Skip to main content
ASK OUR EXPERTS
1-866-464-6553

B&M TRANSMISSION SPEEDOMETER PORT PLUG

Fits GM and B.O.P. TH400 Transmissions

Part # 20301

B&M TRANSMISSION SPEEDOMETER PORT PLUG

In Stock
Free Shipping on orders over $150*
$34.80
Add to Wishlist
5

Emissions

This part is legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.

See Emissions Details
B&M Racing & Performance brings you this billet aluminum speedometer port block-off plug that fits GM and B.O.P. TH400 transmissions. This plug is used to block the mechanical speedometer gear port when upgrading to an electronic speedometer and includes a replaceable Buna-N-rubber o-ring. It features a black Mil-Spec anodized finish for long-lasting good looks, even in harsh conditions. Comes with hardware and instructions for a quick and easy installation.

Features:

  • Billet Aluminum Construction with Engraved B&M Logo
  • Protects Your Transmission from Contaminants during use or storage
  • Replaceable O-ring seal for leak prevention and simple maintenance
  • Perfect for Electronic Speedometer Conversions
  • Mil-Spec Black Anodized Finish for long lasting good looks
  • Includes Stainless Steel Hardware for Superior Corrosion Resistance

About B&M

Shop B&M's official site for automatic shifters, transmissions and components that exceed all your performance enthusiast needs at Holley.com!

Brand B&M
Emission Code5
Item GradeHigh Performance
MaterialAluminum
Product TypeSpeedometer Port Plug
TransmissionB.O.P TH400
GM TH400
UPC090127107454
Part Number20301
5

This part is legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.

*Free Shipping & Handling only offered to the contiguous US on orders over $149, excludes clearance parts and oversized packages.

Some parts are not legal for use in California or other states with similar regulations.