tjonesdfw

I already own the 2021 Sierra Denali I'm debating taking well past 100,000. Shoulda, coulda, woulda bought a 2020 Tundra with the 5.7 instead of this if not for Covid era dealer shenanigans. Overall disappointed with the LONG list of non maintenance repairs this truck has required.... thank God for a 7 year 100K GM extended warranty that MORE than paid for itself. I find myself missing the reliability of my '97 GMT400 with the 5.0 Vortec that only seemed to eat the occasional alternator that I could replace in the NAPA parking lot.

Definitely monitoring the suspension. Was surprised a pavement pounder Denali with stock tires ate lower ball joints at 65K. The rear leaf spring isolator pads have also all been replaced TWICE!. Questioning wheel bearings, input output seals, coolant and oil hoses, and how long the electric adaptive ride control shocks will hang in there... already investigating the kits that eliminate those so I can use regular shocks without triggering a warning light. U-joints are on the monitor list as I already would have replaced them on an older truck. I think oner front CV is starting to make some minor noise, so that's the next repair. Just did the serpentine belt again when replacing a leaking radiator, and everything on the accessory drive looked good, but I wonder how much longer the water pump and other items will last. Battery gets replaced every 2.5 years regardless of how it tests. Otherwise everything in the severe maintenance schedule has been done religiously, along with a TON of other warranty repairs.

I am just trying to ascertain what common issues creep up over 100,000 miles on this generation of truck. I don't need any dealer help, and I'm well aware that some people don't consider 100,000 miles to be "high mileage," and I'm also aware that older generations of trucks had less major issues over 100,000 miles. The GM maintenance guide only goes to 150,000 miles and only references basic maintenance, not proactive replacement of things like gaskets, seals, bearings, etc. In my limited experience, I know multiple people who have lost transmissions and lifters shortly after 100,000 miles, so I was hoping I might get a consensus here from a larger sample of people. When driving nearly 20,000 miles a year, often in very remote areas, I personally prefer to be proactive.

I'm approaching 100,000 miles on my '21 with a 5.3, and despite all the electrical gremlins, ball joints/lower control arms that only lasted 65K miles, and a bad radiator.... the motor and transmission are still going strong. What are the common issues other than transmission and lifters people are seeing around 100K and up? Do wheel bearings and seals start failing, are the screens in the dash going to self destruct after so many years, etc.? Contemplating whether its worth keeping the devil I do know vs a devil I don't, especially considering the '27s are still not out. Ideally I'd usually wait a year or two after a re-design to purchase. Are there preventative maintenance procedures like replacing the torque converter, rebuilding the 10 speed, hoses, seals, bearings, and or a true DOD delete that would buy me another year or two of reliability with this heap? Driving 15-20K miles a year at the moment and need it to be as reliable as possible. I see some guys with over 150,000 doing just fine, and others have had transmissions and lifters go within months of getting to 100,000.

Pretty pathetic durability for ball joints on a half ton truck if you ask me. I spend most days on a smooth tollway or interstate, and spent very little time on gravel and chip and seal roads before mine failed. Then to have to replace the arms because they didn't make the ball joint serviceable is just icing on the cake.

I had the lower ball joints go bad before I hit 65,000 miles on a stock height, stock tire and wheel, no spacer, '21 Denali 4x4 that's almost 100% pavement driven. I think they billed my extended warranty about $3,600 for the repair, which was nuts. I also find it crazy that GM has dealers replace the entire lower control arm instead of having a more serviceable ball joint mount.

The waterfall sound is typically just created by air pockets in the heater core, cased by low coolant, not a leak inside the cab. From what I’ve seen, most of these radiators fail at the plastic end caps and seams, so check there first.

Ended up being a seep in the stupid plastic end cap on the radiator, so new radiator it is. 4 years and 70,000 miles and she's already needed 4 camera modules, multiple cameras and wiring harnesses, a new rear sliding window, ball joints and now a radiator among various other little items... not looking forward to the next year or two at this rate.

Back to another dealer next week with the same issue again... waterfall sound at startup, about an inch low in the tank, and the smell of coolant around the front of the truck every time I stop. Hoping this new dealer properly diagnoses, because in my mind there has to be a small leak somewhere.

More front biased than rear. Parking brake is always disengaged.

Been down this road before too and seems it repeats itself every 12 months or so. The first time the dealer pressure tested it twice... the first time it leaked down, and the second time it held, so they just topped it off and sent me on my way. Sending it back to the dealer this week for them to do the same since I'm under an extended warranty, but its down about an inch again and the waterfall sound in the dash at startup is back. Every time I stop and get out, you can smell antifreeze around the front end, but there's no visible signs of a leak.

Every morning immediately after the first cold start of the day, and after putting the truck in gear and letting fully off the brake, I get about 3 or 4 loud rotational rubbing metallic humming sounds that closely match ground speed, i.e. one sound per complete tire revolution. It initially sounded like a brake shield rubbing, but have checked those, and it doesn't make sense that the noise stops after the initial roll off and or the truck is warmed up. Truck is a '21 1500 4x4, and it makes the same sound whether in 2x4 or Auto. Bearings, CV joint, transmission/transfer case, any thoughts?

Have had the same issue in our 2021 Denali for years. Had the rear window re-seal TSB performed once, and recently had the entire power rear sliding window replaced, and it still smells like this after rain. Condensate line doesn't appear to be plugged, and not finding wet carpet anywhere either. Clearly something is collecting water and allowing it to sit though.

I clamped the flapper open today and also tried the resonator screen mod. So far it sounds ALOT better… no more rattle, clank, or chirp. It’s a touch louder on cold start and at low speeds, but no drone or flutter yet. We don’t have a Range device installed either.

Has anyone had loose or sheared alignment pins on a '19-'25? Just had new lower control arms installed under warranty for failing lower ball joints. After repair, dealer claimed several alignment pins were loose and they need to be welded back to the frame for some ridiculous price. Others say a good tech can align with a punch in the hole, and then torque the bolts properly. Has anyone here had an issue with this and repaired at the dealer or with any of the aftermarket solutions?

It was definitely the lower ball joints. Still surprised those failed at 65,000 on a pavement driven Denali without a lift or level and stock tires. When I picked it up, they said 2 of the alignment pins had "come apart from the frame and were loose." They recommended having them re-welded to the frame. Is that really necessary, or is there another way to repair?

Thats what I wondered too, but can’t get very good info from the dealer. Do these trucks eat lower ball joints this quickly?

Same here. Every time we went to this particular dealership, we picked up the truck with something else broken. Our first window repair was horrible as well. There was sealant all over the glass and spoiler, they broke one coat hook and mangled the other when dropping the headliner and just left them for us to find at pickup, and left greasy handprints all over the headliner. I swear a child could have done a better job... its almost like they TRIED to make a mess.

Has anyone here had their slider continue to leak AFTER the TSB sealing by a dealer? Fighting GM about the cost of a replacement slider now that its leaking again since they've already worked on it once before.

Agreed... absolutely everything seems designed to fail and be disposable. I'm not sure if they've manufactured the lower control arm to be unserviceable now, or if the book just tells the dealer its easier and faster to replace the arms instead of pressing bushings out and in. I was shocked at the $2,300 price to replace two control arms too. Guess I just got my money's worth from my GMPP warranty. Unfortunately the extended warranty won't pay for the other $4,000+ worth of repairs this pile of junk needs.

Have been driving a 2022 Silverado 1500 loaner while my 2021 camera system gets diagnosed, and the 2022 loaner is flashing to a black screen with a red exclamation in reverse. Had to just laugh... clearly GM is lost on this one!

I've tried clamping it open and it still rattles. I've heard a few straight pipe videos, but they all left the flapper in ahead of the straight pipe. Did you remove the flapper AND straight pipe on any with a 5.3? Hate to get it too loud and end up with drone as much as I drive on the highway. Still under a GM extended warranty and know several guys who've had issues with the Range OBDII devices causing other problems.

I haven’t really seen it anywhere either other than one mention by a user here in an unrelated topic, saying he had front end bushings go out really early. The dealer says it’s rare but they have seen it a few times. I still can’t get a clear answer from the advisor whether it’s the lower ball joints or the actual bushings. Either way, to have visible play in them at approximately 65,000 miles still seems unacceptable, especially for a 1/2 ton truck that’s not abused or worked hard. Not exactly confidence inspiring and adds to a very long list of warranty issues we’ve had.

Dealer says the leaf spring inserts have started to disintegrate and fail on our 1500 Denali. It squeaks pretty badly going over speed humps, with any flex, and even when stepping on and off the tailgate or rear bumper... all worse when cold. Unfortunately, they want $620 to replace them all which sounds excessive. They say the original parts were not lifetime warrantied, but the replacement parts carry a LLPW. Has anyone else had these go bad?

Dealer says the lower control arm bushings are shot on both sides of our 1500 Denali, with visible play at approximately 65,000 miles. Truck has rarely seen some VERY light dirt and or gravel road use, but is primarily highway driven. No lift, level, and factory size/rated tires. Thankfully the GMPP warranty is covering the $2,300 repair, but can't believe bushings are shot this soon. Is this common on '19-'25 trucks?