According to GMFleetOrderGuide, the following powertrain changes are slated for model year 2022 (to date; a carry-over of the '21s).

• 4.3L EcoTec3 V6 (LV3) : discontinued
• 5.3L EcoTec3 V6 (L82) : discontinued
• E85 FlexFuel (FHS) : discontinued
• 6-spd HydraMatic (MYC) : discontinued

> 2.7L Turbo I4 (L3B) : standard on Silverado WT, Custom, Custom Trail Boss / Sierra 1SA
> 5.3L EcoTec3 (L84) : standard on Silverado RST Crew Cab / optional on Sierra 1SA
> 5.3L EcoTec3 (L84) : optional on Silverado WT / discontinued on Sierra AT4
> 3.0L Duramax I6 (LM2) : optional on Silverado LT Trail Boss / standard on Sierra AT4

Edited August 31, 20214 yr by balthazar

Trailboss is diesel standard and turbo4 optional with no V8? Or is the 6.2 still there and just not a change?

No...
These are changes for '22. Don't forget- there are 2 Trail Bosses- Custom line & LT line.

In '21, Custom 'Boss can come with the 4.3L/6-spd, 5.3L/6-spd or 6.2L/10-spd.
LT 'Boss can come with 5.3L/10-spd or 6.2L/10-spd.

For '22, the 4.3L is gone, and the 2.7L & 3.0L DM are added to the Custom 'Boss, and the 3.0L DM is added to the LT 'Boss. 

- - - - -
GM really doesn't have (the trucks at least) set up as 'standard' and 'optional', except the prices to increase as the engines 'go up'. Same thing... mostly.

In '21, an LT 'Boss 5.3L CC/5.5' bed starts at 53,195, and going to the 6.2 the price rises $2425.

In the '21 RST, the 2.7L starts at 48,895.
Going to the 5.3L raises the price by $1325.
Going to the 3.0L DM the price rises $2370 (over the 2.7L)
Going to the 6.2L the price rises $3820 (over the 2.7L)
 

Interesting, course the Diesel engines are offline due to the chip shortage, so right now none being built.

Understandable that they would simplify their order guide, but I do have to wonder how the next 12 to 18 months will play out as they work on their BEV's and still try to build and sell auto's.

Many of us do not care for the auto start/stop or cylinder deactivation, so having those pulled for the 2022 year till chip supply gets going again, I doubt will be missed, but I do have to wonder about other things that go away for now due to the chip shortage.

GM-sourced info says the expectation for the diesel line to start again is December.

As GM is relatively dedicated to the turbodiesels, I expect them to continue the longest in the IC fleet. The MPG certainly helps the Corp numbers, and the consumer demand is very strong for them.