What is the maximum hours you would consider on a used dozer?
I try to get rid of mine at 7500 hours if possible. I have friends that rebuild and keep the machines up to 20,000 + hours. It all depends on what you want to spend your money on....
It depends on the model and age. You can economically rebuild a D10 or D11 and I've seen units up to 100,000 hours. Small dozers like a D3 up to D5 usually get up to the 10,000 area OK. You are looking at fixing major components after that.
Anything under a D8 sized machine isn't worth keeping past 10,000 hrs. The larger the machine, the more viable full powertrain overhauls are. Even D8s aren't worth doing more than twice, but D10s and D11s are worth rebuilding up to 100,000 hours in ideal conditions.
Depends how rich you are,if you can afford to buy a new D8, thats what you do. If your poor you rebuild it. Have seen plenty of D8Hs with 30000+ hrs on them. People in different countrys have different approachs to this. TCtractors in the UK rebuilds plenty. I rebuild mine, along with lots of other people in NZ Biggest thing is its maintence history; how has it been treated; and how much work does it have to do each year. And is other variables; clients may stipulate new machines; but do they want to pay a higher rate ??? Also depends on the style of machine. Hydrostatic dozers are a trade in machine; like diggers, nobody rebuilds them they go for new. Powershift dozer is more rebuildable. Also depends on labour costs here too obviously. For me time is usually cheap; if i can shedule a rebuild to suit which is usually winter. Machine brands play a part. As parts availability and choice is better with caterpillar than many others. ie new, classic ,pirate, 2nd hand. And you guys in the US have your emission laws. This is something i dont; and doubt i ever will have. So that throws another spin on things too. But rough rules of thumb to me D3-D5 10000hrs. D6/7 20000. D8 40000. bigger 60000 plus. Again depends how theyre treated, some will do more, others less.
The total tractor hours are not important. What is important is the component hours. You can buy a tractor with 80,000 hrs on it, and if it has been fully overhauled with all new components, it will perform as good as a new one. This is what you get with a Cat Certified Rebuild. Cat sales brochures from the 1940's show quite a number of the old Cats (now, "antique" Cats) with huge hours on them. One sugar cane farm in Hawaii had 5 gas Caterpillar Sixtys in the 1940's that had all done between 80,000 and 100,000 hrs. Cat say that most components are good for 10,000 hrs under average operating conditions. That drops to 7500 hrs under severe conditions, and can go out to 17,000-18,000 hrs under moderate working conditions, with good care. If you buy a tractor with 7500 hrs on it, then on average, 3/4 of its working life is behind it. If it has been lightly worked, stored under cover, and maintained without regard to cost, then you are probably buying a tractor that is halfway through its component life. The problem is that only a small number of owners maintain their equipment properly, without regard to cost. Most used tractors suffer from delayed or ignored maintenance, and are usually poor buys. If you can acquire the repair history of a tractor, you're way in front. I'd rather buy a tractor that comes with a long list of recent repair expenditure, than one with no repair expenditure history at all.
Thanks for the replies. Great info to have.
ditto what oz just said. great thing about old cats, they were built to be rebuilt.
I bought a 6R with 8200 hours on the clock, the contractor that had it since new built golf courses and all it did was shape mounds of fill, the hours didn't scare me, dozer still tight with shims still in place. Didn't have $400K for a new one
What i have is an old machine that was used in demo work, if i were to purchase another, then i would look for a low hour machine that was not torn up so bad. Also look at bending some wrenches on the cheap machines. sam.