2017 1500 High Country

[aotte1]

Purchased a 2017 1500 High Country with 5.3 engine, crew cab, short bed.
Initial reaction is not good, several small problems now at 1800 miles, along with not liking drive train. Not sure what is going on with engine and trans. Engine seams to not have power, and towing 5K lbs. is a real struggle. No way it has HP and torque they say. Will hardly accelerate, when you use half to three quarter throttle, engine rpm goes to 5000, trans seems to have big time converter slippage as truck only accelerates maybe a few additional MPH when going 45 MPH. This new trans/converter seams to not function well. It needs lots of RPMs to accelerate from a stop, again converter seams to slip a lot. Needs 2000 RPMs from a stop vs. my 2010 5.3/6 speed auto needing only 1200 to 1300 RPMs, for same rate of acceleration. The trans also makes a very HARD clunk when shifting sometimes, at light loads/acceleration.
Small problems; 1) complete windshield washer system needed replaced, 2). Outside Temperature reading not working, 3). Lane change alert system stopped working, 4). Bed lights not working, and 5). Rear back up monitor in cab is very faint, hard to see.

Very disappointed in this truck, would not buy again, overall seams extremely cheap.

Recommendation, do not buy the 5.3 engine, they have ruined it, maybe 6.2 is better? It is possible the 8 speed trans is pure junk, vs engine.

Have always been Chevrolet person, first was a 68' Camaro SS/RS 396, followed
by at least 30 other new GM vehicles. Current vehicles are 2010 1/2 ton Silverado - great truck, 2014 GMC Acadia - nice vehicle, 2012 Corvette GS-CE outstanding vehicle!! And collection of 65 and 66' trucks.

Friend has similar 2017 LTZ and it has ALL the same engine/trans problems.
Know vehicles a little as race NHRA "C" stock automatic, 70' GS 455 stage 1.

[4x4k30]

I would take it back to the dealership if they check it and say they cant find any problems I would take it a mechanic that you can trust and have them check it out or find another dealership I know how it is with warranty work it sits there until they want to get to it the other big paying jobs come first. it does sound like you have a lemon the truck should do better than your 2010 does good luck

[aotte1]

4x4 thanks for reply.

Also forgot to mention that both front doors are rusting after owning six weeks, in sunny Kentucky. No winter, no salt. Will post pictures soon. The rust is the seam where the two door half are welded. The seam sealer used, has cracked and let water. It is rusting uncoated metal. The rust is coming out the crack and staining the door jam paint. Thought GM was using metal body panels that have a rust protective coating, befor being painted. Guess not anymore, new six week old track and door jam is rusting. Again this is summer/fall with only rain?

[aotte1]

Door jam photos, at 6 weeks.

[4x4k30]

dang they must have sold you a new truck that they ran the water spray test on to for too long and that looks bad I cant believe that gmc trucks are getting that bad my 77 gmc is 40 years old and does not have any problems like your does I would check on the lemon law in your state and demand your money back .

[aotte1]

Discussed these issues with very knowledgeable person on GM trucks, and he has same option on this 2017 power train. He has driven the 2017.
I am now hoping, GM will write new control program for trans and engine.

A good thing is it can gets crazy good mileage on the highway, high for Z71 is 26.2mpg and High Country is 25.2 mpg. Even at plus 70 going up and down hills with load in bed 21mpg. Going up mountain On I64 in West Virginia the Z71with around 1500 lbs. in truck it got around 19 mpg. Their are several good things on these trucks, however, powertrain is not one of them, except for mpg on highway.

The bad thing is not knowing which gear it wants to be in, loud clunking sometime when it shifts, converter slippage on starting from stop and down shifting at WOT or 3/4.
The truck does not accelerate well under WOT or 3/4. Has very little towing power.

The rated HP/Torque is not showing up, for some reason. With this much SAE rated HP it should accelerate pretty quick, it does not. With E85 fuel this is supposed to make 395 to 400 HP per GM Powertrain Division documents on the web.

Option, in may ways, for very technical/knowledgeable person, it is not fun to drive.

[aotte1]

The two 2017 trucks, Z71 and High Country. No, not on side of mountain in West Viriginia, held IPhone wrong way and forgot to edit photo.

[72Cheyenne454]

I can relate to some of these issues and experienced a multitude of issues with a new 2015 GMC Sierra 1500 (6.2/8speed/4wd) that I bought new in Aug of 2015. I was so disappointed in the truck and the numerous issues it started having right after purchasing it that it made me sick to my stomach. Ultimately, after multiple attempts at the dealer to solve these issues, I traded the truck in with only 4k miles on it and purchased my wife a new car. What a major disappointment and a financial loss. I've always been pro GM, but this truck was a major let down and I got so sick of GM saying "it's normal", or "could not duplicate". Ugh.

Some of the issues I experienced were...

Engine rattled on cold start - like lifter clatter, only for a split second, happened every cold start
Random clunking/banging from the transmission while down shifting. Banged so hard sometimes my wife thought we had been rear ended
Random popping noises coming from the dashboard near the windshield as the temperature changed inside the truck
Drivers seat squeaked
Wind noise from both front doors - actually whistled while on the freeway
Rear rubber brake line to caliper leaking
Both rear factory Rancho shocks leaked oil
Runs in the clear coat on the bottom of the doors

I wish you luck with your truck.

[aotte1]

Some of the issues have gotten better, they are:
- torque converter/transmission shift point, much better at 2800 miles. It will now upshift gears at 1200 RPMs, and converter seems to lock up at much lower RPMs. This change occurred around 2500 miles. Not sure why??? Transmission computer program came new stupid and needs to learn?, safety programmed to not load engine when new?, other??? It shift points now nice, versus new awful.
-gas mileage, a little more outstanding, as good as 28 mpg.

Still bad:
- the transmission or rear end hard clunk randomly . I mean hard, worse then my 1070 NHRA stocker race car. The two 2017 we have both do it, bad! May only do it under light acceleration in lower gears, low speed. Does it both upshifting and down shifting.
- WOT acceleration is disappointing, for rated HP, it seems weak, and does not know which trans gear to be in, and not giving you full power. Accelerates quicker and stronger at only 3/4 throttle. Our 2010 feels much faster by a lot. HP rating seam weak for towing too. Have not done much, only 5K lbs. If towing some, would recommend considering the 6.2 engine. Did not drive a 6.2, so can not say for sure if a good choice.

Overall option still out, wife really likes it, first Truck she has liked. Want to take it all the time.

Will update more in a few months. Have 2800 miles on it at 8 months. For me it is the last vehicle I choose to drive. Choose first the: Corvette, 2010 Silverado, 2015 Acadia ( starting to like it more- sure wish it had a V8), before 2017 Silverado Crew Cab.

[Prong]

If you have the 8 speed trans, there's a programming update for that to reduce the bang shifts. I believe the tsb# is 16-na-411. I had it done to my 15 and it corrected 98% of the troubles.

[LEEVON]

The 8-speed is a different animal, I hope they can help you. Be glad you didn't buy the factory vibration that GM has no clue how to fix. My 17 Sierra has been somewhat disappointing and is about to get the boot before 3,000 miles. I can't stand the vibration and there is no fix in sight. I also have a bad shudder on deceleration and the cabin is so cramped. Also my seat is already wrinkling on the outer edge and it's not comfortable, I feel like I'm sitting on a fat wallet on each butt cheek. And I'm sitting completely upright, it's got less room than any regular cab I've owned from the 40's and up.

I am very jealous of your mileage, I'm at 15.6 combined highway/city and it's a regular cab 2wd 5.3/6 speed. It should do much better, otherwise why do I have to have all of this direct injection? Make sure you're getting all of this documented!

[Hart_Rod]

Originally Posted by Prong

If you have the 8 speed trans, there's a programming update for that to reduce the bang shifts. I believe the tsb# is 16-na-411. I had it done to my 15 and it corrected 98% of the troubles.

Is that for all years?

[Prong]

If you google that GM TSB#, it gives a list of what it covers. I believe there's also a reference in the document to other years that the update may apply.