What's the worst damage you have seen to a drivetrain?

Ugh I could make a list.

T600 with a n14. Clutch disk stuck thru flywheel housing. That was a mess of torch and air hammer to get it apart and remove trans.

15 speed in l9000 6axle straight truck. Driver claimed to have knocked it in low range at 70 mph on interstate. Input shaft in 2 pieces. Reused the main case only. I doubt that's what happened. But it was his story.

Owner I worked for in a new 84,000lbs WS rotating wrecker towing a wrecked tractor trailer. Oil on boots, foot slipped of clutch at red light. Grossing 164k ish. 52,000 diffs.
Broke input shaft like you sawed it in a band saw. Never seen such a clean break.

Seen a Dana Spicer with ring gear chewed thru back cover and hanging out with broke axles.

But the worst were normally anything w/pto. Normally out of oil do to leaks. All teeth missing on main/counter shafts. Insides are powdered metal.

More I think, the more I remember. I now have the smell of burnt gear lube in my mind sitting in my living room.

 

Victim was a 4 axle Rollback for big dumpsters. Unit was towed in for CEL and was derated. Engine repairs were completed and the unit was being driven to a local body shop for some hood repairs and paint work. 3 piece main driveline. 3 Miles from the shop the rear section came disconnected behind the second carrier bearing and fell out at highway speeds. U joint cap bounced off the service truck windshield, which was following the truck to pick up the driver. The driveshaft stayed on top of the pusher axle and flopped around inside the frame-rails like a largemouth bass just hitting the bottom of the boat.

2 air tanks, brake valves, almost all the air lines to the brake system, main chassis electrical harness got wrapped around the shaft and peeled it apart half way to the front of the truck, hydraulics got hit on the roolback, plus the driveshaft. Near 20K before we were all done.

We tried to go after the tow company as they installed the driveshaft with old straps and only installed the bolts finger tight. Tow company didn't deny leaving them loose and claimed " that's how they always do it".

Very big lesson here- We always document when axles or driveshafts are pulled on the check in sheet. And "WE" reinstall them. Tow drivers are no longer allowed to work on trucks on site. They are to drop the unit and leave.

 

Not truck related but had a D8 that the transmission would overheat and stop moving. Pulled the powertrain filter and lots of glitter. Drained out the oil and pulled the screen. Lots of loose bearing rollers in it. One of the bearings broke apart on the input shaft.

 

20 years ago I show up to work boss is tearing a strip off a experienced driver . It’s January and minus 30 driver got stuck in his parking spot he hit the 4 way locks and then stood on the fuel when it engage he ripped the whole crown gear out on rear axle it went right through the housing.. his lesson was one for me I always lock 4 ways in winter when I park for night if parked in a slippery snowy spot .even if they disengage from losing air they lock up right away when cold because everything is still in line.

 

Is it alright to disengage while moving?

 

Oh man, had one very similar. What a nightmare. But it was customers doing not are shop.

Other nasty ones. Had a flatbedded on turnpike. His rolled up tarps came of the front of trailer. Got into drive shaft. Wrapped 48 foot of tarp on shafts. Pulled ripped every air line, elec harness. Started to try and cut with razor. Ended up unhooking it right in the third lane and rear tow to shop. Then spent hours cutting tarp out. Lol.

Had another that a yellow strap came out of big shinny headache rack at highway speed. It actual bent rack in a V and was sucking it down between frame. Pulled all electrical, and coolant lines out of the floor in a 6 month old W900. Cut everything inside frame railes. Ruined one air tank. From a yellow strap.

I'm getting chills remembering this stuff.

 

That sounds expensive.

 

Probably was. I've only ever rebuilt a D6 transmission and honestly it was easy. Much easier than rebuilding a GM TH350 anyways.

 

I wouldnt know. Only done maintenance, pins, bushings, track repair. Engine work. I know zero about trans and finals in that stuff.

 

Long before I started in a class 8 truck in the late 80s I ran a gas powered chevy c70 wrecker with hydraulic brakes.
One day the micro brake switch wouldn't release the brakes while hooked to a large straight truck so I gave er hell ...Driveshaft twisted in half , Boss was real happy that day .