Trailer brakes
Ram's towing guide says trailers above a set loaded weight must have their own brakes, and state rules also set thresholds. Electric trailer brakes need a brake controller in the truck, set up for the loaded trailer.
Exhaust brake
Many Cummins Rams have an exhaust brake that uses the variable-geometry turbo to create back-pressure and slow the truck. Ram recommends using one when towing. It saves the service brakes on long grades but does not replace them.
On grades
- Pick a lower gear before the descent.
- Watch coolant and transmission temperatures on climbs.
- Leave more following distance than you think.
Where this comes from
- Ram Trucks: Towing basics (PDF)
- Cummins service information: VGT actuator, electric (troubleshooting)
- CumminsForum: No exhaust brake, VGT actuator position (owner thread)
- NHTSA interpretation: trailer hitch and towing ratings
- DieselHub: Chrysler/Dodge 48RE transmission
Last reviewed 2026-10-19. General information only: your owner's manual and service information come first.