GM 4L80E Performance Transmission Upgrades

Originally found in 3/4- and 1-ton trucks, the 4L80E and higher-torque 4L85E transmissions share gear ratios with the 3-speed TH400, but add the 4th Gear Overdrive which is popular for high-horsepower street cars. Sonnax upgrades take reliability of these versatile units to the next level for optimum performance in any heavy-duty, street and extreme racing vehicle.

Transmission Upgrades All Transmission Parts Request Catalog

View Performance Parts by Application:

Transmission Parts: Case Internal Pump Servo/Band Valve Body
Torque Converter Parts: Performance Converter Kits
Driveline: Roller Bearing Slip Yoke More Slip Yokes

You helped my 4L80-E survive behind my twin turbo 408 lsx. Great parts and great customer service!
E. Reed

4L80E Performance Pack

Get Max Performance & Durability with One Complete Kit

Performance Input & Main Shafts

Choose Heavy- & Extreme-Duty Options for Any Power Level

Forward Clutch Hubs

Optimize Hub Strength in Heavy- & Extreme-Duty Builds

Case Saver Retainers

Protect Case Lugs from Blow Out & Keep the Intermediate Band

Smart-Tech^® Overrun Clutch Valve Kit

Upgrade OD Clutch Holding Power to Prevent Roller Clutch Failure

Heavy Duty Low/Reverse Servo Pistons & Adjustable Pin Kit

Prevent Breakage & Accurately Set Pin Travel

4L80E Performance & Heavy-Duty Transmission Build Guides

From hardworking trucks to extreme street/strip race vehicles, it’s easy to add unmatched reliability to vehicles of any power level with Sonnax. Check out these handy build guides to get maximum results out of your rebuild.

View Heavy-Duty Truck Basic Build

View High Performance Build - Under 1,000HP

View High Performance Build - Over 1,000HP

The 4L80E HP kit provides a quick easy solution that makes for consistent, reliable builds time and time again, I love this kit!
W. Dunaway, Mr. Wendell's Motorsports

See What's Inside the Sonnax 4L80E Performance Pack

Watch this video to get a full breakdown of everything you get in the most comprehensive transmission upgrade kit on the market for GM 4L80E and 4L85E units: Sonnax Performance Pack HP-4L80E-01. This unique kit includes components to precisely recalibrate pressures and shift accumulation PLUS heavy duty parts to repair damage, prevent future wear and improve reliability. Top builds for maximizing work/sport vehicle performance and durability start here!

Sonnax innovation is second to none!
F. Durgin

Sonnax high performance products meet the toughest challenges faced by hard-working, daily-use drivetrains as well as racing units going all-out on the street or track.

Learn About Sonnax Heavy Duty & High Performance See All Heavy Duty & High Performance Upgrades

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