Failure mode - Cummins 6.7L ISB (Ram HD)

Grid heater 'killer bolt' ingestion

Reliability tier: verified - verify before ordering, see /disclosure/

Symptoms

sudden loss of power / loud bang and metal noise from the turbo
turbo wheel damage found after a bang; compressor wheel shrapnel into the intercooler
hard cold starts / no grid-heater cycling when the heater itself has failed separately
the center grid-heater bolt visibly loose on inspection (found before it lets go)

Root cause

The intake grid heater is held by fasteners at the intake horn; the center bolt ('killer bolt') can loosen with heat cycling and vibration. If it backs out fully it is ingested straight into the turbo, destroying the compressor wheel - a known 6.7 failure mode affecting 2007.5-2024 per DPP (whole production, both this platform and the 2019+ generation).

Diagnosis

wiggle-test the intake horn / grid heater fasteners at any service visit (DPP-recommended check) - loose = replace the bolt with a retention/upgrade kit NOW
after a bang: borescope the compressor wheel and charge pipes for aluminum shrapnel
check the intercooler (CAC) for debris before restarting - shrapnel travels downstream

Fixes

prophylactic: replace the factory bolt with a retention/upgrade kit (e.g. threaded one-piece designs) - cheap insurance against turbo destruction ()

grid-heater-bolt-kit (part category - specific model not chosen)

after ingestion: turbo replacement or wheel repair + full CAC/charge-pipe cleaning and inspection ()

vgt-turbo (part category - specific model not chosen)

Prevalence

common