Shop 4.0L
American Brother Designs Hitch Cover 2" Receiver: Durango, Jeep & Ram Models
American Brother Designs
Regular price
$108.00
$58.00
46% off
- Unit price
- /per
ANZO Crystal Headlights w/ Light Bar (Black): Jeep Grand Cherokee 1999 - 2004
ANZO
$511.00
- Unit price
- /per
Anzo LED Tail Lights w/Light Bars (Chrome/Red): Jeep Grand Cherokee 1999 - 2004
ANZO
$365.00
- Unit price
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Anzo LED Tail Lights w/Light Bars (Black/Smoke): Jeep Grand Cherokee 1999 - 2004
ANZO
$365.00
- Unit price
- /per
Anzo LED Tail Lights w/Light Bars (Black): Jeep Grand Cherokee 1999 - 2004
ANZO
$365.00
- Unit price
- /per
S&B Cold Air Intake: Jeep Wrangler TJ 4.0L 1997 - 2006
S&B Filters
Regular price
$429.99
$379.00
12% off
- Unit price
- /per
2 filter types
Bilstein B8 5100 Shock Absorber Rear 3.5-6" Lift Long Arm: Jeep Wrangler TJ 1997-2006
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
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Bilstein B8 5100 Shock Absorber Rear 3.5-4" Lift Short Arm: Jeep Wrangler TJ 1997-2006
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
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Bilstein B8 5100 Rear Shock: Jeep Grand Cherokee 1993 - 1998 (w/ 1.5-2" Rear Lift)
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
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Bilstein B8 5100 Rear Shock: Jeep Grand Cherokee 1999 - 2004 (w/ 3-4" Rear Lift)
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
- /per
Bilstein B8 5100 Shock Absorber Rear 6" Lift: Jeep Grand Cherokee ZJ 1993-1998
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
- /per
Bilstein B8 5100 Shock Absorber Front 3.5-4" Lift Short Arm: Jeep Wrangler TJ 1997-2006
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
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Bilstein B8 5100 Front Shock: Jeep Wrangler TJ 1997 - 2006 (w/ 4.5" Front Lift & Long Arm Lift Kit)
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
- /per
Bilstein B8 5100 Shock Absorber Rear 3-4" Lift: Jeep Grand Cherokee ZJ 1993-1998
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
- /per
Bilstein B8 5100 Front Shock Absorber 3" Lift: Jeep Grand Cherokee ZJ 1993-1998
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
- /per
Bilstein B8 5100 Rear Shock Absorber 3" Lift Short Arm: Jeep Wrangler TJ 1997-2006
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
- /per
Bilstein B8 5100 Front Shock Absorber 3" Lift Short Arm: Jeep Wrangler TJ 1997-2006
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
- /per
Bilstein B6 4600 Rear Shock: Jeep Grand Cherokee 1999 - 2004 (w/ OEM Ride Height)
Bilstein
Regular price
$136.85
$92.00
33% off
- Unit price
- /per
Bilstein B6 4600 Front Shock: Jeep Grand Cherokee 1999 - 2004 (w/ OEM Ride Height)
Bilstein
Regular price
$154.85
$104.00
33% off
- Unit price
- /per
Bilstein B6 4600 Rear Shock Absorber (REAR): Jeep Grand Cherokee ZJ 1993-1998
Bilstein
Regular price
$136.85
$92.00
33% off
- Unit price
- /per
Bilstein B8 5100 Shock Absorber Rear 0-2" Lift (REAR): Jeep Wrangler TJ 1997-2006
Bilstein
Regular price
$171.85
$123.00
28% off
- Unit price
- /per
Eibach 30mm Wheel Spacers (Pair): Jeep Grand Cherokee (93-98) & Wrangler (97-06)
Eibach
Regular price
$261.11
$235.00
10% off
- Unit price
- /per
Borla Touring Cat-Back Exhaust System (Polished Tip): Jeep Wrangler 1997 - 1999 (2.5L & 4.0L)
Borla
Regular price
$799.99
$713.99
11% off
- Unit price
- /per
Borla SS Single Right Rear Exit Cat-Back Exhaust: Jeep Wrangler YJ 4.0L 6cyl 4WD 2Dr 1991 - 1995
Borla
Regular price
$716.99
$639.99
11% off
- Unit price
- /per
MBRP Cat Back Exhaust (Single Turndown): Jeep Wrangler TJ Unlimited 4.0L (97-06) - Aluminized
MBRP
Regular price
$333.52
$269.99
19% off
- Unit price
- /per
MBRP Cat Back Exhaust (Single Turndown) (REAR): Jeep Wrangler TJ Unlimited 4.0L (97-06)
MBRP
Regular price
$401.46
$324.99
19% off
- Unit price
- /per
MBRP Cat Back Exhaust System (Single Side Exit, Black): Jeep Wrangler TJ 1997 - 1999 (2.5L & 4.0L)
MBRP
Regular price
$426.16
$344.99
19% off
- Unit price
- /per
MBRP Cat Back Exhaust (Single Side Exit): Jeep Wrangler TJ (97-06) 2.5L & 4.0L w/ Hardware
MBRP
Regular price
$352.05
$284.99
19% off
- Unit price
- /per
MBRP Cat Back Exhaust System (Single Side Exit): Jeep Wrangler TJ 1997 - 1999 (2.5L & 4.0L)
MBRP
Regular price
$401.46
$324.99
19% off
- Unit price
- /per
Spec D LED Projector HeadLights (Chrome): Jeep Grand Cherokee 1999 - 2004
Spec D
Regular price
$207.00
$153.00
26% off
- Unit price
- /per
Spec D CCFL Projector Headlights (Black):Jeep Grand Cherokee 1999 - 2004
Spec D
Regular price
$360.00
$267.00
26% off
- Unit price
- /per
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Performance Upgrades for Your 4.0L Inline-Six Engine
The 4.0L inline-six engine is a durable and smooth-running powerplant widely recognized in Jeep Wrangler and Cherokee models. Known for its reliability and balanced power delivery, this engine offers a solid base for bolt-on performance enhancements that improve throttle response and efficiency without sacrificing longevity.
Key Performance Upgrades for the 4.0L Engine
Enhancing your 4.0L engine focuses on improving airflow, ignition, and engine management to unlock better throttle response and overall drivability. Popular upgrades include high-flow intake systems that increase air volume, performance exhaust components that reduce backpressure, and ignition upgrades that ensure stronger, more consistent sparks.
- High-flow air intake systems to boost airflow and efficiency
- Performance exhaust components for improved scavenging and sound
- Ignition and spark upgrades to optimize combustion
- Engine management and tuning tools for precise calibration
How to Maintain Reliability While Upgrading Your 4.0L
The 4.0L engine’s reputation for durability means upgrades should complement its robust design without over-stressing components. Focus on bolt-on parts that enhance performance within the engine’s mechanical limits. Proper tuning and quality parts help maintain reliability while extracting more capability from your engine.
Find the Right 4.0L Engine Parts at FastHemis
At FastHemis, we offer a curated selection of 4.0L engine upgrades designed to improve performance and maintain reliability. Whether you’re looking for intake kits, exhaust solutions, ignition components, or tuning accessories, our parts are fitment-focused and engineered for your Jeep’s inline-six. Shop the 4.0L collection today to enhance your engine’s capability.