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Air Throttle Conversion Kits

Automatic or manual transmissions and General Purpose Throttle Control for all others

Complies with FMVSS-124, except the the Panel Mounted Lever Control

*Don't have a Detroit Diesel 6V92, 8V71 or 8V92?
No problem, we have a general purpose throttle control cylinder that may be adapted to your engine.


Original equipment mechanical linkage is very slow, unresponsive, and requires frequent adjustments. The original mechanical linkage can make your leg ache from the constant pedal pressure.

Upgrade your old mechanical throttle linkage to the new quick response and light touch of a pneumatic throttle. An air throttle offers quicker response and more control. Kits maybe installed on manual or automatic transmission coaches. Air throttles are most comfortable on a long trips.

This upgrade also solves the problem of what to do with the original equipment linkage went raising the drivers floor level with the rest of the coach.

Air Line Drawing
All lines except in the engine compartment, are 3/8" O.D. DOT nylon or copper. Air lines in the engine compartment should be braded stainless steel.
Air Throttle Layout
Hello Folks,
There are others selling air throttle parts that may look like ours with attractive prices, but they are not designed for on-highway vehicles or require special modifications at time of installation by the OEM. For your customers safety, your liability and the safety of others on our highways, please ensure the parts you're installing are in compliance with FMVSS-124.

All our air throttle parts are in compliance with the Federal Motor Vehicle Safety Standard (FMVSS) 124 for on-highway vehicles.

Choose from two treadle assemblies,
Surface mounted or through the floor.

When the pedal is applied, the treadle regulating valve delivers an output proportional to the pedal position. The output controls a valve on the throttle control assembly which positions the engine's throttle lever.
Two models of treadle to chose from!
Surface Mounted Treadle.........OR..........Through The Floor Mounted Treadle

Surface Mounted Treadle

Through the Floor Mounted Treadle
Depending on your application, choose from the following parts to complete the install.

The pneumatic throttle control assembly is used to position an engine's throttle lever in response to an air pressure signal from the treadle valve. The assembly contains a throttle cylinder, mounting bracket, throttle lever and spring. The mounting bracket installs the cylinder on the limiting speed governor of a Detroit Diesel V-71 or V-92TT series engine.

The external spring is provided for compliance with FMVSS-124 requirements. It returns the throttle lever to idle in the event of internal spring failure. The mounting plate is designed to mount in two positions using the governor housing top plate bolts.

 A simple bolt on installation.
Pneumatic Throttle Control Assembly.

If you have an application other than a Detroit Diesel V-71 or V-92TT series engine, we have a solution for you. The General Purpose Throttle Control! The lever on this unit has multiple holes for easy connection to a variety of throttle linkages. This unit is supplied with a rod end (1/4-28 female thread) secured with a bolt and nut in the lever assembly.

General Purpose Throttle Control

This unit replaces the mechanical modular on the Allison  AT-540, CLT-750, HT-750CRD, MT-640, CLBT-750, HT-740, HT-750DRD, MT-650 AND V-730 transmissions. When an air throttle is used on a vehicle with an Allison transmission, the transmission modulator provides the transmission with a signal proportional to the throttle position in order to control the transmission shift pattern.

Pneumatic Transmission Modulator.

Some applications require a lever, our Panel Mounted Lever Control may be the ticket. This unit works well with the General Purpose Throttle Control.

It is actuated by a handle which is equipped with adjustable stops so the operator can establish minimum and maximum pressure limits within the output range. When the stops are adjusted to allow maximum handle movement, the valve modulates through its entire output range and the handle has a rotation of 90 degrees. The unit also features a friction adjustment which restricts or allows free movement of the handle.

Panel Mounted Lever Control


If you have a manual transmission, choose a Treadle (Through-the-floor or Surface mount), add a   Pneumatic throttle control assembly, if installing on a Detroit 6V92, 8V71 or 8V92. Other makes of engines, use our General Purpose Throttle Control.

If you have an automatic transmission, add a Pneumatic transmission modulator.

All components includes instructions and part list.
* Fittings and air line not included.
* Prices are subject to change.

When ordering, please specify transmission model and surface or through the floor mount treadle.

To order call Coach Conversion Central Products
916 929-3815

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