2019-2024 Ram 6.7L Cummins Brake Parts

Brakes on the 2019-2024 Ram 6.7L Cummins

The 2019 redesign of the fifth-generation Ram Heavy Duty brought a new brake system along with the new frame and the new 6.7L Cummins. Ram fitted larger twin-piston pin-slider calipers front and rear, a new booster, a new master cylinder and a larger-ratio pedal swing. Front rotors measure 14.17 x 1.54 in and rears 14.09 x 1.34 in, with ABS. Diesel 2500s and all 3500s use hydro-boost, where pressure from the power-steering pump assists the pedal. Gas 2500s use a vacuum booster instead. In testing, Car and Driver stopped 2019 trucks from 70 mph in 203 to 206 feet.

The Cummins gives you a second way to slow down. The Holset variable-geometry turbo doubles as an integrated exhaust brake, with a smart mode that holds a downhill speed you set. A factory trailer brake controller was offered as an option and is part of the Max Tow package.

What fails and why

The brake issues recorded for this generation fall into a short list. Some are recalls, some are software, and some are owner reports worth knowing about.

• Caliper seal recall. Recall 19V-635 covered some 2019 Ram 2500/3500 calipers assembled with the wrong assembly fluid, which made the rubber seals swell. The result was dragging or soft brakes on nearly new trucks.
• Soft pedal and lost assist. Owners of 2019-2021 trucks have reported a spongy pedal with extra travel and no warning lamps. One 2020 3500 owner reported a hydro-boost pump port tube that failed, dumped power-steering fluid and took out steering assist and brake assist at the same time. These are owner reports, not a recall, but they show why the steering side deserves attention.
• ABS and stability lights. Software recall 22V-140 covered the ESC malfunction lamp on 2019-2022 2500 and 3500 cab chassis under 10,000 lb GVWR, and 24V-415 covered 2022 2500/3500 trucks where the ABS module could disable ESC. A warning light is not always a hardware failure.
• Caliper bolts after a brake job. A 2020 3500 owner reported front caliper mounting bolts backing out repeatedly after service. On calipers this heavy, torque the bracket bolts to spec and use thread-locker every time.
• A fading exhaust brake. When the exhaust brake gets weaker, look at the turbo before the brakes. It is an early turbo-vane symptom, not a service-brake fault.

Stock replacement vs. upgrade

For a truck that tows and hauls, the factory layout is the target. Pads and rotors should match the 14.17 in front and 14.09 in rear factory discs and the twin-piston calipers. Fresh fluid, clean hardware and correct bolt torque do more for a heavy Ram than any single bolt-on. Keep the hydro-boost healthy too: power-steering fluid condition and pump output both affect brake assist, so a steering-pump service doubles as brake maintenance on a diesel Ram. The upgrades on this page are practical ones: extended front lines for lifted trucks and billet covers for the master cylinder.

What we carry

This collection covers the service supplies and hardware a brake job on these trucks calls for:

• Lucas Oil DOT 3 and DOT 4 synthetic brake fluid, non-chlorinated brake parts cleaner, and contact cleaner for electrical connectors.
• Wehrli Custom Fabrication (WCFab) billet aluminum brake master cylinder cap and a master cylinder reservoir cover, both listed for 5.9L and 6.7L Cummins Rams.
• BDS Suspension front brake line set for 4WD 6.7L Cummins trucks with 4 to 8 inches of lift.

For engine, fuel and drivetrain parts, start at our Cummins hub.

Fitment notes

Master cylinders and boosters do not cross the Ram HD engine line: the gas 2500 runs a vacuum booster while the diesel 2500 and every 3500 run hydro-boost. On a 3500, the dually rear hubs and axle differ from single-rear-wheel trucks (12-in versus 11.5-in axle), so confirm rear rotor and hub parts by SRW or DRW and by Max Tow package. The BDS line set is listed for 4WD trucks only, so check its listed model years against yours. Use the brake fluid type your owner's manual specifies. When in doubt, verify by VIN.

Frequently asked questions

Why does my Ram 3500's brake pedal feel soft when the pads are good?

On a diesel Ram, brake assist comes from hydro-boost, which is driven by the power-steering pump. Low or worn-out steering fluid, a weak pump or a leaking hydro-boost line can all cut assist, and owners have reported soft, long-travel pedals on 2019-2021 trucks. Check the steering side before you replace calipers.

Was my 2019 Ram 2500 part of a brake recall?

Some 2019 Ram 2500 and 3500 trucks were covered by recall 19V-635 for calipers assembled with the wrong assembly fluid, which swelled the seals and caused dragging or soft brakes. Run your VIN through the NHTSA recall lookup or ask a Ram dealer whether the work was completed.

Can I use a gas Ram 2500 master cylinder on my Cummins truck?

No. The gas 2500 uses a vacuum booster, while the diesel 2500 and all 3500s use hydro-boost, so master cylinders and boosters do not interchange across engines. Order by engine and confirm by VIN.

Do I need different brake lines after lifting my Ram?

If you have lifted a 4WD truck 4 to 8 inches, the BDS Suspension front brake line set in this collection is made for that range. After installation, cycle the suspension and turn the steering lock to lock to confirm the lines clear everything.

My exhaust brake is weaker than it used to be. Is that a brake problem?

Usually not. The exhaust brake on this engine is built into the variable-geometry turbo, and a weakening exhaust brake is an early sign of turbo-vane trouble rather than a service-brake fault. Have the turbo looked at before you touch pads or rotors.

Not sure what fits? Call the shop at the number in the header, or use the fitment checker on any product page. We install everything we sell.