6L80 cooler lines use quick-connect fittings at the trans and radiator. Removing them without the right tool destroys the fitting. Here's the right way.
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What makes 6L80 cooler lines different
- Quick-disconnect fittings (not flare or push-on)
- Internal locking clip
- Requires special release tool
- Read our transmission cooler line types
Tools needed
- Trans cooler line disconnect tool (specific to 6L80 size)
- Some kits include multiple sizes
- Cost: $15-$40 tool kit
- Auto parts stores often rent or loan
Disconnect procedure
- Vehicle on jack stands
- Catch pan under fitting
- Slide disconnect tool over line
- Push tool into fitting until you feel resistance release
- Pull line out of fitting
- Fluid will drain — catch it
Common mistakes
- Using pliers (destroys fitting)
- Wrong size disconnect tool
- Pulling on line without releasing clip
- Forgetting to catch fluid
- Read our transmission rebuild mistakes
When line is damaged
- Replacement line: $30-$80
- Some applications need full assembly
- Verify fitting size before purchase
Reconnect
- Push line back into fitting until you hear/feel click
- Pull lightly to verify locked
- Top off fluid
- Read our transmission cooler line leak
Pair with aux cooler upgrade
- If accessing cooler lines anyway
- Add aux cooler now
- Read our transmission cooler installation
Need 6L80 cooler lines or tools? Shop our 6L80 catalog. Cooler lines, fittings, aux coolers. Free shipping over $70.
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