Skip to content
B&M Shift Improver Kit, 1965-1987 GM TH400, TH375 & TH475 (BM20260) BM20260

B&M Shift Improver Kit, 1965-1987 GM TH400, TH375 & TH475 (BM20260)

Suit GM TH400, 375 & M40, Recalibrate Your Transmission
SKU: BM20260
$162.40 - $162.40
$162.40
$162.40 - $162.40
$162.40
+ GST
Stock Status: ⌛ Available — ships from supplier, allow 2–10 days shipping

TH375 400 M40 TRANS SHIFT

Suit GM TH400, 375 & M40, Recalibrate Your Transmission

Part Number: BM20260

The B&M Shift Improver Kit the easiest way to get the stout performance you've always wanted out of your automatic transmission - and you get two modes of performance to select from: Heavy Duty, or Street/Strip. It's our least expensive and simplest to install kit. All you need are some hand tools! In the space of an afternoon, you can turn your transmission into a B&M-tuned unit! Ask the thousands of satisfied customers that have installed one in their transmissions!

  • Recalibrate your automatic transmission for optimum performance & extended life!
  • Select the mode that best suits your application:
    1. STAGE 1. HEAVY DUTY; Firm positive shifts without loss of driver comfort for improved performance in all street vehicles. Recommended for regular passenger vehicles.
    2. STAGE 2. STREET/STRIP; Provides positive shifts for high performance street use or for competitive events. This level is for the enthusiast who wants the hardest, quickest possible shift.
  • Provides crisp shifts on any stock automatic transmission
  • Eliminates shift overlap & excess wear on clutches & bands due to slippage
  • Application: Buick, Chevrolet, GMC, Olds, Pontiac - '65-'87 TH-400, 375 and M40