2018 RAM 2500 brakes problems

The hydraulic control unit that manages ABS function fails intermittently or permanently, disabling anti-lock braking and traction control. Owners report the ABS and traction control warning lights illuminating, sometimes flashing on and off repeatedly, along with audible warning chimes every 10-15 seconds or more frequently. The HCU is part 68143491AA (defective) with a redesigned replacement 68143491AB. Failures occur at mileage ranging from under 10,000 miles to 100,000+ miles, with multiple owners experiencing repeated failures within 13,000 to 25,000 miles after initial replacement. One owner reported the motor brushes inside the HCU became stuck in the brush holders, causing intermittent electrical contact loss.

When: Failures reported from under 10,000 miles to 100,000+ miles; repeated failures within 13,000–25,000 miles after initial repair

Symptoms owners cite: ABS warning light illuminating intermittently or permanently; Traction control warning light on; Service Electronic Braking System warning message on dash; Audible warning chimes/dings when lights are active, sometimes every 10–15 seconds or 20+ times per minute; Cruise control becomes inoperative when ABS light is on; Loss of ABS function; vehicle brakes lock up under hard braking instead of pulsing; Warnings triggered by rough roads, bumps, potholes, or random events; Brake pedal sometimes goes nearly to the floor before engagement; Intermittent failures that may clear temporarily

Codes mentioned: C0020, C0020-01, C2200-49, C0090-01

Repairs/costs cited: Replacement of hydraulic control unit part 68143491AA (defective). Repair costs cited range from ~$800 to ~$2,000, including diagnostics ($112–$297), parts, and labor. One owner paid $1,700 at ~25,000 miles. Multiple owners report replacement parts are on national backorder—wait times of 6–12+ months cited; several mention being told parts are discontinued or under engineering redesign. Some dealers ordered the newer 68143491AB part but cannot find it in stock. One owner fabricated a repair by freeing stuck motor brushes but could not reassemble the unit without special tools. Dealership diagnostic fees charged even when issue is known.

Recalls/TSBs owners mention: RAM/Stellantis issued recall C4B (later referenced as NHTSA 24V896000 and 24E-100) for brake hydraulic unit failures in late 2024/early 2025, but parts are not yet available. Owners received recall notices stating 'no remedy currently available' and were advised to contact dealers when parts arrive. Technical Service Bulletin (TSB S2005000004) exists for this issue. A class action lawsuit was active against FCA/Stellantis (mentioned in multiple complaints) alleging breach of warranty and use of defective materials. One owner in Alaska was denied participation in a California-based class action. RAM customer care and Chrysler customer care have acknowledged the known issue but offered limited assistance (e.g., one month car rental, declining warranty coverage). Dealers report FCA/Mopar blocking parts orders and requiring additional diagnostic steps before parts release. One owner reported Mopar parts available on Amazon and eBay despite official unavailability claims.

The ABS control module experiences internal electronic failure, sometimes related to motor brush deterioration. One professional diagnostic technician identified the root cause as brushes sticking in brush holders inside the motor assembly of the hydraulic pump, leading to open-circuit faults. This sticking is more likely to occur when the vehicle hits bumps, causing the commutator to move away from the stuck brushes and break electrical contact.

When: Failures reported at various mileages; second occurrence typically 18 months to 2+ years after first failure

Symptoms owners cite: ABS and traction control warning lights illuminating intermittently or staying on; Warnings triggered especially when hitting bumps or rough road; Cruise control disabled when lights are active; Audible warning chimes; Loss of ABS and traction control function

Codes mentioned: C0020, C0020-01

Repairs/costs cited: Replacement of ABS control module/pump. One owner paid $798.15 for repair at 44,181 miles. Parts also on backorder; wait times 6–12+ months reported.

Recalls/TSBs owners mention: Technical Service Bulletin (TSB S2005000004) documents the brush sticking issue. Redesigned part 68143491AB is mentioned but unavailable. Recall C4B/24V896000 addresses this. One owner requested warranty assistance via RAM Customer Care and was denied.

While braking hard—especially during emergency situations, in wet conditions, while towing, or on rough roads—the ABS system fails to engage, brakes lock up uncontrollably, and the vehicle skids or slides rather than maintaining steering control. One owner reported slamming brakes while pulling a trailer and the vehicle crashed despite the braking effort. Another lost almost all brake pressure while exiting a highway at high speed. A third heard a grinding sound from front wheels, then felt a clunk through the brake pedal and the pedal went to the floor, causing the vehicle to roll across the street.

When: Occurs during emergency braking or while driving in wet/adverse conditions; also during towing

Symptoms owners cite: Loss of ABS function during hard braking; Brakes lock up instead of pulsing; Vehicle skids or slides uncontrollably; Extended braking distance; Brake pedal goes to the floor; Grinding noise from front wheels (one case); Brake pedal 'kick back' when depressing brakes

Codes mentioned: C0020, C0020-01

Repairs/costs cited: Root cause is HCU or ABS module failure. One owner reported a front driver-side brake line burst one month after HCU failure was first diagnosed, repaired at owner's expense; possibly related to higher-than-normal pressures caused by HCU malfunction.

Recalls/TSBs owners mention: Recall C4B/24V896000 issued but remedy not available. One owner involved in a crash was told the vehicle was included in the recall but parts were not yet available; manufacturer offered no assistance beyond acknowledging the recall. Dealers advised owners not to drive in wet/heavy-traffic conditions or while towing until repairs could be made.

After initial repair—even with OEM Mopar parts—the exact same HCU or ABS module fails again within a short service interval, sometimes with fewer than 13,000 miles on the replacement part. One owner had three failures within 12,000 miles total (28k, 36k, 40k miles). Another had failures at 25,000 miles, then again at 50,000 miles (25,000 miles after first replacement). A third replaced the HCU in 2022 at 25,392 miles, but the replacement part was the same (older) version 68143491AA rather than the redesigned 68143491AB, and failed again after 13,000 miles. One owner had ABS failure in 2020 (24,433 miles), repaired under warranty, then failed again in 2024 (44,181 miles)—same part replaced both times.

When: Second failure typically occurs 13,000–25,000 miles after first repair; some failures within months

Symptoms owners cite: Identical symptoms to initial failure: ABS and traction control lights, warning chimes, loss of ABS function, cruise control disabled

Codes mentioned: C0020, C0020-01

Repairs/costs cited: Dealerships replace the same defective part 68143491AA instead of the redesigned 68143491AB. Second repair often not covered by warranty (24-month limit on parts, or warranty expired). Cost for second repair $798–$1,000+. One owner was told by dealership that the HCU part was being redesigned and all old parts were removed from inventory.

Recalls/TSBs owners mention: Dealers acknowledged the pattern but offered limited solutions. One owner was warned the second failure might require further diagnostics ($296) before ordering parts, even with video evidence of the problem. Warranty claims were denied on second occurrences citing warranty expiration. No manufacturer buyback or extended warranty program mentioned.