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The 4.4 ratio apply lever applies 2nd gear. 2nd gear in the 47RE is a band that wraps around the front drum. This drum is spinning in first gear and when the band applies and stops this drum, you are now in 2nd gear.

There is a piston(servo) that fills with hydraulic fluid to apply the band. The 4.4 ratio apply lever is in between the piston and the band itself. It acts like a prybar. It causes a mechanical advantage. Placing one pound of force on the tip of the apply lever causes 4.4 pounds of force on the band.

The factory apply lever from '94-'02 had a 3.8 ratio. Using the the 4.4 ratio gives us 15% more torque capacity in second gear than the stock setup at equal pressures.

You might ask yourself, then why don't we use a 5.0 ratio or 7.0 or more. 2nd gear would be stronger, right?

Yes, but 2-3 bind up is a major problem with these trannies. Changing the ratio of the apply lever has side effects. Now the piston has to travel farther to apply the band. We are limited in how far the piston can travel. It also affects the speed of the release of the band. We have to make sure 2nd gear is released before third gear applies or else 3rd gear will suffer damage. DTT trannies use a special setup of clutch timing and clearances that was designed to work well around the 4.4 ratio lever. It's just one part of complex system that was designed to work together.

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Chris Strickland