todd308

I find it funny that they specifically state that one should not try to compare sounds between similar vehicles, they are clearly cutting off the "Well my buddy's 6.2 and the other 6.2 you have on the lot don't make this noise" that they have certainly been smacked around with. Translation: Sorry some of our vehicles sound like they came from the junkyard, and some don't, sorry you got a crappy one. It seems like all of these noises are due to engine spark being retarded. So the question is why are some of the same vehicles nearly silent doing this, and others sound like a squealing metal pig in heat? Better yet, certainly other manufacturers with auto-start/stop have faced the same issue but have found a way to do it quietly. The bulletin just reeks of "Yeah it's poor engineering and quality control on our part, but don't worry because it's "normal operation" that your $60k truck sounds like a $500 yugo.

It is sad this has been going on for years with no fix. The solution evidently is to only park or drive next to other 6.2 GM's so that you can share the embarrassment of the rattling/chirpping noise at start and downshift. You'd be amazed how many looks of "is your truck supposed to make that noise?" I get from cars next to me when the truck auto-starts on nice days. Neighbor has a new Ram and it's not without it's issues, but it sure sounds quiet when it starts with a much more deep exhaust note. Meanwhile mine sounds like it has a bunch of loose parts rattling around when it starts.

I believe the vehicle/manufacturing CARB/EPA rules/regulations make it much harder to produce an aftermarket replacement primary gasoline tank compared to diesel requiring a lot more certifications/testing. That's why you see lots of aftermarket options for diesel, but basically nothing for gas unless it's an auxiliary tank. No idea why, perhaps it's because gasoline is more flammable/explosive etc. You can of course use external auxiliary tanks to transfer gasoline from into your vehicle, they just can't directly feed the vehicle, again no idea why they differentiate, but they do. I think Transfer Flow just recently did a 58 gal gas tank for some of the big Ford Super Duty Gas pickups, evidently the first of it's kind to be approved, but it took almost 3 years, and I believe the cost of just the tank is pushing $3k. Maybe it paves the way for more options, but at $3k how many 1/2 ton guys are going to drop that for 30-34 gallon option. That's probably my entire fuel cost for a year, but if it's your work truck or you do a ton of towing, overlanding I could see where it might be worth it. GM should just pull their heads out and offer a larger tank option. There's plenty of room under the truck for a larger tank, 30+gal should be easy. The room from the Def tank alone is over 5 gallons.

As a further update it does appear to be due to the wiper arm itself, not the wiper blade. So when I replaced the wiper blade in spring it worked a bit better but not for long. Recently I replaced the wiper blade again (all wiper blades were the GM OEM version), it did not help, however when I replaced the wiper arm itself the issue is gone......for now. I can only conclude that somehow the wiper arm is losing spring, or getting bent during use etc. One other thing I did is you can "clock" the wiper arm a bit if you want to make it not sweep quite as far out (less windshield curve) so I adjusted it so it stops about 1/2" sooner, however even when clocked at the same position as the original arm it cured the streaking issue. Seems like the only answer is every spring to buy new OEM wipers, and a drivers replacement wiper arm for $15.

That's completely ridiculous, but not surprising, GM is clearly assuming you are a total idiot with such a response. While I'm sure many parts are different, It would be interesting to see if this happens with the 6.2 Camero/Corvette. The reality is unfortunately these noises seem "normal" for this Truck/Engine, however it's NOT normal for a new vehicle, and it doesn't change the fact that it sounds like it belongs in a junkyard when it cold starts, restarts at stop lights, and downshifts.

Not sure, but prices are going up, ZR2 MSRP for 23' is going up another $1500 over what's currently on the web page for a 22' ZR2

Yep, it sounds like they plan to remove it being a line item and just include it onto the MSRP so people stop realizing they are charging them $900-$1700 for an onStar subscription depending on model. Brilliant by GM, can't get people to pay you $50 a month for onStar, just make it a mandatory option.

Yep that sounds like it, mine has a little more "flutter" to it, but same thing, goes away after 20-30 seconds, but you can also hear it for a few seconds after a restart at a stop light, and if you are driving say in an alley or along a building you can hear it doing it when the truck downshifts at low speeds. I believe it has to be DFM related, if I run the truck in L-9 it goes away when shifting (it won't auto start/stop in L-9 so no testing that or cold startup). It's also probably why GM can't/won't do anything about it and simply considers it "Normal Operation"

Yeah it will probably just have to wait till it gets worse, or the AC fails. It's too intermittent unfortunately at this point to guarantee I can duplicate it with a ride along. It might only happen every 3-5 times I drive the truck, and even then only when the truck is first restarted cold initially when it's first being driven for say the first 10-15 minutes of city driving, won't ever do it on the highway.

I've noticed that sometimes driving my 21' AT4 6.2 that especially if it's hot leaving work for the day that when slowing down like coming to a stop light etc. the AC appears to shut off, the air still flows but you can feel that it gets warmer (not hot) and gets humid/musty smelling. Very similar to what it does when it would auto-off at a stop light, except the vehicle is still running. It also seems to stop doing it after driving for awhile and when just driving say on the highway I haven't noticed it happening. The problem is it doesn't do it all of the time, I had my dealer look at it, but they just said they could not replicate the issue. My 20' AT4 definitely didn't do this and overall I think it blew colder air. Just curious if anyone else has noticed similar and gotten anywhere with a dealer on it? Thanks

I don't think that's quite how it works, a linear rate spring only means the spring rate increases evenly throughout it's travel, it doesn't mean that the spring has the same force throughout it's travel. So if you crank up the preload and raise the front end height it's going to stiffen the ride. The plus side is usually the aftermarket shocks (fox, billstein) are so much better than Rancho's no one notices, especially if you get the strut with the fox/bilstein matched springs. This is why strut spacers tend to maintain a factory ride better than height adjustable struts. That said, there are some other significant cons to spacers if your vehicle actually leaves the pavement and overall I'd say the adjustable height struts are a better option, of course they are also significantly more expensive, especially if you don't reuse the factory coil springs. This site does a very good job of breaking down the pros/cons of spacers -vs- height adjustable struts. https://www.shocksurplus.com/pages/lifted-and-leveling-struts-vs-strut-spacers

Should you still do new UCA's with the shock based "lift" to avoid UCA failure like we see with many level kits when people don't replace the factory UCA's? I'm guessing not since all it's doing is adding spring preload stiffening the ride to get the extra height as opposed to a spacer lift.

Yep, GM just shoves some sealant in there hoping it gets you to 3/36, so then the correct fix is on your dime. If it was me, considering what GM probably wants for a repair, there's some good threads here and videos on how to do it yourself. I'd probably take that route if I was out of warranty on my 21'. Partly because I'm pretty sure I'll do a better more considerate/cleaner job than I've seen dealers do. The job the dealer did on my 20' with a rear window leak looked like they let a 3 year old use it for finger painting practice with sealant. I also agree on the extended warranties if you keep a vehicle past the warranty and don't drive a huge chunk of miles. As long as you do your homework and make sure if it's not GM it's a reputable company. These days everything is so ridiculously expensive it's not hard to recoup $2k. I'd imagine since a dealer charges $1200 for a headlight for one of these trucks, that by the time they replace it, you're not far off $2k.

That's pretty sneaky of GM, people won't pay them $50 a month for onstar so they just force 3 years of it onto the vehicle options/fees. I guess at least you get it for $25 a month instead.

The reason they don't let you roll up remotely, is the same reason you can auto-down all 4 from the drivers door with one momentary press, and one momentary touch upward will auto close the front windows but you have to hold the rear window switches up to get them to come up. It's liability, they don't want you closing the window on something or someone you didn't see. Which is a little odd, because as many who have installed in-channel vents can attest if the window senses much friction it goes back down, but I'd imagine it's still enough force to do some nasty damage to say a kids finger, or a pets nose/ear. I don't think I have the big center infotainment button I think that's where the descent control is, though I always thought it was funny that the button is so huge, they could have put 3 buttons there.