thekcwolf

Yeah, It certainly blows having to keep your fingers crossed, so that you get to where you are going. Those knocking/metallic noises... I always had the understanding that was typical with these direct injection engines. Something about oil settling lower than in a non D.I. engine, so it would take a few minutes for the oil to warm up and get distributed around critical parts to at least quiet it down... (something like that), which would also explain the prominence on chilly mornings. Also probably why they suggest full synthetic oil. Well, anyway... Thanks to you as well for continuing to update your story. Aside from being able to learn a few things on these forums, it certainly eases the repair anxiety for the rest of us. Good Luck with all the new lifters, You should be okay. See you around ! Cheers, Tony

Dave, Having taken delivery of a '21 AT4 with the 5.3 and knowing the engine falls inside the affected date range of faulty lifters and rods and springs and rear window seals, I've been following here anxiously hoping your dilemma had been resolved. I can only continue to drive with fingers crossed. Not so, on the rear window. After 1500 miles and driving in various degrees of steady rain, for the first time... It leaks. I am right along side of you when you say you won't piss and moan and can only give you a "hang in there, man". I traded a completely reliable Titan with 110k of my own miles, because "I always wanted a Sierra". I even had a deal in the works for a new T, but... "I always wanted a Sierra". I am almost hesitant to ask if you happen to know the production date of the engine in your truck, because I shudder to think it was nearly the same date as mine. (Feb 4, 2021). Ahh well. Keep us posted... I'll be watching, and... Hang in there, Man.

Dayum, BDogg... I actually thought this thread went dead. I, for one, really appreciate your follow ups. Good Luck with this. I hope it works out.

Ok, Got my AT4. Got under there and got an image of that decal on the engine. I have been everywhere to try and "decode" the thing. Which one of these numbers represents the "julian" date? It's probably right in front of my eyes. Help is greatly appreciated. Thanks! L84 210360788 CU7 12685254 002127157 1110000000000X T1210361CU7X0788 EDIT: Found a Julian Date Converter that jives. Also discovered these tidbits. *I read somewhere the T1 at the start of that code was designation for the newer body style. "T1 Platform" which replaced the "K2 Platform". T= Assembly Plant code. Which i assume is Ft. Wayne in this case. (I thought Ft. Wayne was a "Z" in the VIN.) 1= "First Shift" 21036= Year(2021) - Day of year(36th)... so (Feb. 5, 2021) The rest, although I am interested to learn about, is sequence codes (according to the other post). Hopefully the "Valve Lifter Service Update #N212353840" was performed prior to delivery. Cheers, Tony

I've been in waiting since September. You'll be lucky to find one at MSRP. Basically they offer "incentives". Many dealerships place a "Market Adjustment" on top of the MSRP which you will also be lucky, to chisel them down on that cost, too. There's an article about GMC warning dealers of price gouging, but in this high demand market, you're bound to see some sort of price increase. I've seen dealers with prices on AT4's that have less options, stickered for what I'm waiting for which has all the options.

Holy Cow.... That's a lot of errors !! Did you take delivery before the microchip shortage thing began? I'm wondering if the "newly processed" chips were manufactured poorly. When was your build date? (I've been asking that a lot).

Yes, there's a TSB out there. According to a request from "[email protected]", this vehicle was in an intermediate delivery status in Ft. Wayne. I hope you're right and I'm also hoping the dealer has something that tells me the work was performed, because that would ease my concerns.

I'm more "concerned" about the fact, that this thing has been sitting around somewhere since February/March of last year and will STILL have these major engine problems !!

What Year/ Model/ Build date is your vehicle? Does it return to normal when disconnecting from Bluetooth?

@Sharon Davis, Please do, come back and let us know what happened. What was the build date of your 2020?

Hey Now !! @WeGone Where is this Decal/Label/Sticker located? It doesn't look to difficult to see from "open hood" view. Interesting to see when looking at a new vehicle that's on the lot. Thanks !

Comical ad campaign !! Walter seems to take direction well !! That actor played a detective character in "Dope Sick", on Hulu. Also does commercials for (I think), Sprint mobile.

The high demand and the fact that there is no "market adjustment" on the vehicle I am waiting for, makes me want sit tight on it. I've seen other MUCH LESS equipped AT4s on the Build and Price/ Dealer Locator pages, listed near or above what this guy quoted me. That "build date", tho... 2/21... It's 2/22 now !!

This is why I love these forums. here you have a group of folks that are all trying to decipher a circumstance with the sole reason of finding out much desired info for the greater good ! well done. I'm VERY curious to know how many "Valve Lifter Failures" there has been, in engines that have the Pulsar units installed. Is it still happening? A bit of background... My (potentially mine), '21 AT4, with, get this, a build date of 2/21... ***YIKES*** is supposed to be at the dealer by next week. It's a 5.3 with DFM and Auto Stop. Other than chip shortage issues, No idea why it has been sitting so long.

Yeesh, I love these forums, but I hate these forums. All this discussion about failed lifters and such, really make it difficult to want to go through with the purchase of this '21 I've been waiting on. Dealer says it will be here next Monday. I know, I know... Not every '21 will have these problems but ... I'm not the gambling type. I want to get in, start it up and go. period.