USE COUPON CODE "SUMMER26"

Your cart

Your cart is empty

Shop 4.0L

Upgrade Your 4.0L Engine with FastHemis The 4.0L inline-six engine is known for its durability and smooth power delivery, commonly found in Jeep models like the Wrangler and Cherokee. Its robust design offers a solid foundation for both daily driving reliability and moderate performance enhancements. At FastHemis, you'll find a range of parts tailored to the 4.0L platform, including intake and exhaust upgrades, ignition components, and tuning accessories. These parts help improve throttle response, efficiency, and overall engine capability without compromising the engine’s legendary reliability. Key upgrades for your 4.0L engine include: - High-flow air intake systems - Performance exhaust components - Ignition and spark upgrades - Engine management and tuning tools Shop 4.0L engine upgrades at FastHemis.
SELECT YOUR VEHICLE

1006 Results

Magnaflow Universal Catalytic Converter: Jeep Wrangler (97-06)
Magnaflow Universal Catalytic Converter: Jeep Wrangler (97-06)
usa
Liqui Moly Special Tec B FE Motor Oil: Fits Most Dodge / Jeep Models
Liqui Moly Special Tec B FE Motor Oil: Fits Most Dodge / Jeep Models
Westin Black Signature 3 Nerf Step Bars: Jeep Wrangler 1997-2006
Westin Black Signature 3 Nerf Step Bars: Jeep Wrangler 1997-2006
Method Wheels 322 / Gloss Black | 17x8.5 | 5x5 | 0/4.72"
Method Wheels 322 / Gloss Black | 17x8.5 | 5x5 | 0/4.72"

Method Wheels 322 / Gloss Black | 17x8.5 | 5x5 | 0/4.72"

Method Wheels

$335.00

Unit price
per 

Westin Black E-Series Nerf Step Bars: Jeep Wrangler 1997-2006
Westin Black E-Series Nerf Step Bars: Jeep Wrangler 1997-2006
Method Wheels 708 / Gloss Titanium | 17x8.5 | 5x5 | 0/4.72"
Method Wheels 708 / Gloss Titanium | 17x8.5 | 5x5 | 0/4.72"

Method Wheels 708 / Gloss Titanium | 17x8.5 | 5x5 | 0/4.72"

Method Wheels

$366.00

Unit price
per 

Method Wheels 708 / Gloss Titanium | 17x9 | 5x5 | -38/3.5"
Method Wheels 708 / Gloss Titanium | 17x9 | 5x5 | -38/3.5"

Method Wheels 708 / Gloss Titanium | 17x9 | 5x5 | -38/3.5"

Method Wheels

$387.00

Unit price
per 

Method Wheels 701 /  Bahia Blue® | 17x9 | 5x5 | -12/4.62"
Method Wheels 701 /  Bahia Blue® | 17x9 | 5x5 | -12/4.62"

Method Wheels 701 / Bahia Blue® | 17x9 | 5x5 | -12/4.62"

Method Wheels

$387.00

Unit price
per 

Rancho RS5000X Front Shock: Jeep Wrangler 1997-2006
Rancho RS5000X Front Shock: Jeep Wrangler 1997-2006

Rancho RS5000X Front Shock: Jeep Wrangler 1997-2006

Rancho

$90.67

Unit price
per 

Energy Suspension Black 1in Body Lift Kit: Jeep Wrangler 1994-2006
Energy Suspension Black 1in Body Lift Kit: Jeep Wrangler 1994-2006
usa

Energy Suspension Black 1in Body Lift Kit: Jeep Wrangler 1994-2006

Energy Suspension

Regular price $425.58 $283.72 33% off

Unit price
per 

DiabloSport 9050 - Trinity T2 MX Vehicle Monitor
DiabloSport 9050 - Trinity T2 MX Vehicle Monitor

DiabloSport 9050 - Trinity T2 MX Vehicle Monitor

Diablo Sport

Regular price $771.95 $685.95 11% off

Unit price
per 

Zone Offroad Front Sway Bar Links: Jeep Grand Cherokee WJ (1999-2004)
usa
Flowmaster Force II Cat-Back Exhaust System: Jeep Wrangler (00-06)
Flowmaster Force II Cat-Back Exhaust System: Jeep Wrangler (00-06)
usa

Flowmaster Force II Cat-Back Exhaust System: Jeep Wrangler (00-06)

Flowmaster

Regular price $827.95 $661.95 20% off

Unit price
per 

Method Wheels 105 / Beadlock / Matte Black | 17x9 | 5x5 | -38mm/3.5"
Method Wheels 105 / Beadlock / Matte Black | 17x9 | 5x5 | -38mm/3.5"
Bestop Window Storage Bag: Fits Jeep Wrangler 1997-2025
ARB Wheel Carrier Rear Bar (REAR): Jeep Wrangler 1997-2012
ARB Wheel Carrier Rear Bar (REAR): Jeep Wrangler 1997-2012
ARB Hilift Bracket: Jeep Wrangler 1997-2006
ARB Hilift Bracket: Jeep Wrangler 1997-2006

ARB Hilift Bracket: Jeep Wrangler 1997-2006

ARB

$151.00

Unit price
per 

Prothane Black Body Mount Kit: Jeep Wrangler 1997-2006
usa

Prothane Black Body Mount Kit: Jeep Wrangler 1997-2006

Prothane

$210.05

Unit price
per 

Bilstein B8 5100 Front Shock Absorber 3.5-4" Lift Long Arm: Jeep Wrangler TJ 1997-2006
Bilstein B8 5100 Front Shock Absorber 3.5-4" Lift Long Arm: Jeep Wrangler TJ 1997-2006

Bilstein B8 5100 Front Shock Absorber 3.5-4" Lift Long Arm: Jeep Wrangler TJ 1997-2006

Bilstein

Regular price $171.85 $123.00 28% off

Unit price
per 

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.

SELECT YOUR VEHICLE