ReadyLift Off Road
2019-2026 GMC AT4 And Chevy Trail Boss - 1.75'' Leveling Kit
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Match the year, make, model, trim and engine in the product details. Review mounting requirements and vehicle modifications. Ask us about this part.
ReadyLIFT customers have asked for it and we have delivered. In fall of 2018 we announced our new leveling and SST lift kit offerings for the all-new GM 1500 trucks. We specifically did not include the factory lift kit-equipped GMC AT4 and Chevy Silverado Trail Boss. The AT4/Trail Boss are factory equipped with a 2" front lift. This front lift includes a longer front shock/strut assembly. When combining a traditional leveling kit on these factory lifted trucks, several issues present themselves including binding problems with the factory control arm ball joint and contact concerns with the lower strut/CV axle assembly. The ReadyLIFT 66-3921 1.75" leveling kit is similar to our popular 66-3086 leveling kit for pre-2019 trucks. The 66-3921 leveling kit provides required amount of lift without causing conflict with the factory strut geometry and clearances. In light of the factory upper control arm's lack of dynamic range when the AT4/Trail Boss truck is further lifted, this leveling kit includes our popular tubular upper control arms with corrected ball joint cup angles, heavy-duty replaceable ball joints and out new Terrain Control Technology (TCT) maintenance-free pivot bushings with side-biter washers to improve alignment retention. Note: AT4 and Trail Boss do not fit the same size tire. This is due to the difference in front fender opening design. NOTE: Not compatible with Sierra AT4X or Silverado ZR2 Edition. 66-3921 Leveling Kit: AT4 - Max tire 275/60-20, 20x9 0 offset wheel Trail Boss - Max tire 295/65-20, 20x9 0 offset wheel
- 1.75" front leveling lift
- Compatible with 20192026 GM AT4 and Trail Boss models
- Not compatible with Sierra AT4X or Silverado ZR2 Edition
- Includes DOM tube steel upper control arms
- TCT maintenancefree pivot bushings
- 1ton ball joints
- CNC machined aircraftgrade billet Aluminum top and bottom strut spacers
- AT4 Max tire size: 275/6020
- AT4 Max wheel size: 20x9 with 0 offset
- Trail Boss Max tire size: 295/6520
- Trail Boss Max wheel size: 20x9 with 0 offset
- Compatible with 2019 Compatible with 20192026 GM AT4 and Trail Boss models
- TCT maintenance TCT maintenancefree pivot bushings
- 11ton ball joints
- CNC machined aircraft CNC machined aircraftgrade billet Aluminum top and bottom strut spacers
- AT4 AT4 Max tire size: 275/6020
- AT4 AT4 Max wheel size: 20x9 with 0 offset
- Trail Boss Trail Boss Max tire size: 295/6520
- Trail Boss Trail Boss Max wheel size: 20x9 with 0 offset"
Specifications
- California Proposition 65: WARNING: This product can expose you to chemicals including Di(2-ethylhexyl)phthalate (DEHP), which is known to the State of California to cause cancer, and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov/product.
- Fitment: Direct Fitment
- Front Lift Component: Spacer
- Front Lift Height: 1.75 Inches
- Front or Rear: Front
- Install Difficulty: Difficult Requires Professional Installation
- Installation Time: 4 Hours
- Max Tire Size: 295
- Prop65 Chem1: Di(2-ethylhexyl)phthalate (DEHP)
Vehicle application overview
Confirm trim, engine, and installation requirements before ordering.
- 2019–2026 Chevrolet Silverado 1500
- 2019–2026 GMC Sierra 1500
- 2024–2026 Chevrolet Silverado 1500
- 2024–2026 GMC Sierra 1500
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Manufacturer & part identification
ReadyLift Off Road
| Option | SKU / part reference |
|---|---|
| Standard | 66-3921 |
Vehicle compatibility
Read the application years, model, trim, engine and exclusions in the description above. A make-level collection or product recommendation alone does not confirm fitment.
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Review the manufacturer’s specifications and installation notes above. Confirm required mounting hardware, tools and modifications before ordering. If instructions are not supplied, contact us with the part reference.
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