Air intake melting at turbo

Turbo cooled and lubricated by oil and air from the engine fan. Oil is cooled by your radiator and water pump. Did you notice your oil temp or coolant temp very high while driving those miles? I would look at your fan clutch very close or the solenoid that controls the air to it also. If there was enough air flowing thru the engine bay then it would cool it sufficiently. Will your fan lock up or does it free spin wether you have air supplied to it or not?

 

The fan turns on but does it lock up with the engine side good or is the clutch worn real bad and it just slips a lot of the time? Turn engine off with air applied to fan clutch and ignition turned on. Is fan locked up with engine? Now remove air from the fan clutch...is fan locked up with engine? Does it spin easily in both conditions? If spins easily both conditions time for new fan clutch. Detroit in a Volvo that fan clutch was 600$

 

Only other option I can think of is to check your air filter. If you do not have good air flow to your turbo you will choke your engine, get less fuel economy, less air flow to the cool side of the turbo. If that is not it then you need to install a modified heat shield between your manifold and your turbo to mitigate that heat away from your new turbo. I am just giving you logical solutions to try to solve your problems to help you out. Good evening.

 

Plastic? On a turbo connection? Good grief, that doesn't sound right considering how hot a turbo gets.

 

Yep, Freightliner did it on big bore engines for a few years as well. As far as turbo getting hot, check air cleaner like someone stated and for any leaks in the intake system. A lot of C7's utilized a "smart" waste-gate that could cause issues as well. If I remember right the solenoid was on the left rear corner of the block, real easy to access! LOL