Remanufactured 6T40 Transmission

The 6T40 six-speed automatic transmission is one of GM’s most common front-wheel-drive units, found in a wide range of compact sedans and crossovers. These vehicles are often daily drivers—meaning when the transmission fails, downtime matters and comebacks are costly.

Shops frequently see 6T40 failures tied to heat, fluid degradation, and valve-body wear. Once symptoms like harsh shifts or delayed engagement begin, fluid-only fixes or partial repairs rarely last.

ACE’s remanufactured 6T40 is built to correct the underlying mechanical issues, delivering a reliable, install-ready solution that helps your shop fix the problem once—and move on to the next job.

Built to Correct the 6T40’s Known Weak Points

From the factory, the 6T40 prioritizes efficiency. Over time, that design leaves little margin for heat buildup and pressure loss. ACE remanufactures every 6T40 with upgrades focused on stabilizing hydraulic control and improving long-term durability.

Key build upgrades include:

  • Upgraded torque converter with improved lock-up clutch material
  • Valve body reconditioning to correct internal pressure leaks and erratic shifts
  • Updated clutch packs and steels using high-energy friction materials
  • Pump inspection and re-machining to restore proper hydraulic pressure
  • New solenoids, seals, bushings, and wear components throughout
  • Full dyno testing under load to verify shift timing, engagement, and pressure stability

These upgrades work together to reduce heat, maintain consistent pressure, and eliminate the shift complaints shops see most often on stock units.

Common 6T40 Transmission Problems

If your shop services GM front-wheel-drive vehicles, these 6T40 issues are familiar:

  • Harsh or delayed 2–3 shifts, often caused by valve-body wear
  • Torque converter clutch shudder, especially at light throttle
  • Overheating, accelerating clutch and seal failure
  • Pressure loss, leading to slipping or delayed engagement
  • Repeat failures after fluid-only services

ACE addresses these problems at the component level—preventing the cycle of temporary fixes and repeat visits.

What’s Included with Every ACE 6T40

Each ACE 6T40 transmission ships with:

  • Fully remanufactured and dyno-tested transmission
  • Upgraded torque converter
  • All new clutches, seals, bushings, and wear components
  • Mobil 1 synthetic transmission fluid, included with shipment
  • ACE’s comprehensive warranty —
    Parts, labor, shipping, and Mobil 1 fluid included.
    (see full warranty details)

Everything arrives ready for installation—no missing components, no hidden add-ons.

Compatible Applications

The 6T40 transmission is commonly used in:

  • Chevrolet Cruze
  • Chevrolet Malibu (select years)
  • Chevrolet Equinox (2.4L)
  • GMC Terrain
  • Buick Verano

Exact compatibility varies by year, engine, and drivetrain. VIN confirmation is recommended to ensure proper fitment.

Shipping That Keeps Daily Drivers Moving

Most 6T40-equipped vehicles are relied on every day. ACE supports fast turnaround with:

  • Same-day shipping on in-stock units
  • Secure crating to protect the transmission in transit
  • Nationwide carrier network with tracking provided

We ship directly to your shop or installer to minimize downtime and scheduling delays.

Core Return Policy — No Upfront Deposit

ACE uses a shop-friendly “Due On Receipt” core policy:

  1. No upfront core deposit charged
  2. Core invoiced on paper only
  3. 120 days to return the rebuildable core
  4. Prepaid return labels included
  5. Core invoice cleared once received

This keeps your cash flow intact—especially helpful for high-volume FWD repairs.

Warranty Coverage You Can Stand Behind

EEvery ACE remanufactured transmission is backed by a 3-year nationwide warranty, valid coast to coast across the United States.

Coverage is fully transferable and includes
parts, labor, shipping, and Mobil 1 fluid included.

Full warranty details available here

Installation Notes & Best Practices

To protect performance and warranty coverage:

  • Flush or replace cooler lines before installation
  • Inspect for debris from prior converter failure
  • Perform adaptive relearn procedures when required
  • Verify cooling system operation—heat is a major failure factor
  • Use only Mobil 1 ATF or manufacturer-approved equivalent

Skipping these steps is one of the most common causes of repeat 6T40 issues.

6T40 Transmission FAQs

Q: Is the 6T40 suitable for daily driving after remanufacture?
Yes. ACE builds are designed specifically for reliable commuter and family-vehicle use.

Q: Does ACE include the torque converter?
Yes. Every unit ships with an upgraded torque converter.

Q: Is programming required after installation?
Some vehicles require a relearn or adaptive reset using a GM-capable scan tool.

Q: Does the transmission ship filled with fluid?
Fluid ships with the unit and is added during installation to prevent leaks during transit.

Q: How fast can ACE ship a 6T40?
Most in-stock units ship same-day and arrive within 2–3 business days.

The Bottom Line

The 6T40 is common—and repeat failures don’t have to be.
ACE’s remanufactured 6T40 is built to correct known weak points, stabilize shifting, and reduce comebacks.

Fix it once. Install with confidence.
That’s the ACE standard.