1965-1987 GM TH400, TH375 & TH475 Automatic Transmissions.

PART# 20260

The B&M® Shift Improver kits™ feature two options to recalibrating your 1965-1987 GM TH400, TH375 and TH475 automatic transmissions. First is the HEAVY DUTY set-up, giving you firm positive shifts without loss of driver comfort for improved performance in all street vehicles. This is a great option for performance street driving or towing. The second is our STREET/STRIP set-up. Be warned, this will deliver firm positive shifts you will feel, along with easily chirping the tires when shifting somewhat aggressively. This setting is recommend for high performance street/strip use, or for competitive events when you want the hardest, quickest shifts possible from a shift improver kit.


Perfect for Towing or Street/Strip Use

Eliminates Soft and Sluggish Shift

Recalibrates Stock Transmissions

Over 65 Years of B&M Quality

Eliminates Shift Overlap

Provides Crisp Shifts

Automotive Item Grade High Performance

Brand B&M

California Proposition 65 Chemical Name Cadmium and cadmium compounds

California Proposition 65 Required Yes

Emission Code 5

Gasket Included Yes

Instructions Included Yes

Manual Control No

Product Type Automatic Transmission Valve Body Kit

Part Number 20260

More Information
Part Type Shifters
Product Line Auto Trans Shift Kits, Transmission & Drivetrain
Brand B&M
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