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American Powertrain

ProFit Transmission Swap, Tremec TKX 5-speed, 1978-88 G-Body, .68 OD

Vehicle Specific View fitment for 9 models
Part# L241539
Mfg# COGM-G1X
Sold As Set
$3,811.99
List Price: $4,193.95
You Save $381.96

Ships direct from manufacturer
Allow 2-6 weeks for item to arrive.
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Designed to Fit Your Classic 600 lbs/ft of torque capacity

American Powertrain ProFit Tremec TKX manual transmissions and installation kits are designed to fit your classic muscle cars. The TKX has a more streamlined case than the normally used OE design T-56 and T-5 which provides clearance in most transmission tunnels. The rigid 3-piece aluminum housing capable of engines speeds of 8,000 rpm with shifts at 7,500 rpm. TKX 5-Speed Manual Transmission Features and Benefits • Designed, tested and built specifically for the aftermarket. • Designed for multiple applications with three shifter locations. Compact, end-loaded design provides clearance in most transmission tunnels without floor modifications. • Increased case strength with three-piece aluminum housing provides outstanding structural stiffness (includes main case, intermediate plate and rear extension). Gaskets at all flanges simplifies installation and eliminates fluid leaks. • Superior shift-ability through use of multi-cone synchronizers and hybrid synchronizer rings made of sintered bronze and carbon • Noise, vibration and harshness (NVH) minimized with gear layout to best control stress levels. All gears supported by caged needle bearings to reduce end play on the gears. • Equipped with a high-performance short-throw billet aluminum shifter that isolates road noise, while providing clean, crisp shifts. • Robust design with internal three-rail shift system and steel shift forks. • Wide gear width increases gear life and torque capacity. • Built-in reverse light switch and cruise control safety switch.

Tech Spec: Gear ratios: 1st 2.87, 2nd 1.89, 3rd 1.28, 4th 1.00, 5th 0.68. 26-spline input shaft. 31 spline output. All gears and shafts made from special grade steel (ASTM 4615) 600ft-lb Constant Load Rated Kit Includes: Tremec TKX17805 TREMEC Flip Shifter - OE 4-speed shift position Driveshaft Slip Yoke - 1330 Solid Yoke, Cryo Hardened Steel Mechanical Speedometer Conversion - Cable adapter compatible with OE cable VSS Wiring Harness - For electronic speedometer or fuel injection ECU Reverse Light Wiring - Weatherseal harness, non-polar L241507 Crossmember Poly Trans mount Pilot Bearing - Roller steel, grease pre-pack (LS and non-LS engine included) Shift Knob - White w/black 5-speed pattern Hardware, Warranty and Instructions

Notes

  • Shifter stick not included.
  • Optional Hydraulic Pedal Kit recommended L241508-5S.
  • Optional Bellhousing CH33394.
  • Tunnel modification required.
  • This item is not eligible for any further discounts or promotional pricing.
  • SHIP NOTE: This item exceeds standard size and is exempt from free shipping.
  • SHIP NOTE: This item is SPECIAL ORDER and will drop-ship from the manufacturer. While the majority of drop ship orders experience no delays, please be advised that OPGI does not control delivery times.

Find Item In This Catalog

  • 2024 GM G-Body 1978-1988 127
WARNING: This product can expose you to chemicals including lead, sulfur, nickel, chromium, vanadium, titanium, polyvinyl chloride, and 4,4’-methylenebis (2-chloroaniline), which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.

Vehicle Fitment

Year Make Model Application Details
1982 Buick Grand National  
1984–1987 Buick Grand National  
1978–1987 Buick Regal  
1983–1987 Buick T-Type  
1978–1987 Chevrolet El Camino  
1978–1983 Chevrolet Malibu  
1978–1988 Chevrolet Monte Carlo  
1978–1988 Oldsmobile Cutlass  
1978–1986 Pontiac Bonneville  
1978–1987 Pontiac Grand Prix  
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ProFit Transmission Swap, Tremec TKX 5-speed, 1978-88 G-Body, .68 OD
American Powertrain ProFit Transmission Swap, Tremec TKX 5-speed, 1978-88 G-Body, .68 OD