Transpak For 65-87 TH400 Transmission
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B & M Transpak For 65-87 TH400 Transmission

Part No. 20228 Warranty Details  

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The B&M Transpak has all the features in the Shift Improver Kit, plus it provides additional driver manual control. Retain full automatic features and standard shift points with selector in Drive.

Product Features:
  • Recalibrate Auto Transmission
  • Optimum Performance
  • Select Your App. Mode
  • Improves Transmission Life
  • Transmission Removal Not Required
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1 Question | 1 Answer
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  • Q:

    What do these kits do and how are they installed?
    Asked on 1/24/2013 by tomdickharry from topeka,ks

    1 answer



      This part B & M Transpak - Buick, Chevrolet, GMC, Olds, Pontiac - '65-'87 TH-400, 375 and M40, Part No. 20228 provides additional driver manual control (GM TH-400, 350, Ford C-6 & Chrysler Torqueflite only). Most stock automatic transmissions won't downshift into low gear above 15 mph, and automatically upshift at a predetermined speed no matter what gear you're in. With the Transpak, you can downshift at any speed, and you can hold the transmission in first gear to any speed that you want! This is an asset when you've got a modified engine, and you want additional RPMs, or you're towing a trailer or driving heavy loads downhill., Stage 1 Heavy Duty - For street rods, normal passenger vehicles or other heavy duty use. Firmer shift feel but not harsh. Improves transmission performance and life dramatically without loss of comfort. Normal automatic operation when in "Drive"., Stage 2 Hi-Performance Street - For full performance street use. Essentially the same as Heavy Duty mode except shift is much quicker. Retain full automatic features and standard shift points with selector in "Drive". Please check the installation instructions for this part that has been sent to your email address.
      For any further assistance, please feel free to call us at 1-877-238-2623 or visit your nearest Advance Auto Parts store and our representatives would be more than happy to assist you.

      Answered on 1/25/2013 by Aaron from AAP
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