dgstarr63

2021 Silverado LTZ71, 5.3, 8 sp, 3.23, 4WD, Stock 18" wheels and tires. City mileage short trips 12 mpg, long trips in city 14-16 mpg. Highway - 22mpg at 60mph. Are sure your odometer is accurate after your modifications?

It should, but to be safe check with Foxwell.

Foxwell NT530 GM

My 2021 5.3 with DFM started with an occasional banging up front and then lifter noise. The next day I drove 5 miles to the dealer. During the drive I had various unrelated trouble codes on the instrument panel. During the last half mile all symptoms went away and I accelerated to 50 mph with no issues. When I got to the dealer they scanned the engine and said that a lifter had either failed or there was an injector failure. The service writer said he was pretty certain it was a lifter. They gave me a loaner and kept the truck. They called later and said one # 4 lifter had failed and bent a pushrod. All 16 lifters were replaced an one pushrod at no cost to me. If you still have a powertrain warranty, I would go to the dealer and get this diagnosed.

Nothing, its at the dealer having the lifters replaced.

Dealer tried, but GM will pay for only one bank of lifters. How long until the next failure?

I had voted no, but a lifter failed yesterday, so I need to change my vote to yes. 2021, 5.3, DFM, 9900 miles

Engines are built at Tonawanda, NY, regardless of where the truck is assembled.

no

I would like to see more readers vote to get an idea of how common this is on 1500 V8 trucks with AFM or DFM. My GM service manager says it is about 10%. I am not sure how accurate that is.

If you purchase any 5.3 or 6.2 with AFM or DFM you are gambling that you will not be one of the 10% ? that will have lifter failure. If you don't want to take the risk, buy a 2500 and you will get a Bullitt proof engine.

My 2015 and 2021 never go above 210 degrees. Take to dealer for warranty repair.

If your tongue weight is so much that you get sagging in the rear, you need a load equalizing hitch such as an Easy-Lift. Your owners manual should give you your tongue weight limit.

I had the Range on my 2015 5.3, 6 speed, AFM, worked great. I now have a 2021 5.3, 8 speed with DFM. I sent the Range to the manufacturer and they modified it for the new truck. It also works great. I have not experienced the rough shifts since the dealer replaced the valve body. I don't think the Range effects the shifts. I think the mileage is a little lower, but there is nothing else negative that I have noticed.

If you can't figure this out, you should not be working on a $50,000 truck just to save a few bucks. Have the dealer do it every 5000 miles. I have a 2021 Silverado and changing the oil is no more difficult than on my 1962 Impala.