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Will 40-inch tires fit a YJ Wrangler with a 4-inch lift?
Fitment answer · Updated October 27, 2026
Short answer
No. 40s are far too big for a YJ Wrangler with a 4-inch lift; they hit the fenders, frame and steering. YJ owners on 40s usually run a spring-over or 6+ inch build with tube fenders and 1-ton axles. Very few YJs run 40s.
Shop the gear for this build ↓ Tires, deflators and a compressor picked for this setup.
What you usually need
- A spring-over or 6+ inch build with tube fenders and 1-ton axles.
- Major fender cutting or flat fenders.
- Axle upgrades.
- Low-backspacing wheels.
Regearing
40s call for 5.13 or 5.38 gears or lower. Compare ratios in the Tire & Gear Calculator before you buy gears.
Compare
Gear for this build
- Mud-terrain tires (search) — Louder on the highway; buy for real mud use.
- Staun tire deflators — Repeatable trail pressures.
- VIAIR 88P portable compressor — Air back up before the highway.
- YUNPEAK 1.26" × 30' kinetic recovery rope — Bigger tires, bigger trails: carry recovery gear.
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FAQ
Do 40s fit a YJ Wrangler with a 4-inch lift?
No.
What lift does a YJ need for 40s?
Usually a spring-over or 6+ inch build with tube fenders and 1-ton axles.
Do I need to regear?
40s call for 5.13 or 5.38 gears or lower.
Check your numbers
Use the free Tire & Gear Calculator to see speedometer error, highway RPM and a regear target, or ask TekJeep AI on the homepage with your year, trim, lift and wheel specs.
Related guides: All-terrain & mud-terrain tires · JK 2.5" lift overview
More fitment answers: 33s on a YJ Wrangler · 35s on a YJ Wrangler · 31s on a stock YJ · 33s on a 2" YJ · 35s on a 4" YJ · 33s on a 4" YJ · 35s on a 2" YJ · 33s on a 3" YJ
Fitment disclaimer: Clearance depends on exact tire size, wheel specs, suspension and how hard you flex. Confirm with your tire shop or installer before buying.
Tire size how-tos: How to read a tire size · Bolt pattern & backspacing · Regearing for bigger tires · Tire pressure after upsizing · Speedometer error · Rubbing fixes