Just started doing this and have no manual to troubleshoot. It seems as if it is a low fluid situation with the transmission...just a guess. Hyd. filters were changed 400 hrs. ago. Is there a place to check trans fluid, or is it even separate from the hydraulic reservoir? Thought maybe water in fuel at first, but serviced the separator -engine runs fine. Runs and pushes great on level ground, shifts well, etc. Thanks for any help!
Hyd level sight glass right side back of machine same oil does all
Thank you for your reply. That's what I was thinking too, so maybe some filter issue at play (site window full). All works fine until it gets on an incline and acts as if the trans is slipping.
I bought one at an auction yesterday and now I have problems with it too. (need to get 3 post so I can thread start)
You have access to pressor guages? I can e-mail you the hydraulic test proceedure and specs, you will need the quick coupler on your pressure guages
I have a Cat D3G 2005. The hydrostatic fluid serves both the drives that turn the rear sprockets and all hydraulically operated implements such as blade, ripper, winch,etc. There are two dual hydralic pumps under your feet which can be seen when you pull up the floor mat and remove the access panel. They do the whole job. Hydrulic fluid is pumped from the pumps to the drive motors. There is not a transmission as such. The hydrostatic drive is based on the hydraulic controls that tell the pumps what to do. I have been through this a while back and did know more and could look it up if I had to. As was mentioned, if the machine is level the sight glass should tell you if you are low on hydraulic fluid. Yes there is one hydrulic tank that is mated to the fuel tank. The hydraulic tank in on the operators right hand. Does the engine power up when the governor is moved all the way back? If not then it may be a fuel supply problem. The only trouble I had with mine was the fuel/water separator stopping up because there was debris in the tank. Had the tank cleaned and all is well.
How much of an incline are we talking about? A gradual climb or a steep climb? I'm not an operator so I don't know about % of a slope. We used to have a D5G when they first came out with hyrda-stat dozers. Two things that I found to be their downfall: 1.Best I can remember they didnt handle a 30+ degree slope too good unless you were pushing downhill. The reason for this was going uphill your supply oil ran to the back of the tank while your supply line was at the front of the tank and not at the very bottom. The tank only held maybe 5-7 gallons of oil. The second thing was on the joystick you had your HI and LOW speed selector. I dont remember if on the dash there was a warning light that lit up when you were in the high side or not. We ended up having to replace the hystat pumps because they wanted to do hard pushing in the highside. The later ones were variable speed and had the gauge on the dash with the little track and 1,2,3 and a needle that would show you your speed.
My D3G (also a 2005) will go up very steep hills. I used it to pull a hugh red oak saw log to the barn this summer. Here in my part of KY it can be very steep coming out of some of these hollers. It did not even strain. I could hardly tell there was a load behind me. I went straight up the hill which was the safest bet. As you say the 2005 Model has the speed control on the drive joystick which will be in the operator's left hand. The hydrostatic speed control has infinite speed setting on a guage from 1 to 3. The numbers are of no importance as the speed will be whereever you stop the needle. There is no warning light. The hydrostatic drive guage is in the center at the top of the dash. There are 5 guages that surround the dash light package. The left top guage is oil pressure. Then the hydrostatic speed meter or guage. Then engine temp. The two on the lower tier is fuel and hydrostatic drive temperature. The speed guage is simple a needle that swings anywhere from 1 to 3. Speed is selected when you release the button on the joy stick.
The hydraulic tank service refill capacity for a D3 G Series 2005 model is 12 gallons. Mine took 14 gallons to get it where it was suppose to be. The D4G 2005 should be the same. Second, the transmission is the dual-path, closed loop hydrostatic drive positioned between the two final drive motors. The hydrostatic drive provides infinite variable speed from 0-5.6 forward and 0-6 mph reverse.
For additional info to what inyati said, the dealer can also change the speed settings on your dozer. For example, when I bought my D4G new, it was set up to reverse at 150% of forward gear. What I mean by that is is that if you had the hydro setting on 1 on your speed gauge, when you backed up the speed was automatically 1.5 times whatever your speed setting was so it was much faster. I pushed a lot of brush with mine and didn't like it, so they changed it to where it was equal to whatever the forward speed was. Also, I had them change the highest speed of mine from 5.6 mph forward down to 5 mph (or maybe 4.8 mph, I can't remember) to keep operators from running high speeds to try and save on the undercarriage wear. All they have to do is to plug in their computer to make these changes, so it's not costly.
d9gdon, that is something I also have noticed. I would like those same changes. When I am working, I would rather have it reverse at the same speed I have it set to go forward. I will call my Cat dealer! Thanks.
I feel rather silly. I just noticed that this post is almost a year old!!!
Not to worry! I'm still here...the machine was a rental I was using. I never found out what the problem was as I returned it...and bought my own.
Aww hell....since it was a rental just do what everybody else does...drive it like you stole it.