A dedicated engineering staff provides production support, development of technology insertions, and new product development for our powertrain components. The engineering staff supporting these products are also engaged in introducing product improvements through design and technology insertion in current production components and developing new products.

The team is also developing a new fuel delivery and head design for a diesel engine providing better performance, efficiency, and emissions. The GEP engineering development team is skilled and experienced at understanding and providing solutions to our customers' demanding requirements.

Optimizer 6500®-290 — 160 hp / 290 lb.-ft.

Naturally-aspirated and mechanically controlled

Optimizer 6500®-380 — 190 hp / 380 lb.-ft.

Turbocharged and mechanically controlled

Optimizer 6500®-410 — 205 hp / 410 lb.-ft.

Turbocharged and mechanically controlled

General Transmission Products

The 4L85E transmission is a close-ratio four-speed automatic transmission that serves the heavy-duty service market, including AM General's Humvee, full-size vans, shuttle buses, delivery trucks and light motor homes.

The transmission has been refined and improved over 18 years, has been used in Humvee vehicles for 15+ years and continues to provide reliable performance on extreme terrain and climate conditions.
Incorporating electronic control modules, the 4L5E transmission provides consistent and precise shift points and shift quality.

These controls continuously monitor shift timing, internal and external conditions and adjust shifts for consistency. Shift stabilization limits the amount of hunting between gears when traveling through mountains, with or without a trailer.