Can someone let me know how difficult it is to disassemble/reassemble the final drives on a d5g. I want to inspect the gears and replace the duo-cone seal. thanks ken
I cannot really help with a direct answer but I was curious about your thread because I have a D3G 2005 which has the same final drive as yours. Are you having a problem that makes you think the gears are damaged? Second, is the seal leaking? The only help I can give is to go to a Cat dealer website and look up the exploited diagrams to give you a start on how it all goes together.
Its not leaking that i can tell. It's the oil analysis. Report says dirt getting inside. Silicon levels are very high, along with iron and aluminum. The oil is red flagged for the last 700 hrs at least. I figure the seal is worn out. I also want to go inside to check the condition of things. Do i need a password or something to get into the exploded drawings. I'm going to check that out right now, good idea. Ken
You can set up an account/password on most of the authorized Cat dealer sites. Here in KY I get on the Whayne Dealership site. I just looked at the final drive. Getting to the duo-cone seal does not look all that bad but to get to some of the gears behind it will take more effort. By the way, you will need an online account set up. Go to the parts store. I have been told the parts store is the same one for all dealers as it is hosted by Caterpillar. By the way, I farm also. Beef! Its what's for dinner. Ron
Got it. I set up an online account, but it needs a few days. I have done the duocone seal on an excavator, and was amazed at how simple it all goes together. I expect the dozer planetary is the same thing. I do want to pull the cover off the gears behind it though, just to make sure nothing is going on back there. Also, i'm worried if i get into it and decide we need bearings and whatnot, i will need tools only CAT has.
The silicone could very well be from dirt entering through the seal. I'm not sure what component, in a final drive, is made from aluminum. The iron could be from gear or bearing wear. Every time I have had elevated silicon levels, in a sample, I had oil exiting the compartment too. Maybe not enough to drip but certainly enough to make dirt stick to it. Food for thought: I'm not sure how often the recommended sample interval is but I'm sure that the oil has been contaminated longer than 700 hours. IMO the iron is NOT coming from outside the compartment. That combined with the high hours of the machine (I assume it's the same one you were looking at before), and the extended operating time with elevated contaminents, tells me that the final drives are nearing the end of the road. Visual inspection may not reveal much but the sample has already told me enough. If you haven't made the deal I would stay away unless you are willing make repairs to the F/Ds at some point.
I think I would get another analysis lab to check a sample. I can't think of any reason there would be aluminum in a final drive. Also along those lines I have never seen a final drive sample that didn't show high iron. I have pretty much given up on oil sampling on self contained compartments like final drives and swing reducers. Just another note here, silicone is used for sealants and lubricants and has no relation to dirt which is silicon. You might state here just what the levels are in the reports that are being flagged as high. What I have found most of the time is that what is high for some is normal for others. It also depends on who is interpreting the results.
It is a pretty straight forward design. I rebuild them on the machine. Grease up the pinion bearings when you assemble the final so the rollers don't hang down and stop the shaft from going in. Before you take it apart, check the parking brakes first. They are also lubed by the final oil and if worn out could be causing the wear metals. BTW, classic parts are avalible.
I tried to upload the actual fluid report, but its too big. The 5000 hr sample is the first bad one. Before that, the 3600 hr sample was good across the board. There is about 5700 hrs on the unit now. So, Iron jumped to the mid 500's. Before that it was running around 100. Aluminum jumped from 6 to 85 at the same time. Silicon jumped from 36 to 353 to the low 200's at around 5000hrs as well. The most recent sample was done twice, for confirmation. Identical results. Potassium is running high too, for some reason. Now water was present in any sample. Too bad i can't upload the analysis report. Thanks for all the input guys, i really appreciate it. Ken
Thanks a ton for the parts blow up. That helps a ton too. I talked to the dealer service manager. He brought it to my attention that my track may not have a split link track. I checked and sure enough, so i'm not sure i can split the track. I did my excavator track, and splitting it wasn't easy. After much haggling with the sales rep, i was able to talk to the branch manager who has the authority to commit to a deal. Previously, i was dealing with a rep who had to go back and present it and blah blah blah. Its just so much nicer to go right to the guy in charge. Anyway, the deal is I bumped my offer by $1500, they will cover all float charges, R+R both final drives, install two new duocone seals. Once they get it apart, I go to inspect the remaining parts, I decide what i want to do to it after that. Best case, i get new seals installed and the tractor is good for a long time. Worst case, i spend a little more, and get final drives that will be as new. Either way, i figure my money is well spent. And either way, i can't find a tractor in any better shape for any less money. My next choice after this unit is about $15000 more. So I can afford to spend a few dollars on this one to bring it up to spec. Thanks again for all the help.
Sorry, I did not mean silicone sealant. I meant silicon like dirt. Drop the E.
There is a second D5G i am considering. When the first deal seemed to have failed, i called this second one to get oil samples done. I got the results yesterday. As it turns out the oil samples came back almost exactly the same. Coolant, hydraulic oil, engine oil, all in good shape. The final drives were both red flagged with Iron, aluminum, and silicon levels 2 or 3 times higher than the first tractor. Kinda makes me think they are all that way, and maybe the first tractor isn't that bad after all. I will have to send a little cash to the other guy for the time and cost of sampling. I don't mind paying a little for information, it's worth it. Thanks for all the input guys.
watglen, I have a D3G 2005 which is basically the same machine. I have had no red flags on final drive oil samples and all metal levels are listed as normal so I would not get into the frame of mind that this is just the way it is.
Watglen, is there any chance that may be those dozers may have been under water?
I don't think so, good call though. The unit i am looking at spent its life doing final grading ahead of the asphalt on road building. It is a one owner unit, a paving company. Talking to the owner, it sounds like they have dedicated operators on their units.
The deal is done. They had both finals disassembled yesterday when i got there to inspect. There was minor wear on one of the main bearings in the left planetary. The same bearing in the right unit was showing significant spalling. It wasn't going to be long before that bearing started to disintegrate. Missing metal flakes were easy to see. The duo cone seals were completely shot, worn almost right through. Gears and such were all in great shape though. So new bearings and seals and button her back up. I couldn't be happier. Now i know the machine is going to be a great unit for me. And Toromont was fantastic to deal with, contrary to my initial assumptions. Probably have her home by the end of the week.
Congratulations. I like the G model D3, 4, and 5 machines. Should give you lots of service. Let us know how it does.
I still can't understand how it has the original undercarriage. The mechanic told me it still has maybe 2000 hours left in it, with 5700 on it now. It must have spent its lifetime idling.
I agree, watglen. I have a D3G LGP 2005. It has a total of 2000 hours and they are correct as Cat has a good record on this machine. It was used to push flyash which was tough on the bushings. I had a recent full undercarriage evaluation and the specialist said I could get at least another 1500 hours out of it or more. That would put the life of the undercarriage at 4000 hours. It is a nice machine. In very good condition. But getting 7,700 hours out of yours seems incredible.