We have had several input shafts snap behind the C15s. All different drivers. One snapped at enough an angle it would still drive the truck, til it forced the input gear through the bearing and toasted the case and everything.

I had a horrible shake with a 3406E in an FLD. Shop couldn't find it, til the day I came in and hit the clutch while one of the mechanics held onto a mirror bracket. I had three bolts holding the tranny to the motor. ANd they were only a few turns in. Less than 100K on the clutch. Took a clutch, input shaft and bearing, pilot and throwout bearings.

 

Those pictures are why I own and operate my own tractor. I have 735,000 miles on the original clutch and u-joints. I am permitted to run up to 90,000lbs and do it regularly. You have to go slow and easy until you get on the big road then let her rip.

 

I drive in the oil field and it is not uncommon to see a person put a new Pete or KW into a mud hole and then try to get it out and break something. Usually it is a u joint, axle or mount.
But trannys do go, I have done things to trucks that would make most highway guys cry in their sleep just to get out of a bad situation.
Parts break and drivers get blamed.
If you have a bad driver then fire him, if he is still working for you then there is a reason. Maybe the damage was not all his fault. You can't always blame the driver for everything mechanicle on a truck. Especially if it has been used by multiple people.

I go through less brakes then most because I have my Jake on 98% of the time. That includes ice road in the hills highways etc. I usually onl;y use my brakes to make the actual stop, the rest of the time I slow er with the engine.
The other guys I work with are always using their brakes.

 

Last place I drove class 8 at had so many monkeys busting transmissions they finally decided it was cheaper to spec all the new trucks with auto shifts. Apparently, before changing to auto shifts transmission repair was their single highest maintenance cost by a large margin. I never found it so hard to listen to the truck and let it do the work, all that banging into gears is a good way to work up a sweat!

 

we had a guy in out kw t-6 triaxle dump and i guess the trans bolts backed out and the shifter started moving to weird position and he never said anything until the day he was backing into a job and it all let go. the shifter flattened the pass. seat then broke it off, then spun under the truck tearing out cross members, air lines, wires, ext. ya that was fun

 

I see these failures alot. Shock load (dumping the clutch) causes a deep root tooth extraction. You have a clasic PTO root failure. Pieces from the pto caused that. We service vac trucks and that is very common. Do not over look that PTO. Just my 2 cents