Product images and videos are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Drivetrain› Automatic Transmissions and Components
B&M
SHIFT IMPROVER KIT 65-87 TH400
SKU: B00M 20260
Moderate — 2–4 hours
Overview
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Part #: 20260
The B&M (R) Shift Improver kits (TM) 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.
Features:
- 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
1965-1987 GM TH400, TH375 & TH475 Automatic Transmissions.
Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Fitment
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Specifications
| Brand | B&M |
| Part Number | B00M 20260 |
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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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