Stex

GM service department should run an oil consumption test. SOP. If it is outside of GMs consumption parameters, GM will repair. IF they cannot fix it in the given time, then you have wiggle room on another ride from GM.

My understanding is the 3.0 cost is about the same as the 6.2. $2,500. the 5.3 is not free. I think it's cost is about $1100. So we are talking about $1400 additional cost? The articles I have read said that the 3.0 weighs less than the the V-8s. All reviews so far say that the 3.0 460 ft lbs of TQ get the truck around town much better than the v-8s. Some reviews say the 10 sp tuning matched to the 3.0 is the best driving drive train of the line up. Only negative I see is the first year potential issues. But it has a 5 yr 100,000 mile warranty. That said, I have the 5.3, 6 sp. , 3.42s and it is a dog. Even after a tune. If I was buying today, it would be the 6.2 or the 3.0. (To be determined after a test drive of each). No more 5.3s for me. Two reviews attached. https://autoweek.com/article/car-reviews/2020-gmc-sierra-duramax-diesel-first-drive-smooth-operator

Only miles will tell if DFM is a problem. Hope they fixed those lifters. And the DFM does have as much if not more than AFM going on mechanically. And the software and number/swiftness of decisions the ECM makes ....Tech article: As you probably are aware, AFM was a relatively simple system which converts a V8 engine into a four-cylinder (operationally) by deactivating four cylinders. DFM expands on this idea by installing the AFM style, spring-loaded lifters in all 16 positions so that all eight cylinders (instead of only four) can now be selectively deactivated.......Mechanically, DFM is just an extension of the earlier AFM system. They have levers in the lifter deactivation chain. As to running smooth and cannot tell DFM is there, see this: more mechanical , These new DFM-equipped trucks and SUV’s will also be upgraded with what GM calls a “centrifugal pendulum absorber” in the torque converter. Essentially, this is similar to a dual mass flywheel for a manual transmission. This pendulum absorber employs coil springs mounted to a plate splined to the input shaft of the torque converter. This pendulum device will isolate noise and vibration between the engine and the transmission. When cylinders are deactivated, the number of crankshaft rotation increases between firing pulses. A V8 firing all 8 cylinders sees 90 degrees between combustion events, while a 4 cylinder engine lengthens this to 180 degrees. That inherently less smooth operation requires additional NVH dampening. https://www.enginelabs.com/engine-tech/gm-escalates-cylinder-deactivation-with-dynamic-fuel-management/

Oil soaked Piston rings on my 09 at 50,000. CC on now but too late. Has GM improved on this? I don't trust them on that or AFM/DFM. GM runs a CC set up on the Camaro now. Up to each GM owner but I would run one on anything GM or other makes....

Just not good. GM should make everyone whole on this leaking issue. A Cover buy back seems in order. Not even close to the look, but I went with a one piece undercover just to assure a weather tight fit. They Even have dust kits to keep dust out of the bed. Easy To remove. light and one can stand on the unpainted ones. https://undercoverinfo.com/undercover-classic

Thank you. And Nice truck! GM Finally has some nicer wheels for the 1500s. The GMCs where really strange when I bought my GMC. Chrome clad wheels back then. I have been running 18s, due to pasture use. Will look at 20s this time.

Nice. Like the wheels! Can you tell me what wheels those are and size? They do not look OEM?

Noticed the same thing for the last two years on test drives. Dealer needs to have some returns and write ups on this. Really doubt GM will move on the issue. But they have to have many dealer complaints filed to even be on their radar. Doubt the dealer will do anything. Not much they can do. This will be a job for a quality auto upholstery shop. Because of the seats and trans, I was so go on the 2017& 2018, now '19s. The seats where just hard and uncomfortable after 15 mins. I would spend the bucks to have it fixed. My '09 SLT buckets are great. Wife loves them. The new ones, no. Also noticed that on the newer trucks they removed the small amount of padding on the outside frame, where the seat back and bottom meet. Not a big deal, Unless one does not use steps. I'm 6'3" and just step in/out of the truck. Going out the unpadded frame rubs harshly on upper leg bone. If I get one I will have to have a good upholster address the issue and the hard seat. Lucky we have several in the big town of SA.

with AFM or DFM one has lifters continually pumping up/or collapsing. On the DFM the mechanics are more complex and a bigger chance for failure. Most folks cut off AFM/DFM to cut down on all this mechanical wear of on/off lifters etc...On the AFM, I read that GM said the gas savings from AFM was less than a mile per gallon. IF one drives in traffic with traffic lights etc... on a regular basis, the stop/start will/should save one more gas. My AFM is off. No stop/start yet but when I do get one, it will be disabled too. I agree, Just nice to have the option.

Maybe GM will have the bugs out of the new 3.0 diesel by then and offer it in the Sub. It Would be nice in an LT or LTZ.

Did yall watch the 14 minute engine vid walk through? If that does not strike one as complex, with a lot of valves and sensors and water flow here and there based on this and that, I do not know what will. As one that had the early model 5.3 with the new AFM issues, the 6.2 looks like the way to go for a few years at least. Edit: 6.2, even with the new DFM, still seems like a better choice. At least there will be a DFM deletion kit soon, should it give one issues after warranty.

Yep, agree. Seems way too complex. It has a lot of new this and that to pass EPA and get good mileage. Not a first year engine buy for sure. IF one gets one, one better get 100,000 mile power train wty. . 6.2 seems a better choice right now. .

Thank you for the work and post. Also glad for the tip that these dogs are just a bit wider. My 09 just makes it now. And the folding motors/gears are shot. Tip for those buying a truck and want something minor changed on it. My last truck, I wanted a different grille and door handles than the SLT came with. When getting a price on the truck, I said I'd take it if they sell me the grille and handles at their cost and install at no charge. They agreed and did such. So if there are a couple of things like those minor changes, get them agreed to in the deal. Of course this is a small town family owned and run dealership. You talk to the service manager on service major issues, as he is working the lane with the other two writers and techs.

Yes. My friends trail boss bed is a stretch for me and I'm 6'3" with long arms. He is normal height of about 5'9" and works wi see the bed floor with the gate up. I think he can just reach the floor. I can get in and out fine with out the use of steps. Him no. They do seem high, He says that even the non trail boss trucks are about 2 inches higher than the previous models????? I have not verified that . Yes they do seem tall even at 6'3". But I like it I think?

I forgot to add to my the DLC not that accurate for MPG post, that I always buy a truck and worry about MPG. Driving a brick down the road has to mean one is not or should not be concerned about MPG. Per my Dad, (RIP), How much rain did you get and MPG answers always require some skepticism. Computer or manual....