UWSkier

Bumping up this thread to see if the forum has found a solution to the excessive DEF consumption while towing. I currently have a 2016 5.3L and am about to pull the trigger on a travel trailer that will likely be about 7500 lbs loaded (boondocking with full tanks). 3/4 ton trucks don't fit in my garage since the manufacturers are all designing them with "I'm gonna be a big rig when I grow up" in mind. Strongly considering the updated 3.0 Diesel in the '22 for my next rig. Or an F150 Powerboost. I plan on towing annually from Arizona to the Midwest and back and don't want to be stopping to add DEF every 300 miles.

Been following this thread as I've had a shaker of a Denali for over a year. Replaced most of the tires to RFB them which made it better, but then on first tire rotation, problem came back. It spent all last week at the dealership. GM ended up swapping out the Goodyear Eagles that came on it with some Bridgestones and the problem seems better on first drive. Fingers crossed it stays that way, but I gotta wonder if the different tire is a different durometer or something and just masking another problem.

Mine vibrated at 26 miles, driving it off the lot on delivery. I got the "it's the tires" excuse and was told to drive it a bit to see if it got better. Wish I'd known. See if they'll put your current tires on the Denali you want, and drive it. If your current set is supposedly RF balanced correctly, the new truck shouldn't shake. If it does, ask to try a different one.

Did it feel like a shaft wobble (i.e. bad u-joint) vs tire? They feel considerably different usually. Mine definitely feels like it's tire frequency, but it could be a harmonics issue I suppose.

My '16 Denali has 6660 miles on it. Still vibrating after several sets of tires. I'm also in the 70-80 MPH camp. When it was in last week for another attempt to fix the vibes, they gave me a '16 Crew Cab Regular Box 4x4. Had that running at all sorts of highway speeds and rode like a luxury car. Wheelbase have anything to do with it maybe? Anyone with a 6.5' bed Crew having the vibes?

Newb here, joined just to join this thread. 2016 Sierra Denali short box. 5.3L Noticed a vibration with 26 miles on it taking it off the lot. Dealer said flat spots on tires and give them a couple hundred miles. 75-80 MPH is the worst. Definitely feels like wheel frequency, not driveshaft. I've had bad U joints before and know what driveshaft vibration frequency feels like. First visit, 600 miles, replaced 2 tires and rotated a third on the rim. Definite improvement. Second visit, 3000 miles, they said one of the rears they put on as a replacement went bad. Third visit, 6500 miles, different dealer this time. Manager takes it for a drive and finds vibration. They road force test all four tires, and they're all single digits. Re-mount and "no vibration detected. Operating within spec." Third visit was today. I'm not optimistic the problem is fixed. Will know more tomorrow. If there's a fourth visit and it's not fixed, WI lemon law kicks in and I'm going after GM. I really really love lots about my Denali, but I really really miss my Titan for other stuff. Never had any mysteries with that one... So you guys chasing shocks/struts, that's probably not it. Magnetic ride has the same issue.