Sierra — T1XX (2019–2026)

gas L4, SIDI, VVT, DOHC, aluminum; TurboMax is the name in the 2025–2026 guides ("Engine, TurboMax")

gas, direct injection, aluminum, Gen 5, variation 1

the upfitter lists: gas, direct injection, Dynamic Fuel Management, aluminum, Gen 5

the upfitter lists: gas, direct injection, Dynamic Fuel Management, aluminum, Gen 5

common rail injection, DOHC, VGT turbo, aluminum

gas, Gen 5, SIDI, VVT, OHV, E85 capable, aluminum

the upfitter lists: common rail injection, DOHC, VGT turbo, aluminum, variation 2

8L80, Gen 2, ATSS, CPA

10L80, GRX, Gen 1, ATSS, variation 1

10L80, GRX, Gen 1, ATSS, variation 1

10L80, GRX, Gen 1, variation 1 (no ATSS)

10L80, ATSS, CPA, Gen 2

10L80, ATSS, CPA, Gen 2

8L90, ATSS, CPA, Gen 1

HMD, 6L80

switch-activated, aluminum

switch-activated, aluminum

the upfitter lists read "Axle, positraction, limited slip"

the upfitter lists read "Axle, front, electronic locking differential, driver select"

the upfitter lists read "Axle, rear, electronic locking differential, driver select"

the 2025 and 2026 guides head this column Pro; NICB prints the base series as Fleet/Base through 2025 and PRO in 2026

the upfitter lists read "Package, SLE option 1"

the 2025 and 2026 guides head this column Elevation

the 2025 and 2026 guides head this column Elevation; NICB 2022 prints a 2021 Elevation (3VL) series

the upfitter lists read "Package, SLT option 1"

the 2025 and 2026 guides head this column AT4

the 2025 and 2026 guides head this column AT4X

the upfitter lists read "Package, Denali option 1"

the 2025 and 2026 guides head this column Denali Ultimate

the 2024–2025 lists print its contents under the code (high-capacity air cleaner, 220 amp generator, headlamp flasher, taillamp flasher calibrations, 110 volt instrument panel outlet, hitch guidelines, heavy-duty trailering provisions)

the 2024–2025 lists print its contents under the code (hitch view image adjustment, smart trailer integration indicator, universal garage door opener, premium branded audio, power rear sliding window, integrated trailer brake)

the 2024–2025 lists print its contents under the code (safety alert seat, front and rear park assist, rear cross traffic braking, rear pedestrian detection, enhanced side obstacle detection, HD 360 camera, trailer views)

the 2019–2023 lists read "Sales package, functional package"; the 2024–2025 lists print its contents under the code (rear window defogger, remote start, electrical theft deterrent)

the upfitter lists read "Sales package, style variation 1" and the 2024–2025 lists print a high-capacity air cleaner and "Off Road" sport skid plates under it

the 2024 list prints its contents under the code (front and rear park assist, rear cross traffic alert)

the 2024–2025 lists print its contents under the code (adaptive cruise control with stop/go, windshield head-up display, rear camera mirror, power tilt and telescoping steering column, cargo bed camera)

the upfitter lists read "Sales package, interior leather package"

the lists print "AT4 X"

the upfitter lists read "Performance package, enhanced towing"; the 2024–2025 lists print its contents under the code (limited-slip axle, 3.42 or 3.73 rear axle, integrated trailer brake)

dealer-installed

the upfitter lists read "Seat, rear, split, folding, base storage"

the 2025 upfitter list reads "Accessory, utility wall, front"

the upfitter lists read "Seat, rear, split, folding, deluxe storage"

the 2023–2025 upfitter lists print this code as a Chevrolet Bison sales package and are not cited for it

the 2019 list marks it not for use after model year 2022; the upfitter lists read "Camera, 270 degree and rear trailer view, HD digital"

the upfitter lists read "Provisions, snow plow prep"

the upfitter lists read "Sales package, appearance" and the 2024–2025 lists print its contents under the code

the 2024–2025 lists print its contents under the code (heated rear seats, universal garage door opener, power rear sliding window and others)

the upfitter lists read "Appearance package, GMC 'X31 Off Road'"

the 2020 list reads "Fuel economy, extra fuel economy"

the upfitter lists read "Chassis package, continuous damping control"

the upfitter lists read "Chassis package, high performance"

the upfitter lists read "Chassis package, 'Off Road' 2 inch lift"

the upfitter lists read "Trailer provisions, special equipment, heavy-duty"

the upfitter lists read "Chassis package, increased capacity"

the upfitter lists read "Sales package, convenience"

the upfitter lists read "Sales package, trailer integration"

the upfitter lists read "Sales package, LS fleet"

the 2024–2025 lists print heated front seats and a heated steering wheel under the code

the upfitter lists read "Chassis package, high performance lifted"

the 2019–2020 lists describe a 17 x 8 steel spare wheel, design 2 (SEO)

the upfitter lists read "Wheel, 18 x 8.5 J aluminum, design 13"

the upfitter lists read "Wheel, 18 x 8.5 J aluminum, design 14"

the 2019–2020 lists read "Key, single key system, 2 spare keys"

the 2019–2024 lists read "Accessory, brake upgrade package 1, complete"

the 2025–2026 guides name the RealTruck Advantage soft folding truck bed cover

SEO

the 2020 list reads "Provisions, rear camera prep and camera (SEO)"

the 2020 list reads "Seat center, front row 20%, center seat delete (SEO)"; the Silverado T1XX doc reads "Seats, front individual driver and passenger"

the 2019–2020 lists read "Tire and wheel, spare wheel and carrier, none (SEO)"

the upfitter lists read "Accessory, tailgate assist lighting"

the 2019–2020 lists read "265/70R17 SL 115S BW AT (SEO)"

SEO

the upfitter lists read "Equipment, accessory wiring junction block"

the upfitter lists describe the 8-way power adjuster (recline, fore/aft, height, tilt); the 2025–2026 guides count the lumbar as 10-way

the Silverado T1XX doc reads "Seats, front 40/20/40 split-bench"

the upfitter lists describe the 8-way power adjuster (recline, fore/aft, height, tilt); the 2025–2026 guides count the lumbar as 10-way

the upfitter lists read "Accessory, floor liner, contoured, alternate design 1"

the upfitter lists read "Accessory, floor liner, contoured, alternate design 2"

the Silverado T1XX doc reads "Seats, front 40/20/40 split-bench"

the upfitter lists read "Lock control, extended range passive entry, front doors"

front seat side and roof side airbags for driver and front passenger; the 2025–2026 guides add the front outboard passenger sensing system

the upfitter lists read "Seat, front split, driver, passenger, full feature center"

the upfitter lists read "Covering, front floor mats, auxiliary"

the upfitter lists read "Covering, rear floor mats, auxiliary"

the upfitter lists read "Covering, front floor mats, carpeted insert"

the upfitter lists read "Covering, rear floor mats, carpeted insert"

SEO

the 2025–2026 guides name them GMC MultiPro Power Steps

the upfitter lists read "Switch, engine start, keyless"

the Silverado T1XX doc reads "Air conditioning, single-zone manual"

the upfitter lists read "Vent, air, console, rear"

the upfitter lists read "HVAC system, air conditioner front, electronic controls"

the 2020 list adds "do not use next new major"

the upfitter lists read "Console, front compartment, floor, custom"

flat driver side, convex passenger side; the 2025–2026 guides add Black

flat driver side, convex passenger side

flat driver side, convex passenger side

the 2025–2026 guides read high gloss Black

the upfitter lists add wide field of view, manual-extending, manual-folding, heated, auxiliary cargo and clearance lamps

the upfitter lists add turn signal indicators, memory and auxiliary clearance and cargo lamps

the upfitter lists read "Mirror, inside rearview, light sensitive, full video display"

the upfitter lists read "Pickup box inner, alternate material"

the upfitter lists read "Body equipment, fleetside pickup box"

the upfitter lists read "Transmission range selector system, electronic"; the Silverado T1XX doc reads "Shifter, electronic transmission range selector"

dealer-installed; the upfitter lists read "Accessory, wheel, 18 x 8.0 J aluminum, design 2"

the upfitter lists read "Alert, safety haptic seat"

the upfitter lists read "Radio, infotainment system 3.x mid/high HMI, enhanced connectivity 2.0, voice recognition"

the upfitter lists read "Radio, infotainment system 3.x low HMI, midlevel connectivity 3.x"

the upfitter lists read "Brake system, power, front and rear disc, ABS, 17 inch"

the upfitter lists read "Air cleaner, high capacity"

the 2025 upfitter list reads "Air cleaner, performance"

the 2020 list marks it not for new or major programs (use KH8)

the upfitter lists read "Module, upfitter, serial data gateway"

the 2019 list prints no voltage

the 2020 list marks it not for the next new major program; the Silverado T1XX doc reads "USB ports, inside console with bucket seats or on instrument panel with bench seat"

the 2019 list reads "Port, electronic device, USB only"; the 2020 list reads "Receptacle, USB only" and marks it not for the next new major program

the 2020 list marks it not for the next new major program

the upfitter lists read "Steering wheel, synthetic, 4-spoke, thin, round"

the 2025–2026 guides name it the Super Cruise steering wheel; the upfitter lists read "Steering wheel, synthetic, 4-spoke, sport, round"

dealer-installed; the upfitter lists read "Accessory, rocker guard, tubular"

the 2020 list marks it not for the next new major program (use NC2)

the upfitter lists read "Steering wheel, standard"