts on the cover for the suction screen out and check the screen. The 3F/1R trans doesn't have a filter. If there's a lot of black particles you're clutches are going. When I had my engine rebuilt they checked the screen and said it was a good sign it was clean and black particles indicates the clutches are going. The engine and trans come out as a unit. Cat are generally good transmissions. If the rest of the machine is in good shape it's worth fixing. Yeah it can be expensive but a new machine would be over 150K.
I don't understand why the dealer had no problems, if you have a transmission problem, you can smell ,like brakes. Ck the floor cover off, move the brakes, clutches. Make sure all is tight with the leaver, loose, and ck the springs, and the mount for the hydraulic control. Don't forget the flashlight. sam.
Yes, dealer drove it around on a joy ride and did not do anything else. $500 for a joy ride....... No smells. Just slipping and noises once heated up a bit. Fluid is gold as honey. Thanx.
It sounds like the control cable is not right, or the hand control is loose. have you cked drive shaft, and drive systems. You could remove the top of the transmission and ck the pump, and Only rings. Do you have a repair manual, the dealer could give you a print of the parts, give it a power wash and take a good look. Sam.