2020 Exhaust System

[SoTxPollock]

New 2020 GMC Truck purchased and while checking out the massive exhaust I noticed the extension on the end of the pipe giving the impression of a much larger exhaust. To my surprise the end of the pipe necks down to a 2 3/4" opening. That has me worried, on my old truck I had an exhaust temperature gauge so I could monitor the heat on a long pull. The new truck has no exhaust temperature readout anywhere I can find. It's the LP5 Duramax rated pretty high in torque and hp. Is 2 3/4" enough opening to get all the exhaust gases out without overheating the turbo? Can the opening be increased without setting any codes?

[DmaxMaverick]

A larger exit may be beneficial in some ways, but would certainly compromise the designed DPF regeneration process. The tailpipe is designed to cool the exiting gases to some measured degree so we don't set pedestrians on fire (hard-learned Ford lesson). Any modification or aftermarket solution must take this into consideration, as well.

As far as the size vs. power vs. heat goes, they aren't blowing up while making ridiculous gobs of power, so it may be a solution in search of a problem.

[MikeandDollies2500]

I have been wondering the same thing about the smaller exhaust pipe. We don’t want speed just towing capacity and durability. We hope that this is the last vehicle that we buy. We’re close to both of us being retired.