4-Inch Lift Kit with M1 Shocks for Silverado/Sierra 1500 4WD
- Fits 1999-2007 Chevy Silverado 1500 / GMC Sierra 1500 4WD and AWD, plus 1500 HD and Classic bodies — check the fitment list
- Does not fit 1999 old body style (OBS) trucks
- Includes two M1 Monotube shock pairs, front and rear kit boxes, crossmember, and driver/passenger knuckles
- Frame bracket and differential modification required; factory-painted bumpers need valance and bumper trimming
- New wheels must be 17 inches or larger on trucks with factory 17-inch wheels
The Trail Fortress check
Will it fit your truck?
✓ Fits
+ 5 more applications
✕ Does not fit
- 1999 old body style (OBS) models
Frame bracket and differential modification required. Models equipped with factory-painted bumpers will require trimming to the valance and bumper. For a visual please click here. If equipped with factory 17" wheels and purchasing new wheels the new wheels must be 17" or larger. For ease of installation a torsion bar removal tool is recommended 1067. Fitment on this page is based on the manufacturer’s application data.
About this kit
4-Inch Lift Kit with M1 Shocks, fitment-checked
Rough Country 25840 is a 4-inch lift kit for 1999-2007 Chevy Silverado 1500 and GMC Sierra 1500 4WD trucks, shipping with two pairs of M1 Monotube shocks, front and rear kit boxes, a no-transfer-case-drop crossmember, and driver and passenger knuckles. Frame bracket and differential modification are part of the job, and 1999 old body style (OBS) trucks are not covered.
This 4-inch lift kit for the 1999-2007 Chevy Silverado 1500 and GMC Sierra 1500 4WD also covers Silverado 1500 HD, Sierra 1500 HD, the Classic bodies, and the 1999 Chevy K1500 LS listed in the fitment section, including AWD and Auto Trac applications. Plan on frame bracket and differential modification; factory-painted bumpers need the valance and bumper trimmed. Trucks running factory 17-inch wheels must move to 17-inch or larger if new wheels are going on. Torsion bars stay in their original location, and a torsion bar removal tool makes the work easier.
What’s in the box
Kit contents
- 1× NTD Crossmember Kit Box 1272BOX7
- 1× Kit Box 1258BOX8
- 1× Dr & Ps Knuc 1285
- 1× GM 99-06 1500 4WD UNIVERSAL 4IN REAR KIT BOX 1258BOX9
- 1× M1 MONOTUBE SHOCK PAIR 770760P
- 1× M1 MONOTUBE SHOCK PAIR 770739P
Rough Country shares subassemblies across kits, so individual package labels can carry broader application ranges. The complete 25840 kit fits the vehicles shown in the fitment section above.
Specifications
Specs
| Brand | Rough Country |
| Part number | 25840 |
| UPC / GTIN | 00840269941498 |
| Lift height | 4 in |
| Shock package | M1 series |
| Shipping weight | 199 lb |
| Country of origin | US |
| Category | Suspension & Lift Kits › Lift Kits |
| Installation guide | Downloadable PDF |
Why buy here