Drivetrain› Automatic Transmissions and Components
B&M
SHIFT IMPROVER KIT 88-94 TH400
SKU: B00M 20261
Moderate — 2–4 hours
Description
Part #: 20261
The B&M (R) Shift Improver kits (TM) feature two options to recalibrating your 1988-1994 GM TH400 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 Off-Road, Towing or Street/Strip Use
- Eliminates Soft and Sluggish Shifts
- Over 65 Years of B&M Quality
- Eliminates Shift Overlap
- Provides Crisp Shifts
- Easy Installation
Automatic Transmission Shift Kit - Shift Improver - TH400 1988-90 - Kit
MIA's Description
Fitment
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Specifications
| Brand | B&M |
| Part Number | B00M 20261 |
Buy with Confidence
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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