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88-98 Chevy/GMC C1500 Trucks (OBS, GMT400) 5 and 6-speed kit

Pro-Fit C-10 TKO 5-speed and 6-speed Kit for 88-98 Chevy/GMC C1500, OBS, GMT400
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Availability: Kits in stock now please call for a custom quote!


American Powertrain Pro-Fit kits for 88-98 Chevy/GMC C1500 OBS GMT400 truck

Choose either 5 or 6-speed. No cutting the floor!

30-50% increase in fuel economy
Low RPM cruising for greatly reduced driver fatigue and an improved highway driving experience.
Reduced engine wear leading to longer engine life
Cooler engine operating temperatures

TKO Gear Ratios
TKO 500 - 3.27, 1.98, 1.34, 1.00, 0.68
TKO 600 - 2.87, 1.89, 1.28, 1.00, 0.64 OR 0.82

T56 Magnum Gear Ratios
Close Ratio 2.66, 1.78, 1.30, 1.00, 0.80, 0.63
Wide Ratio 2.97, 2.10, 1.46, 1.00, 0.74, 0.50

Kit includes:

AP Revolution Shifter Mechanism locates shifter - will fit bench or bucket seats
Seamless DOM Driveshaft Assembly - Race Balanced, Solid U-Joints
Driveshaft Slip Yoke - Cryogenically hardened steel
Transmission Mount - Polyurethane (TKO kit comes with 2.5" spacer)

Pilot Bearing - Stainless rollers, grease pre-pak
Reverse Light Harness - Weatherseal
Speedometer Conversion Electronic
Shifter Knob
Hardware, Instructions, Warranty

Reuses the stock crossmember. Just requires it to move forward to the next bolt holes and drill. Easy install

Hydraulic clutch recommended. Can use a stock C1500 pedal and factory hydraulic master cylinder. Hydramax bearing adapter line required.


  • 23887217
  • 766897551628
  • Kits in stock now please call for a custom quote!
  • New


Shipping Information

  • Item Requires Shipping
  • 43.0 lbs.
  • W8.0000” x H8.0000” x L32.0000”

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  • Expert Enthusiasts American Powertrain's team is manned by experienced enthusiasts with years of installation experience.
  • 2 Year Warranty Industry leading 24-month warranty from date of installations with 2-year installation grace period.
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