I'm looking at a 2015 850K with 2900hrs and the saleman said it is in the shop getting rails and sprockets. Should I be concerned about the chain? Will it at 6000hrs need sprockets, rails and chain? This seams like a lot of ware items for so few hours. Granted I won't put 3000hrs on it in in the next ten years. I will be pushing out trees and building stock water ponds. TIA.
Well, the rails are the chain...........its just different terminology. Depending on the quality of the rails and sprockets, and what type of soil you are working in, will determine the amount of hours you will get. Keeping the track frame clean of debris will help also.
The biggest issue with a dozer is undercarriage. It is expensive to replace and you don’t get but so many hours. And the life you get out of it is dramatically affected by what material it is running in, what it is doing, how the operator treats his machine, and so on. I’ve seen fine coastal sand eat undercarriage in nothing flat and I’ve seen better soils and a frugal minded operator stretch the life to the max. typically our customers in my area send a dozer in for midlife pin and bushing turn with sprocket replacement then at end of life they get full undercarriage- idlers, sprockets, rollers, rails, and pads.
Most of the manufacturers I've looked at now days are using thicker bushings in the chains. The end result is being able to run until the links are worn out without having to turn the pins and bushings. Most all dozer undercarriage runs between 3,000 to 5,000 hours depending on the variables mentioned above.
I can't remember the last time I saw pins and bushings turned. Maybe in the late 80s?
I can't even remember the last time I saw a turned pin and bushing job. I know aftermarket rails are about the same price. I haven't seen bushing turns since the early 90s
It's still done, but you'll see it more often in constant production machines where they're trying to get maximum life at least cost over the life cycle of the machine. With improvements in the sealing life of the wet joints and stepped bushings for thicker walls they are getting link height wear well beyond 100% by the book nowadays before the bushings are gone.