CORE – HEATER
full bulletin at NHTSA ↗2021 Jeep Gladiator engine problems
severe Owners of the 2021 Jeep Gladiator have filed 15 NHTSA complaints about the engine at roughly $3,100 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Complaints
15
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2020 Gladiator | 25 |
| 2021 Gladiator (this page) | 15 |
| 2022 Gladiator | 5 |
1fire
1injury
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
CORE – HEATER
full bulletin at NHTSA ↗BOLT - HEX FLANGE HEAD
full bulletin at NHTSA ↗Check Engine Light (CEL) Illuminated with Diagnostic Trouble Code (DTC) P0106 Manifold Absolute Pressure Sensor Performance Setting In The Powertrain Control Module (PCM)
full bulletin at NHTSA ↗Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● **P0111-00 - Intake Air Temperature Sensor 1 Circuit Range Performance Bank 1. (In Active or Stored status) ● P0071-00 - Ambient Air Temperature Sensor Performance. (In Active or Stored status) ● P0072-00 - Ambient Air Temperature Sensor Circuit "A" Low. (In Active or Stored status) ● P0073-00 - Ambient Air Temperature Sensor Circuit "A" High. (In Active or Stored status) ● P0011-00 - Bank 1 Camshaft 1 Position Timing Over Advanced Or. (In Active or Stored status) ● P2
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The 2021 Gladiator's 3.0L EcoDiesel shows a pattern of thermal and drivetrain failures. Owners report that under towing (even within capacity), highway cruising, or ambient temps above 80°F, the engine derate limiter kicks in hard—cutting speed to 35–50 mph at 248–265°F oil/coolant temps—forcing unsafe roadside pulls and delaying highway merges. The root cause cited by owners: Jeep removed the oil cooler and larger pan used in prior Ram/Grand Cherokee EcoDiesels, leaving no factory fix a year into production.
Valve train problems are emerging: right intake camshaft and rocker arm failures at 25,000–66,000 miles trigger misfires and limp mode during acceleration or climbing. Advanced Auto reports three recent Gladiators with the same camshaft failure. Jeep released a redesigned kit and oil-pressure software upgrade but 12,000+ orders are backlogged.
Idle and throttle controls misbehave: throttle bounces 500–1500 rpm off idle without driver input, and the auto start/stop system engages and disengages opposite to the owner's manual. Dealerships have reproduced both faults then falsified records claiming duplication failed; FCA technical advisors call malfunctions "operating as designed."
One owner's vehicle caught fire at 20,000 miles; Jeep retrieved it for inspection but never disclosed the cause. Stalling at idle with clutch engaged also occurs. Owners stress these are not isolated: forums and Facebook groups show thousands discussing the same cooling and derate issues.
Same Jeep Gladiator engine reports on nearby years: 2020
Failure modes owners describe
Thermal Derating Under Load
Engine loses power and limits vehicle speed to 15–50 mph when coolant or oil temperatures climb under towing, higher grades, highway speeds, or warm ambient conditions. Issue repeats across multiple Gladiator EcoDiesel owners. Owners report the 3.0L EcoDiesel was redesigned for Gladiator/Wrangler with oil coolers and larger oil pans removed versus prior Ram/Grand Cherokee installations, causing sustained high oil temperatures. Speed restriction occurs at 248–265°F coolant/oil temps.
When: 5,000 miles onward; first reported May 2021 after 5,000 miles; occurs 20+ times within 14 months at 23,000 miles total; any ambient above ~80°F, especially >100°F; consistently during towing, grades, or highway cruising.
Symptoms owners cite: Power loss and automatic speed derating to 10–50 mph; Coolant temp gauge reads 248–265°F; Engine speed limiter engaged without warning; Worse with AC on; Gauge not linear; vehicle nearly overheating before gauge shows rise; Requires engine to cool at fuel stops to resume highway merge speeds
Repairs/costs cited: No factory fix approved; owners report aftermarket oil cooling solutions exist but are ineffective due to space constraints in engine bay; dealer has not successfully diagnosed or corrected issue.
Idle Surge and Throttle Bounce
Throttle surges and bounces off idle 500–1500 rpm above driver intent, particularly after releasing accelerator and engaging clutch. Issue reproduced by dealership service personnel and 4 independent shops but deemed 'operating as designed' by FCA Technical Advisor. Malfunction falsely documented as unduplicated by dealership; service records backdated and falsified.
When: Occurs frequently but not consistently; observed during normal driving and in all gears and neutral.
Symptoms owners cite: Throttle bounces and surges 500–1500 rpm without driver input; RPMs drop slowly to idle, then surge; Occurs with or without foot on brake; Affects shifting, acceleration, and braking operations; Distracts driver; induces confusion about accidental pedal input
Recalls/TSBs owners mention: FCA Technical Advisor claimed vehicle 'operating as designed' both when issue could not be replicated and when it could—a contradiction. Dealership falsified service records.
Erratic Auto Start/Stop System
Auto Start/Stop activates and deactivates contrary to owner's manual specifications and HVAC settings. Engine auto-stops when defrost is turned off (opposite of documented behavior) and auto-starts when defrost is below maximum setting (contrary to manual stating start only at full defrost). No 'STOP/START READY' message appears before unintended stops. Reproduced by dealership service and 4 independent shops; FCA Technical Advisor claims 'operating as designed' despite manual contradiction.
When: Occurs during normal driving; no specific mileage or temporal pattern noted.
Symptoms owners cite: Unexpected engine auto-stop in traffic when defrost deactivated; Unexpected engine auto-start when defrost below full setting; No 'STOP/START READY' message before auto-stop; Behavior contradicts owner's manual; Creates driver confusion and distraction; potential for rear-end collision or unintended vehicle rollover
Recalls/TSBs owners mention: FCA Technical Advisor claimed system 'operating as designed'; contradicts owner's manual documented behavior.
Engine Stall at Idle with Clutch Engaged
Vehicle randomly stalls while idling with clutch pedal fully engaged. Witnessed and documented by independent mechanic; dealership and FCA Technical Advisor state 'operating as designed' and 'normal characteristic,' implying intentional design.
When: Occurs randomly; no specific mileage or condition pattern stated.
Symptoms owners cite: Random stall while idling with clutch fully engaged; Creates serious safety hazard at traffic lights or while driving; Risk of rear-end collision in heavy traffic
Recalls/TSBs owners mention: Dealership and FCA TA claim 'operating as designed' and 'normal characteristic.'
Camshaft Failure and Valve Train Damage
Right intake camshaft and roller rocker arm failed, causing misfires and limp mode activation during acceleration and climbing grades. Advanced Auto reports this is the third 2021 Gladiator with camshaft failure in their shop recently. Jeep/Stellantis redesigned kit and upgraded software to increase oil system pressure but parts supply is critically short; 12,000 orders backlogged. Another report lists failed camshaft with engine oil cooler housing requiring replacement at 25,000 miles.
When: 66,000–98,000 miles; one failure at 25,000 miles.
Symptoms owners cite: Camshaft failure (right intake or general); Roller rocker arm failure; Multiple cylinder misfire (cylinders 2, 4, 6 reported); Flashing check engine light; Limp mode activation on acceleration and hill climbing; Engine makes excessive noise from passenger side; Inability to safely pass; vehicle undriveable for 45+ days
Codes mentioned: P0300 (multiple cylinder misfire), Camshaft 1 position slow responding, P0303 (cylinder 3 misfire), P0305 (cylinder 5 misfire)
Repairs/costs cited: Jeep/Stellantis released redesigned camshaft kit and software upgrade to increase oil system pressure; parts backordered with 12,000+ orders pending. Engine oil cooler housing replacement required in at least one case.
Recalls/TSBs owners mention: Redesigned kit and software upgrade released but parts critically backlogged; no field recall or expedited replacement program noted.
Engine Fire
Vehicle caught fire while driving at 60 mph; white smoke filled engine compartment and interior before flames engulfed front end. Local emergency services extinguished fire; vehicle totaled. Manufacturer retrieved vehicle for inspection but provided no cause determination to owner; injuries reported (contact's father suffered minor burns to both hands).
When: Approximately 20,000 miles.
Symptoms owners cite: White smoke from engine compartment; Smoke permeating interior; Complete front-end fire engulfment; Unknown warning lights illuminated
Repairs/costs cited: Vehicle totaled; towed to residence.
Recalls/TSBs owners mention: Manufacturer opened case, retrieved vehicle for inspection, returned vehicle without providing cause determination to owner.
Synthesized from 15 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 0 most recent
Had engine trouble with your 2021 Jeep Gladiator?
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 engine problem on the 2021 Jeep Gladiator?
It's a meaningful issue. 15 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $3,100.
At what mileage does the engine typically fail?
Based on the 15 complaints filed, engine issues most often appear around 47,667 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 $3,100 for engine 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 engine?
No active recalls currently cover engine 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/2021/Jeep/Gladiator.
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.