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***With the exception of the TurboClutch model***
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Spragless 400
TH400 Extreme Spragless

***Please read descriptions in their entirety. Images are for illustrative purposes and may NOT ACCURATELY depict each product. It is your responsibility to be well informed before ordering. Please read our Terms of Use for specifics.***

. . .

The TH400 EXtreme Spragless™ is the strongest 3 speed on the planet!

The most common failure in a Turbo 400 is the 2nd gear sprag. This is a mechanical part has to stop the direct drum turning in the opposite direction of transmission rotation the instant the 2nd gear is engaged. Imagine a 9lb drum turning at engine RPM and has to be stopped instantly. What typically happens is the sprag will wear and break or flip over causing a loss of 2nd gear. This will happen from a stock 400 to Hi HP units.

The industry for years has worked to improve the problem GM built into the Turbo 400. The industry solution was to use a larger sprag out of a front wheel drive GM transmission referred to as (Super Sprag). This sprag is larger and has more surface area and it does extend the HP limitation of the 2ng gear sprag. The problem is the Super Sprag is still a mechanical part, it still wears and fails only at a higher HP level. No one seems to know what HP level this new sprag is reliable. When you shock a mechanical part it will fail period. That's what happens every time you pull the shifter on your 400 into 2nd gear.

Steve Griner came up with the solution. If the sprag is a mechanical part. It wears and fails due to shock load. How do we permanently fix it. We remove the sprag from the transmission. No sprag = No sprag Failure. The Turbo 400 EXtreme is a Spragless 400 transmission. That's right!!! There is no sprag to break. The clutches will handle all the shock you can throw at them. You shock the clutch pack it will slip grab and go down the track. You shock a mechanical part it will explode. The Heart of the EXtreme Spragless™400 is the valve body built for EXtreme Automatics™ by Griner® Engineering. Steve Griner started from a block of aluminum billet and a clean sheet of paper. The other guys are still modifying the 40 year old GM cast iron valve body. With the new Valve body the sky was the limit. We removed the 2nd gear sprag, Improved direct clutch life and designed the fastest shift time in the industry. All this was topped off with a Pro Tree .000 release time Griner trans brake the fastest in the industry.

The spragless technology has been tested for years in 10,000lb Fuel Blown monster trucks where no sprag has ever survived. These trucks must be shifted up and down in and out of 2nd gear at full throttle. That's some serious punishment. Imagine a 10,000lb truck. On the Dragstrip the spragless has been 6.21 at over 230 in the quarter when the other big name 3 speed 400s failed. If you are looking for the strongest 3 speed 400 on the planet with the latest innovation The EXtreme Spragless™ 400 is for you.



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All EXtreme Spragless™400s include:

  • Only select cores are used
  • Griner® Billet Alum Extreme Spragless VB W/Pro Tree Brake
  • Case is media blasted and prepped for Racing
  • All New Bushings
  • All New Torrington® Bearings
  • Rear Case Torrington® Thrust
  • Case Modified for Maximum Fluid Flow
  • New HD Output Shaft
  • Gear Set Rollerized Thrust
  • 2.48 Gear Set New Pinions and Thrust Washers
  • Spragless Technology
  • Pressure Regulated System to Prevent Engine Thrust Wear

. . .

EXtreme Spragless Stage I • Up to 1300HP

  • Build
  • Items Included in Extreme 400
  • Griner® Pro Tree .000 Release Trans Brake
  • Hytuff® Input Shaft with Special Design Oversize spline
  • HYtuff Intermediate Shaft
  • Roller 2.48 Gear Set
  • Hardened Stator Support
  • Intermediate Snap Ring case Support
  • Billet Clutch Hub
  • Deep Pan
  • Hi Flow Filter
  • 1 Year Warranty

Stage I Spragless 400 • Options

  • Safe Neutral $100
  • 2nd Gear Leaver option $100
  • 2.10 Billet 6 Pinion Straight Cut Gear Set $1650
  • 1.86/1.33/1.0 Straight Gear Set $2395
  • Sheet Aluminum Pan $160
  • Billet 4340 Output Shaft $595
  • Boost Builder Stall Control $1095
  • JW® Ultra Bell GM $295
  • JW® Ultra Bell Most Other $695 Package
  • VSS Package for GM and Ford $275
  • Big Shaft Package $1650
  • Reid SFI Case Package Case, Bell, Tail shaft $2200
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$2895 + Shipping • Buy Now



EXtreme Spragless Stage II • Up to 1600HP

  • Build
  • Items Included in All Extreme 400s
  • Griner® Pro Tree .000 release Trans Brake
  • 300M Input Shaft
  • Special Design Hytuff Mainshaft
  • 7075 Aluminum Direct Drum
  • Maximum Duty Clutch Packs
  • Rollerized Direct Drum
  • Billet Clutch Hub
  • Intermediate Snap Ring Case Support
  • Deep Cast Aluminum or Derale® Cooling Tube Pan
  • 2.48 HD Gear Set
  • Hi Flow Filter
  • 1 Year Warranty

Stage II Spragless 400 • Options

  • Safe Neutral $100
  • 2nd Gear Leaver option $100
  • 2.10 Billet 6 Pinion Straight Cut Gear Set $1650
  • 1.86/1.33/1.0 Straight Gear Set $2395
  • Sheet Aluminum Pan $160
  • Billet 4340 Output Shaft $595
  • Boost Builder Stall Control $1095
  • JW® Ultra Bell GM $295
  • JW® Ultra Bell Most Other $695 Package
  • VSS Package for GM and Ford $275
  • Big Shaft Package $1650
  • Reid SFI Case Package Case, Bell, Tail shaft $2200
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$3695 + Shipping • Buy Now

EXtreme Spragless Stage III • Up to 2000HP +

  • Build
  • Items Listed is All Extreme 400s
  • VascoMax® Input Shaft
  • Aircraft Quality CNC 7075 Aluminum Forward Drum with 4340 Steel hub
  • CNC Over Size Input Spline
  • VascoMax® Main Shaft
  • Billet Forward Clutch Hub
  • Aircraft Quality CNC 7075 Aluminum Direct Drum
  • Billet Hardened Stator Support
  • Special Design Pressure Regulator System Adjustable 150-250 psi
  • HD 2.48 Gear Set
  • Maximum Duty Clutch Packs
  • Super Pump Assembly
  • Rollerized Direct Drum
  • Deep Cast Aluminum or Derale® Cooling Tube Pan
  • Hi Flow Filter
  • 12 -14 lb lighter rotating mass
  • 1 Year Warranty

Stage III Spragless 400 • Options

  • Safe Neutral $100
  • 2nd Gear Leaver option $100
  • 2.10 Billet 6 Pinion Straight Cut Gear Set $1650
  • 1.86/1.33/1.0 Straight Gear Set $2395
  • Sheet Aluminum Pan $160
  • Billet 4340 Output Shaft $595
  • Boost Builder Stall Control $1095
  • JW® Ultra Bell GM $295
  • JW® Ultra Bell Most Other $695 Package
  • VSS Package for GM and Ford $275
  • Big Shaft Package $1650
  • Reid SFI Case Package Case, Bell, Tail shaft $2200
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$4295 + Shipping • Buy Now

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