DT 466E Question

I serviced a large fleet using this engine. We had a steady diet of random liner packing failures for a long time. The O-rings are at fault here. When they fail, the coolant leakage allows air around the liner overheating the cylinder sometimes scoring the piston.
At minimum, all liner packings should be renewed on all liners or others will randomly fail down the road.
We made it standard procedure to buy an overhaul kit and refresh the engine at the time of first liner packing failure. There were no more failures of liner packings after overhaul.

 

I think that's the best choice, unless of course someone is on a tight budget. The overhaul kits for these engines is very reasonable and the labor will already be there replacing all the liner packings.

 

I was going to say too the orings are just junk. Most of the engine's oring seals reacted bad to the orange coolant and shrunk after a few years, so they would leak. Leaking front covers was the usual dead giveaway. The overhaul kits are good. The seals are fully compatible with orange, (long life) coolant. These motors are pretty cheap to overhaul.
kgktm what year is your truck? Does it use orange or green coolant?