10L1000 Fill Plug | 2017 - 2026

This is the transmission fill plug for the Allison 10L1000 10-speed automatic used behind the L5P 6.6L Duramax in Silverado and Sierra 2500HD/3500HD trucks. It seals the fill port after the transmission is filled or topped off. A lost, damaged or stripped plug leaves the fill port open, so replace it whenever the original is missing, the threads or head are damaged, or it no longer seals. GM part number 11602946.

Key Features

• Fill plug for the Allison 10L1000 10-speed transmission
• GM part number 11602946
• Direct replacement for the original plug

Benefits

• Closes the fill port so fluid stays in and dirt stays out
• Good to have on hand during a fluid change or filter service
• Replaces a plug with damaged threads or a rounded head

Frequently Asked Questions

Does this fit the 6-speed Allison 1000?
No. This plug is for the 10-speed Allison 10L1000 used in 2020 and newer trucks.

When should I replace the fill plug?
Replace it if it is missing, the threads or head are damaged, or it leaks after it is tightened.

What else should I have for a 10L1000 fluid service?
Most owners also replace the transmission filter. The 10L1000 filter with seal is linked below.

Fitment

• 2020-2025 Chevy Silverado and GMC Sierra 2500HD/3500HD with 6.6L Duramax L5P and Allison 10L1000 10-speed transmission

Servicing a 10L1000? See the Transmission Filter with Seal 10L1000, the 10L1000 Deep Transmission Pan for L5P and the GM/Allison 10L1000 Tech Manual.

What's Included

• (1) 10L1000 transmission fill plug

For warranty information or to submit a claim, see our Warranty Form.