The Aftermarket GM 8L90 Transmission: Improvements That Matter

The Aftermarket GM 8L90 Transmission: Improvements That Matter

When GM launched the 8L90 (RPO: M5U) in 2014 as an 8-speed automatic transmission designed for high-performance and heavy-duty use, it brought serious torque handling and fuel efficiency to trucks, SUVs, and performance cars. Found in vehicles like the Corvette, Camaro SS, Silverado, and Escalade, the 8L90 quickly became the go-to gearbox for drivers who wanted fast shifts and rugged reliability.

But like any transmission, the 8L90 had its share of growing pains, and over the years, both GM and top-tier remanufacturers have made major improvements that have taken this transmission from "solid" to "exceptional."

Here’s a deep dive into the improvements that matter most:

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Internal Component Upgrades

1. Improved Torque Converter Design
One of the earliest complaints on the 8L90 was shuddering under light throttle, often traced back to the torque converter’s lockup clutch. Modern updates include:

• Redesigned damper and clutch packs to reduce vibration

• Higher-quality friction materials

• Better fluid flow for smoother engagement

These changes drastically reduce the dreaded “torque converter shudder” and improve drivability.

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2. Upgraded Valve Body & TCM Calibration
Hard or erratic shifting? That’s often due to the valve body or transmission control module (TCM) software.

• Valve bodies are now vacuum-tested and rebuilt with improved solenoids

• Updated GM calibrations and reman TCMs reprogrammed to latest specs

• Shift timing and line pressure have been fine-tuned for better feel and longevity

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3. Better Clutch Packs and Clearances
Original 8L90s sometimes suffered from premature clutch wear, especially under aggressive driving or heavy loads.

• Remanufactured units now feature updated clutch materials

• Optimized clutch clearances help improve shift quality and durability

• Thermal management improvements help reduce heat soak, a known issue in earlier years. All of our units include the Cooler Bypass Delete kit as well... Free of Charge!

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Software & Control Improvements

4. Updated TCM Strategies
GM has released multiple TSBs and calibration updates since launch. These include:

• Revised shift schedules

• Torque management tweaks for better throttle response

• Gear learning algorithms that adapt to driving style

Remanufactured units often come pre-loaded with these updates, eliminating the need for a dealer flash.

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Cooling & Lubrication Enhancements

5. Enhanced Fluid Pathways
A huge factor in the reliability of any transmission is heat management. Later revisions of the 8L90 include:

• Improved oil circuit design to reduce internal hotspots

• Tighter control over clutch-to-clutch transition lubrication

• Optional external transmission cooler kits to improve long-term durability (especially in towing/hauling applications)(See: Included Thermal Bypass Kit)

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What Makes Remanufactured 8L90s Better?

At Go Powertrain, our remanufactured 8L90 transmissions go through a multi-stage process that addresses all of GM’s weak points and takes it a step further:

• New seals, gaskets, and high-energy frictions

• Precision machining and dyno testing under load

• Zero-mile torque converter with reinforced internals

• Updated valve body & solenoids with dyno-verified calibration

These aren't just repaired — they're rebuilt stronger than factory specs.

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Looking for a Reman 8L90 That’s Built to Last?
Check out our current inventory at www.gptwholesale.com or call us today. Every unit is backed by our warranty and built by certified techs who know these transmissions inside and out.

 

We are currently proud to offer these for the following fitments:

2014 Chevrolet Silverado 1500
2014 GMC Sierra 1500
2015 Chevrolet Silverado 2500HD
2015 GMC Sierra 2500HD
2015 Chevrolet Suburban
2015 Chevrolet Tahoe
2015 GMC Yukon
2015 GMC Yukon XL
2015 Cadillac Escalade
2015 Cadillac Escalade ESV
2015 Chevrolet Corvette (C7) Stingray
2015 Chevrolet Corvette (C7) Z06
2015–present Chevrolet Silverado 1500 (GMT K2XX)
2015–present GMC Sierra 1500 (GMT K2XX)
2015–2017 Cadillac Escalade (GMT K2XX)
2015–2017 Cadillac Escalade ESV
2015–2017 GMC Yukon Denali
2015–2017 GMC Yukon Denali XL
2015–2019 Chevrolet Corvette (C7 – Stingray & Z06)
2015–2019 Chevrolet Silverado/GMC Sierra HD
2016–present Cadillac ATS V
2016–2019 Chevrolet Camaro (with 8L90)
2016–2019 Cadillac ATS & ATS V
2016–2019 Cadillac CTS & CTS V
2016–2019 Cadillac CT6
2017–2019 GMC Canyon
2017–2019 Chevrolet Colorado (some trims with 8 speed)