Jacobs Exhaust Brake®
The new Cummins 600 Turbo Diesel has been named one of the 10 Best Engines for 2004*, and the best brake for the best engine comes from Jacobs, the world leader in engine braking and retarding technology.

The Jacobs Exhaust Brake, from the legendary Jake Brake family of products, is the only exhaust brake that Mopar endorses for your Dodge Ram. It transforms horsepower into braking power by using a butterfly valve in the exhaust system. When activated, this valve restricts the exhaust gas flow and increases backpressure in he engine, slowing down your Dodge Ram pickup and reducing brake wear. In fact, it can help your brakes last up to three times longer for significant maintenance savings.

New for 2003 is the Jacobs Exhaust Brake Kit. This includes and easy to use fingertip control on/off switch mounted right on the gearshift for increased driver convenience and safety. And a belt-driven vacuum-pump system exclusively designed by Cummins is used to actuate the new exhaust brake. Also, there is more peak braking horsepower than on the previous Cummins 24-valve engines. A larger-diameter brake housing is designed to match the new low-restriction 4" exhaust system on 2004-1/2 Dodge Ram trucks. Plus, the Exhaust Brake by Jacobs includes a drilled and tapped port for installation of an optional pyrometer**, which allows you to monitor exhaust gas temperatures. Of course, the Jacobs Exhaust Brake is available for older Dodge Ram Heavy-Duty models as well (see chart below).

Plus, there's a great side benefit: Start up the engine and idle with the exhaust brake switch in the on position, and the Jacobs Exhaust Brake will help your engine reach operating temperature twice as fast - while helping you conserve fuel after the warm up process.

In addition, the Jacobs Exhaust Brake comes with a comprehensive 3-year/100,000-mile (160,935 km) warranty on the exhaust brake assembly and a 3-year/36,000-mile (57,937 km) warranty on all other kit components.

Exhaust Brake FAQs
Jacobs Literature for ISB 5.9 Exhaust Brake

Part #
Part #
1989 - 1993 3804848, 3814854 N/A
1994 - 1998 3804848 N/A
1998-1/2 - 2002 3800780 8205577
2003 - 2004 4089427 82208277
2004-1/2 4089598 82208835

*Jacobs is a trademark of Jacobs Vehicle Systems.
**Pyrometers are available from independent parts suppliers.