losky79

That is a good looking Tundra, by far the most reliable truck on the market. I took my 21' AT4 to CarMax and they offered me more than I paid for it, so it was an easy decision to dump it right away. Hopefully GM gets this problem figured out, they have a winning combo with the 3.0 Duramax and the 10 speed trans. But for now, it's not my problem anymore!

GM has just stopped production of the 3.0 Duramax. They say it’s due to a supplier shortage. I call BS, they stopped production to figure out what’s going on with these engines. https://tfltruck.com/2021/08/breaking-news-gm-is-stopping-production-of-the-3-0-liter-duramax-diesel-i6-engine-due-to-a-sudden-supplier-shortage/

Hello all, its been awhile since I have visited this site. Anyway, I am back and I currently own a 2021 Sierra 1500 AT4 (3.0 Duramax). Let me just say, I bought F150's for the last 8 years and this truck is absolutely amazing. The 3.0 Duramax with the 10 speed transmission drives and shifts so smooth. GMC knocked it out of the park with this combo. Now to the bad news, I too am having starting problems like everyone else. I purchased my truck in March of 2021 and it's build date was also in March of 2021. It was built in Mexico based of the VIN. I have had the no start problem 3 times since I purchased the truck. The first two happened before I hit 1000 miles and the third one happened yesterday (8/6/21) at about 5300 miles. I have not taken it to the dealer, because based off reading these posts and prior knowledge of how a service departments work, I knew there would be no reason. If they can't duplicate it, or get a "Code" then it's pretty much useless to take it to the dealer. So after yesterdays (8/6/21) no start incident, I decided to contact GMC via their Customer Service Text Chat line this morning (8/7/21). I basically only wanted to let them know, my truck was having the no start issue like many others here and across the country, even Canada. While chatting with the GMC rep, they stated that On-Star was showing my truck threw Code P0234 yesterday, even though I did not receive a check engine light. I don't know if that will cause the vehicle not to start, but it might help us in figuring this no start problem out! According to Google, P0234 is a Diagnostic trouble code (DTC) P0234 stands for “Turbocharger/Supercharger “A” Overboost Condition.” It is logged once your vehicle's powertrain control module (PCM) perceives that the boost pressure in the forced induction system is too high or beyond the manufacturer-specified limit.

Thank you, I kinda figured that's where it would be but just had to make sure. I ordered the relay for my HID kit and thanks to everybody's information I should have everything I need and hopefully everything will go well when I install it.

Where is the "inline" fuse located?

Agreed, going to swap mine out for the 4600's when they become available!!!

http://www.gm-trucks.com/forums/topic/153020-exhaust-adaptive-valve/ A quick way to find out if it is the exhaust valve located behind the rear of the muffler is to place a hose clamp over it in the open position then drive your truck and see if it still makes the noise you are hearing.

285/60R20's will work but the 305's will rub with just a leveling kit.

I have been searching for months for a CAI for the 4.3. Anybody know if they are available yet, I really don't care who the manufacture is.

On my 4.3 I feel a quick vibration throughout the entire truck when switching from V4 to V6 mode driving in the city, although I never feel it while on the highway or interstate. It only happens when I am driving between 30-40 mph at about 1000-1500 RPM. Is there a way to just deactivate AFM completely?

When my truck was bone stock I was averaging 19 city and 23 hwy. Keep in mind I drive like an old lady, so that helps with MPG. I do have the V6 and I am happy with it. I guess the only thing I have to get used to, is the sound of Direct Injection at idle. Is it me or do these new engines idle louder than normal?