2018 Denali 2500HD Pedal Vibration

[4thDmax]

In order:

-2007 GMC Sierra 2500HD SLT 217,000 miles

-2012 Chevy Silverado 2500HD LTZ 105,000 miles

-2016 RAM 2500 with Cummins that I put 14,000 miles on before trading in to get the 2015 Chevy because I couldn't stand the transmission always hunting and slipping

-2015 Chevy Silverado 2500HD LTZ 70,000 miles

-2018 GMC 2500HD Denali 8,000 miles-current vehicle

 

I'm on my 4th 2500HD and all have had a slight accelerator pedal vibration. Enough to be a bit uncomfortable but not enough to make me want a different truck. I think the Duramax/Allison combination is pretty spectacular and the truck itself fits me perfect. But, the vibration issue has been a bit annoying and this truck is just about intolerable. The first 2500 had a vibration that I took to the dealer a couple times but realized was fairly normal for this truck. 

 

The pedal vibration in all the trucks was pretty constant throughout the rpm range and at idle. I started this thread because the main vibration issue I find in all these threads has been driveline, tire, suspension, etc. 

 

I bought this truck with 5k miles and have put 3k on it in a month and a half. Anybody else have a pedal vibration that seems related to engine rather than suspension? It does get worse at certain rpm but even at idle it's enough to make me want to put a back scratcher in my right boot and scrape some skin off my foot. Drove back from the slopes yesterday and couldn't wait to get out. My foot was numb and the love was gone. I bought this Frost White Denali thinking it'd be the truck I put a few hundred thousand miles on but I doubt I'll own it until it hits 10k if I can't resolve the shake. 

 

Any info would be appreciated. Everything about the truck fits me perfect but I'm considering going a different route soon if this can't be resolved. Local service tech kinda gave me the that's normal response.

 

Also get a whiff of coolant in the cab on occasion and she's used a reservoir of coolant in the first 2,000 miles. Was full when I bought it and almost empty after 2,000 miles. Filled it at the dealer and it's down half in 1,000 miles.