I would make a little money with it. I occasionally sell firewood off my property. But mainly for property maintenance. Road grading, clearing downed trees. Also have a sawmill for personal use, so skidding logs.

How many hours a year and under what type of conditions -
Rock - sidehill, dirt, etc. Many here can confirm -- even with new grousers and plates, a CAT can go "skating" on rock.
Many times it is much wiser to lighten the loads and make multiple trips - each situation requires thought and planning.
Speed is the enemy with steel tracks - faster they go, the faster they wear out and the more hammering effect on all components!

When you consider Grouser Height -- every condition is different - I have worked ground so hard and dry that a 3T D-7 barely left a mark, and other places where you were full depth and plugging up with dirt. Like everything else -- the more "bite", the more strain you will put on the rest of the components in the system, all the way from the engine to the pins & bushings!

New Bolts, cinch them up tight!

I have had track rails (Links) break at the bolt holes, that being said - if you ream or drill them out, you weaken the link additionally.

Many "old" machines ran for a long time with very thin rails, idlers, rollers, etc --

There is no simple way to work on individual links in a "chain" - it requires total dissassembly, "TRACK PRESS TIME" and you do not want to be in that if at all avoidable, costly to say the least!


CTS

 Rock - sidehill, dirt, etc. Many here can confirm -- even with new grousers and plates, a CAT can go "skating" on rock.

I have had track rails (Links) break at the bolt holes, that being said - if you ream or drill them out, you weaken the link additionally.

yep ive had that happen. the first time if your not expecting it gets the heart going. it was a single rock on the side of a hill and i only slid sideways about a foot but it gave me a scare.
the cousin was walking the machine back from where they were working he had his duaghter with him the d4 slid about 2 feet while going round a hill she stayed for the first one the second time she bailed out and walked till they were on flatter ground. she was around 10 or 12 yr old.

worn bolt holes thats why i suggested welding them up with bronze and then re drill to size rather than using then using bushings or fitting larger bolts.