I have an 2018 GMC Canyon All Terrain Duramax. I towed my 29' Mod V back from Moabi in the spring with no problems. Boat with 90 gals. of fuel weighs at least 6500lbs.
My son took my 06 2500 HD duramax off my hands when I bought the Canyon. I Love the way this little truck drives.
If you google UFP (unique functional products) a website will list several new calipers in the $60-85 range. Extreme helped me with p/n issues when mine froze up 5 years back..
My 04 1/2 LLY, 165K miles had the same code a month ago. Found an AC Delco module on E-bay for about $80. Easy to change, working great.... BTW, I have never had to change a glow plug yet.... Hope this helps...
The priming pump can be rebuilt for about $25 for the o-ring/backup kit. My 04 1/2 Duramax would loose it's prime once a week, crank, but no start until I bled the filter . Ebay has a Dorman p/n 904-124/904124 kit for $24.95.... Easy to rebuild..