Solving the 6.7L Cummins’ Head Gasket Issues—For Good
The 6.7L Cummins is hard to beat in the diesel world. The common-rail inline-six features the longest stroke, the biggest bore, and the most displacement in the segment. Its ability to spool an S400 has all but killed off the need to run compound turbo arrangements, and the stock injection system can support 550rwhp or more. Unfortunately, head gasket failure is a big problem in the 6.7L world—especially on trucks that spend their lives tuned and hooked to a trailer. We’ve seen some go 200,000 miles before lifting the head while others can do it in half that time. With a second-gen turbo swap, an S467, and aggressive tuning onboard, the 6.7L fourth-gen in this article pulled off the feat in just 114,000 miles.
Luckily, the owner plans to keep his Ram for the long-haul, and as such decided to do things right the first time. Instead of sending the head off for a simple pressure test and resurfacing, it was shipped to Scheid Diesel for a few additional reinforcement measures. And thanks to Scheid’s quick turnaround, a decked head cut for fire-rings and fitted with screw-in freeze plugs was returned to his doorstep in just four business days. Between the addition of fire-rings, ARP head studs, and screw-in freeze plugs, the head is about as bulletproofed as it gets for a 550rwhp truck. For a look at what the two-day job entailed, along with a glimpse into the hot re-torque process that’s required when running fire-rings, keep reading.