Cruise control on 65mph going down hill. Transmission dropped into a lower gear. Vehicle immediately slowed down immediately by probably 20-30 mph. Everything in vehicle was thrown forward. I struggled to keep control and thought I was going to roll and crash off of roadway, or hit another vehicle. This was not a problem for two years, until June of this year. Driven the same stretch of highway…
2018 RAM 1500 cruise control problems
severe 13 complaints filed with NHTSA · avg repair $600 · see cruise control across all vehicles →
Complaints
13
Recalls
0
Avg fix
$600
1crash
2injuries
What stands out
No new NHTSA cruise control complaint has been filed on this vehicle in over 4 years — the issue may be aging out of the active population.
The failure pattern owners describe
Buyer takeaway: Multiple 2018 RAM 1500 owners report dangerous electronic control failures: unintended acceleration that dealers can't fix, cruise control that doesn't work reliably, abrupt downshifts on hills that throw passengers forward, and limp-mode derates from DEF/DPF codes happening weekly. Some vehicles were repurchased as lemons; dealers offer no lasting solutions.
Owners of the 2018 RAM 1500 describe a cluster of electronic control failures affecting throttle, transmission, and cruise function—most without warning lights or dealer-reproducible diagnosis.
Unintended acceleration is the most serious complaint. Multiple owners report the throttle sticking open or the vehicle accelerating without input, even with the brake pedal pressed. One owner accelerated to 60 mph on a rural road and couldn't stop; another had the vehicle accelerate twice during low-speed parking and driveway maneuvers, striking a person. One owner experienced prolonged lag between pedal input and response, dangerous when merging.
Cruise control operates intermittently or not at all. Some owners report the button only works 50% of the time; others can't engage it no matter how hard they press, even 50 times. When ABS or traction control lights activate, cruise disables.
On descents, cruise control causes transmission to drop into a lower gear without warning, decelerating from 65 to 30 mph in seconds—hard enough to throw passengers forward. The transmission grinds and strains until the driver brakes. RAM dealers acknowledged this on test but dismissed it as a "temporary slight speed change."
DEF and DPF codes trigger limp mode repeatedly, with vehicles dropping from highway speed to 30–40 mph. Owners report one or more codes per week, with dealer reprogramming failing to resolve the pattern.
Cold-start throttle hesitation on the Eco Diesel is severe—owners can't safely cross a 55 mph highway. Dealers and RAM customer service offered no fix. ABS control module failures disable cruise and braking features; Stellantis has the replacement part on backorder and "engineering review."
Same RAM 1500 cruise control reports on nearby years: 2015 · 2016 · 2017 · 2019 · 2021
Failure modes owners describe
Unintended acceleration / throttle control loss
Throttle sticks open or vehicle accelerates without driver input, even with brake applied. Owners report losing control during normal driving and parking maneuvers.
When: 2,400–20,000 miles; ongoing throughout ownership
Symptoms owners cite: Vehicle accelerates to 60 mph on rural road despite releasing accelerator; Vehicle continues accelerating even with brake pedal pressed; Acceleration during low-speed garage/driveway entry with brake depressed; No response to normal throttle inputs when attempting to accelerate from stop; Long lag between pedal input and vehicle response
Codes mentioned: Throttle error light (temporary), Electronic throttle control fault
Repairs/costs cited: Dealerships unable to diagnose or replicate; one vehicle deemed lemon and repurchased by FCA
Recalls/TSBs owners mention: RAM customer assist offered only free oil changes; no technical remedy provided
Cruise control engagement failure / intermittent operation
Cruise control button does not engage, or engages unpredictably. Owners report having to push the button repeatedly with no result.
When: From new; first observed around 26,000 miles for some units
Symptoms owners cite: Cruise engages only 50% of the time; Button press does not activate cruise, regardless of speed or pressure applied; Cruise disables when ABS/traction control lights activate; Button requires multiple presses to activate
Cruise-control downshift on descents causing sudden deceleration
While cruising downhill, transmission drops to lower gear unexpectedly, causing abrupt speed loss (20–35 mph in seconds). Creates unsafe situation where loose items and passengers are thrown forward.
When: At 21,000 miles; occurred repeatedly on same roadway sections
Symptoms owners cite: Transmission drops into lower gear while descending at cruising speed (65 mph); Grinding or clunking noise from transmission during shift; Sudden deceleration of 20–30 mph within seconds; Vehicle stays in lower gear straining until brake is pressed; No warning light or indicator before failure
Repairs/costs cited: RAM tech reproduced problem at lower speed (25–30 mph); dealer blamed 'temporary slight speed change,' refused to acknowledge safety risk
Recalls/TSBs owners mention: RAM dealer acknowledged reproduction of issue but dismissed as 'temporary' and 'slight speed change'
DEF/DPF system codes causing limp mode and engine derate
Repeated diagnostic trouble codes related to DEF and DPF systems trigger limp mode, forcing vehicle into 30–40 mph derate without warning. Pattern recurs weekly over months.
When: Ongoing over 6+ months; mileage not specified
Symptoms owners cite: Multiple codes in 6-month period affecting electronic throttle control; Vehicle enters limp mode and drops from 70 mph to 30–40 mph; DPF filter full with no active regeneration; Repeating codes despite dealer reprogramming attempts; No warning of imminent code before failure
Codes mentioned: DPF (diesel particulate filter) codes, DEF (diesel exhaust fluid) system codes
Repairs/costs cited: Dealer attempted reprogramming without success; repairs and root cause unclear
Cold-start throttle hesitation / slow response
Eco Diesel engine hesitates severely when cold, creating dangerous acceleration lag. Owner cannot safely merge across 55 mph highway after work.
When: From new; occurs every day vehicle is driven in cold conditions
Symptoms owners cite: Significant hesitation during cold engine acceleration; Unable to cross multi-lane highway at posted 55 mph speed due to sluggish response; Problem persistent despite latest engine control software update
Recalls/TSBs owners mention: RAM customer assist and dealer offered only free oil changes; stated 'nothing can be done'; customer assist promised to relay to engineering but no follow-up
ABS/traction control module failure
ABS control module failure triggers warning lights and disables cruise control. ASE mechanic confirmed need for module replacement. Stellantis has part on engineering review and backorder status.
When: Mileage not specified
Symptoms owners cite: ABS control module light illuminates; Traction control system light illuminates; Electronic trailer brake system light illuminates; Cruise control disabled when lights activate
Codes mentioned: ABS control module fault, Traction control system fault, Electronic trailer brake system fault
Repairs/costs cited: ABS control module replacement required; part on backorder
Recalls/TSBs owners mention: Stellantis part on 'engineering review' and backorder; no recall issued despite known issue across multiple RAM vehicles
Power steering loss
Power steering stopped working during normal driving after warning light illuminated.
When: After 1 mile of driving post-warning light
Symptoms owners cite: Power steering indicator light illuminated; Power steering system stopped functioning
Codes mentioned: Power steering indicator light
Synthesized from 13 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
Had cruise control trouble with your 2018 RAM 1500?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the cruise control problem on the 2018 RAM 1500?
It's a meaningful issue. 13 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $600.
At what mileage does the cruise control typically fail?
Based on the 13 complaints filed, cruise control issues most often appear around 18,280 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $600 for cruise control repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to cruise control?
No active recalls currently cover cruise control issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2018/RAM/1500.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.