6L, 8L & 10L Automatic Transmission Cooler Adapter with Thermostat

Improved Racing is proud to announce the first direct bolt-on, thermostatic transmission fluid cooler adapter for GM's 6L, 8L, and 10L automatic transmissions.

The adapter's built-in thermostat automatically bypasses the transmission cooler until the fluid reaches operating temperature. This eliminates rough shifts caused by overcooling the transmission, reduces wear, and improves horsepower and longevity. You can now get your transmission up to temp quickly and still have all of the cooling capacity you need for high load activities such as towing or racing. It's the best of both worlds!

The adapter features standard female -6AN O-ring boss ports that accept optional male adapter fittings for 5/16", 3/8", 1/2" hose barbs or male AN fittings. This allows you to run common rubber transmission cooler lines or braided AN lines.

Important Application Notes:

• This adapter must be used in conjunction with an external transmission fluid cooler.
• This adapter does not connect directly to the factory transmission cooler lines. Aftermarket lines or adapter fittings must be used.
• This adapter will only help resolve rough shifting issues if they are caused by overcooling of the transmission, usually due to the addition of a larger aftermarket transmission cooler. Note that 8L45 and 8L90 transmissions rough shifting issues can often be resolved through GM TSB 18-NA-355 and by simply flushing the transmission fluid.

Features and Benefits

• 100% bolt-on for 6L, 8L, and 10L series General Motors automatic transmissions
• Built-in thermostat reduces wear, improves horsepower, and eliminates rough shifting by preventing fluid temperatures from dropping below optimal levels
• Rebuildable: Rebuild kits available, or send it back to us for a rebuild under warranty
• -6AN female O-ring boss ports for connection flexibility; choose any line size and type you want
• 6061-T6 billet aluminum construction with black MIL-A-8625 Type II anodized finish
• Uses the factory GM transmission cooler adapter gasket
• Lifetime Warranty
• Made in the USA

Optional hose barb and male AN adapter fittings available

Temperature Rating Specifications

Includes

• 1x TGM-100 transmission cooler adapter block with built-in thermostat
• 1x Transmission cooler adapter gasket, GM Part # 23135703
• 1x Zinc-plated steel mounting screws
• Installation instructions

Applications

• Fits most General Motors 6L, 8L, and 10L series automatic transmissions, including:
  • All 45, 50, 60, 70, 80, 90 variants, and aftermarket performance versions
  • Fits both E and non-E transmission variants
• Applications include:
  • 6L45
  • 6L50
  • 6L80 / 6L80-E
  • 6L90 / 6L90-E
  • 8L45 / 8L45-E
  • 8L90 / 8L90-E
  • 10L80 / 10L80-E
  • 10L90 / 10L90-E
• Note: Has not been verified to fit Allison 10L1000 transmissions (RPO code MGM & MGU)