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RAM · Known Issues

2020 RAM 3500 Problems: 7 Known Issues

2020 model year · 6,650+ owner reports · Updated September 2026

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Issue summary

According to Au7o's analysis of 6,650+ owner reports, the 2020 RAM 3500 has 7 documented known issues, with 2 rated critical. The most serious are Aisin AS69RC Transmission Overheating and Converter Shudder ($300-$3,500 repair) and AAM 11.5/11.8 Front Axle Seal and U-Joint Failure ($200-$1,200 repair). The most commonly reported issue is Aisin AS69RC Transmission Overheating and Converter Shudder with 2,800 owner reports. Across all issues with published estimates, repair costs range from $50 to $4,000. DIY maintenance guides at au7o.io.

In This Article

  • 3500 Transmission1
  • 3500 Drivetrain1
  • 3500 Electrical2
  • 3500 Engine1
  • 3500 Exhaust1
  • 3500 Suspension1
  • Recalls22
  • FAQ
Get Started
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In This Article

  • Transmission1
  • Drivetrain1
  • Electrical2
  • Engine1
  • Exhaust1
  • Suspension1
  • Recalls22
  • FAQ

All 7 Known Issues

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ALL YEARS2025202420232022202120202019201820172016201520142013201220112010200920082007
Community reported
2,800 owners

On the 2013-2025 RAM 3500, the RAM 3500 equipped with the Aisin AS69RC 6-speed automatic transmission experiences torque converter shudder, overheating when towing, delayed shifts, and premature wear. The torque converter lockup clutch develops a shudder at light throttle and highway speeds. When towing heavy loads (10,000+ lbs), the transmission temperature can spike rapidly, triggering limp mode. TSB 21-013-19 addresses torque converter shudder with updated fluid and converter. The AS69RC uses a specific Aisin fluid (Mopar 68218058AA) and using incorrect ATF+4 causes accelerated wear. Converter replacement runs $2,000-3,500.

This issue also affects: Chrysler 200, Chrysler 300M, Chrysler LHS

Common Symptoms

  • Shudder or vibration at highway speed (40-60 mph)
  • Transmission overheating when towing
  • Delayed or harsh shifts
  • Transmission temperature warning light
  • Limp mode activation while towing
  • Slipping sensation during light acceleration
  • Torque converter lock/unlock cycling

How to Fix

For shudder: First try a complete fluid change with Mopar Aisin-specific ATF (68218058AA) - NOT standard ATF+4. If shudder persists, torque converter replacement is needed ($2,000-3,500). Check TSB 21-013-19 for updated converter part number. For overheating: Install an auxiliary transmission cooler ($200-400, B&M or Derale) and reduce towing speed. Ensure the external transmission filter (if equipped) is clean. Some 2013-2018 trucks qualify for extended warranty coverage on the Aisin transmission.

What you need to fix it

Only diagnosis- and fitment-reviewed repair parts are linked here.

  • Genuine Mopar ASRC transmission fluid 05189966AF

    AS69RC/AS68RC/AS66RC applications specifying 05189966AF or supersession; verify transmission and package quantity.

    Tasca Parts
  • Genuine Mopar 68224232AA AS69RC transmission filter

    2013-2018 Ram 3500 high-output 6.7L Cummins with AS69RC as listed; not Ram 2500 and not approved here for 2019-2025. Fitment/availability: In stock at review

    XDP

As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

Typical repair cost:$300 - $3,500

Research This Issue

Based on 2,800 owner reports

GoogleRedditYouTubeNHTSA
Community Reported
High Confidence2,800 owner reportsLast reported by owners Feb 2026Reviewed Feb 2026
Community reported
1,650 owners

On the 2013-2025 RAM 3500, the RAM 3500 4x4 with the AAM (American Axle Manufacturing) 9.25 front axle experiences premature front axle seal leaks and u-joint failures. Differential fluid leaks from the inner axle seals, contaminating the front brakes. The front axle u-joints (Dana Spicer 60) wear out prematurely, especially on trucks with oversized tires or that are used for snow plowing. Symptoms include grease on the inner wheel/brake area, clicking/popping when turning in 4WD, and vibration. TSB 03-004-18 addresses front axle seal replacement procedure. If the leaking oil reaches the brake pads, both pads and rotors must be replaced.

Common Symptoms

  • Gear oil leak on inside of front wheels
  • Contaminated front brake pads (oil soaked)
  • Clicking or popping noise when turning in 4WD
  • Front end vibration in 4WD
  • Grinding noise from front axle area
  • Differential fluid level low on inspection
  • Reduced braking performance on front wheels

How to Fix

For axle seal leaks: Replace the inner axle seals on the affected side (Mopar 68216218AA, $25-50 each) and inspect the axle shaft for wear at the seal surface. If the axle shaft is grooved, install a Speedi-Sleeve repair sleeve ($30). If brake contamination occurred, replace front brake pads and rotors ($300-500). For u-joint failure: Replace with Spicer Life Series (SPL55-3X) u-joints rated for 3500-class loads ($50-100 per joint, 2 per side). Total repair: $400-1,200 depending on extent.

What you need to fix it

Only diagnosis- and fitment-reviewed repair parts are linked here.

  • AAM 40201742 Ram 9.25 front axle tube seal

    Applicable 2003-2022 Dodge/Ram 2500/3500 4WD AAM 9.25 front axle; within this card, verify 2013-2022 axle tag and seal dimensions.

    C&M Gearworks
  • AAM 74081555A / Spicer 5-3212X front axle U-joint

    2010-2023 Ram 2500/3500 AAM 9.25 front axle using the 1555-series 74081555A/5-3212X joint; verify axle and dimensions.

    Drivetrain America

As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

Typical repair cost:$200 - $1,200

Research This Issue

Based on 1,650 owner reports

GoogleRedditYouTubeNHTSA
Community Reported
High Confidence1,650 owner reportsLast reported by owners Feb 2026Reviewed Feb 2026

On the 2010-2025 RAM 3500 6.7 Cummins, the intake grid heater relay fails, preventing the grid heater from warming intake air during cold starts. The grid heater draws significant current (up to 200 amps), and the relay contacts eventually burn and weld or fail open. Without the grid heater, cold-start performance degrades significantly in temperatures below 40°F — longer cranking, white smoke, rough idle, and potential no-start conditions in extreme cold.

Common Symptoms

  • Hard starting or extended cranking in cold weather
  • White smoke on cold start
  • Grid heater warning light not illuminating
  • Rough idle for several minutes after cold start
  • Check engine light with grid heater circuit codes

How to Fix

Replace the grid heater relay (Mopar 56055666AB or equivalent). The relay is located on the intake manifold or firewall area and is a straightforward replacement. Some owners upgrade to a heavy-duty aftermarket relay rated for higher amperage to extend lifespan. Also inspect the grid heater element itself for damage or corrosion while the relay is being replaced. Budget $80-$250 for parts and labor.

What you need to fix it

Only diagnosis- and fitment-reviewed repair parts are linked here.

  • Genuine Mopar 5187880AC grid-heater relay

    2006-2018 Dodge/Ram 5.9L/6.7L Cummins as listed; within this card use for confirmed 2010-2018 applications.

    Geno's Garage

As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

Owner tips & cautions

  • TipThe grid heater relay is cheap and easy to replace yourself. Keep a spare in the glovebox if you live in a cold climate — a $30 relay can save you from a no-start situation in winter.
  • TipWhen replacing the relay, inspect the connector terminals for heat damage or corrosion. Burned terminals will kill a new relay quickly — replace the pigtail connector if damaged.
Typical repair cost:$80 - $250

Research This Issue

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Community Reported
Medium Confidence

On the 2013-2025 RAM 3500, the factory 5th wheel and gooseneck towing prep wiring harness corrodes at the in-bed connector junction, particularly where it connects to the 7-pin and 4-pin trailer connectors under the bed. Water intrusion from rain, truck washes, and bed spray deteriorates the connector terminals and causes intermittent trailer light failures, brake controller communication issues, and auxiliary camera dropouts. The issue is worse on trucks used in snow belt regions due to road salt exposure.

Common Symptoms

  • Intermittent trailer running lights
  • Trailer brake controller shows no connection
  • Backup camera for trailer intermittently drops out
  • Trailer turn signals work only sometimes
  • Corrosion visible on in-bed towing connector

How to Fix

Inspect the under-bed wiring junction and connector terminals. Clean corroded terminals with electrical contact cleaner and a wire brush. Apply dielectric grease (Permatex 22058) to all connector terminals to prevent future corrosion. For severely corroded connections, splice in new Weatherpack or Deutsch sealed connectors. Seal the connector junction box with RTV silicone to prevent water intrusion. Budget $50-$300 depending on severity.

What you need to fix it

Only diagnosis- and fitment-reviewed repair parts are linked here.

  • Permatex 22058 dielectric tune-up grease, 3 oz

    Universal electrical-protection consumable, not a connector repair. Apply a thin film as directed after conductive contact surfaces and seals are restored.

    Advance Auto Parts

As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

Owner tips & cautions

  • TipApply dielectric grease to all trailer connector terminals during your annual towing prep. Two minutes of prevention saves hours of roadside troubleshooting with a loaded trailer.
  • TipSeal the in-bed connector junction box with Permatex Ultra Grey RTV. The factory seal degrades and lets water pool around the connections, especially after truck bed washes.
Typical repair cost:$50 - $300

Research This Issue

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Community Reported
Medium Confidence
Community reported
2,200 owners

On the 2013-2025 RAM 3500 6.7L Cummins, the RAM 3500 6.7L Cummins equipped with the integrated exhaust brake system experiences failures of the VGT (Variable Geometry Turbocharger) actuator and exhaust brake solenoid. The exhaust brake uses the VGT turbo vanes to create backpressure for engine braking while towing. The electronic actuator (Holset HE351VE/HE300VG) sticks or fails due to carbon buildup, causing loss of exhaust brake function, reduced turbo performance, limp mode, and DTC codes P2263 or P006A. TSB 14-001-21 addresses VGT actuator calibration. Actuator replacement costs $800-1,500; complete turbo replacement is $2,500-4,000.

This issue also affects: Chrysler 200, Chrysler 300, Chrysler Aspen

Common Symptoms

  • Exhaust brake not engaging or weak braking effect
  • Check engine light with turbo codes (P2263, P006A, P0299)
  • Reduced engine power / limp mode
  • Black smoke from exhaust under acceleration
  • Turbo whistle or surge at idle
  • Slow turbo spool-up / turbo lag
  • Exhaust brake light blinking

How to Fix

For sticking actuator: Remove and clean the VGT actuator and turbo vanes of carbon deposits. Actuator exercise procedure via wiTECH can help prevent sticking. Check TSB 14-001-21 for actuator calibration procedure. If the actuator motor is failed, replace the electronic actuator assembly ($800-1,500, Holset 5497296 or 5610723). If turbo vanes are severely carboned or damaged, complete turbo replacement is needed ($2,500-4,000). Regular highway driving helps keep vanes clean; trucks that idle excessively build up carbon faster.

Typical repair cost:$200 - $4,000

Research This Issue

Based on 2,200 owner reports

GoogleRedditYouTubeNHTSA
Community Reported
High Confidence2,200 owner reportsLast reported by owners Feb 2026Reviewed Feb 2026

On the 2010-2025 RAM 3500 6.7L Cummins, the exhaust manifold mounting studs on the 6.7L Cummins break due to repeated thermal expansion and contraction cycles. Broken studs allow the manifold to separate from the cylinder head, creating exhaust leaks that produce a ticking noise and reduce turbo efficiency. The center studs (#3 and #4 cylinders) fail most frequently. Attempting to remove broken studs often requires extracting them from the cylinder head, adding complexity to the repair.

This issue also affects: Chrysler 300, Chrysler Aspen

Common Symptoms

  • Ticking or hissing noise from the exhaust manifold area
  • Exhaust leak noise that changes with engine RPM
  • Soot or carbon deposits around manifold-to-head joint
  • Noise louder on cold start and fades slightly when warm
  • Slight power loss from exhaust leak affecting turbo

How to Fix

Remove broken studs using a left-hand drill bit and easy-out extractor set. If the stud breaks flush or below the head surface, a professional machine shop extraction may be needed. Replace all studs with upgraded ARP 247-4206 stud kit, which is stronger than OEM. Always replace the exhaust manifold gaskets during this repair. Budget $400-$1,200 depending on how many studs are broken and whether machine shop extraction is needed.

Owner tips & cautions

  • TipARP 247-4206 exhaust manifold stud kit is the definitive upgrade. Stronger than OEM and far less likely to break again. Worth the investment on any Cummins.
  • WarningSoak broken studs with PB Blaster for 24+ hours before attempting extraction. Rushing the extraction is how studs break off flush with the head, turning a $400 job into a $1,200 machine shop visit.
Typical repair cost:$400 - $1,200

Research This Issue

GoogleRedditYouTubeNHTSA
Community Reported
Medium Confidence

On the 2010-2025 RAM 3500, the front hub bearings (wheel bearing assemblies) in the RAM 3500 fail prematurely, particularly on trucks that carry heavy loads in the bed or tow heavy trailers. The factory hub bearings are adequate for unloaded driving but wear rapidly under sustained heavy GVWR/GCWR conditions. 4x4 models are more affected due to the additional stress of the front axle components. Bearing failure typically occurs between 60,000-100,000 miles on heavy-use trucks.

This issue also affects: Chrysler 300

Common Symptoms

  • Humming or droning noise that changes with vehicle speed
  • Noise increases when turning in one direction
  • ABS or traction control warning light
  • Play or looseness felt in the front wheel
  • Vibration in steering wheel at highway speeds

How to Fix

Replace the front hub bearing assembly (Timken HA590576 or Moog 515162 are highly rated). The hub bearing is a bolt-on unit on these trucks — 4 bolts from the back of the steering knuckle. Replace both sides if one has failed, as the other is likely not far behind. Use ABS-compatible hub assemblies. Budget $300-$700 per side for parts and labor.

What you need to fix it

Only diagnosis- and fitment-reviewed repair parts are linked here.

  • Timken HA590467 front hub and bearing

    Confirm VIN, drive, cab/chassis, build date, spline and ABS connector.

    AM Autoparts
  • Timken HA590628 front hub and bearing

    Confirm the exact notes and ABS lead before ordering.

    PartsGeek
  • Genuine Mopar 68292887AA front hub and bearing

    2019-2025 Ram 3500 6.4L/6.7L listed configurations; confirm VIN, axle ratio and current supersession, including 68292887AB where applicable.

    MoparPartsGiant

As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.

Owner tips & cautions

  • TipTimken HA590576 and Moog 515162 are the top choices for replacement. Avoid cheap imported hub bearings — they often fail within 20,000 miles on a 3500 that tows.
  • TipWhen one front hub bearing goes, replace both sides. If one failed at 80,000 miles, the other is likely at 85% wear and will fail within 10,000-15,000 miles.
Typical repair cost:$300 - $700

Research This Issue

GoogleRedditYouTubeNHTSA
Community Reported
Medium Confidence
NHTSA Recalls22 recalls

POWER TRAIN:AUTOMATIC TRANSMISSION:GEAR POSITION INDICATION (PRNDL)

Chrysler (FCA US, LLC) is recalling certain Ram 2500 and Ram 3500 vehicles equipped with a 3.5" cluster and column shifter. A software error may cause the gear selection display to be inaccurate. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 101, "Control and Displays."

Campaign #25V29700008/05/2025

ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL

Chrysler (FCA US, LLC) is recalling certain 2025-2026 Ram 1500 Pickup, Ram 2500 Pickup, Ram 3500 Pickup, Ram 3500 Cab Chassis, 4500 Ram Cab Chassis, and Ram 5500 Cab Chassis vehicles. A software error may cause the instrument panel cluster display to be blank. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard numbers 135, "Light Vehicle Brake Systems," 105, "Hydraulic and Electric Brake Systems," and 102, "Transmission shift lever sequence, starter interlock, and transmission braking effect."

Campaign #25V82600001/12/2025

AIR BAGS: AIR BAG/RESTRAINT CONTROL MODULE

Chrysler (FCA US, LLC) is recalling certain 2025 Ram 2500 Pickup, 3500 Pickup, 3500 Cab Chassis, 4500 Cab Chassis, and 5500 Cab Chassis trucks. A software error in the occupant restraint controller module may cause the driver's side air bag and/or seat belt pretensioner not to deploy in a crash and disable the electronic stability control (ESC) system. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard numbers 208, "Occupant Crash Protection" and 126, "Electronic Stability Control Systems."

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Frequently Asked Questions

What are the most common RAM 3500 problems?

According to Au7o's analysis of 6,650+ owner reports, the 2020 RAM 3500 has 7 documented issues. The most frequently reported are: Aisin AS69RC Transmission Overheating and Converter Shudder, AAM 11.5/11.8 Front Axle Seal and U-Joint Failure, 6.7L Cummins Exhaust Brake Actuator and VGT Turbo Issues. Of these, 2 are rated critical and should be addressed promptly.

Is the RAM 3500 reliable?

The 2020 RAM 3500 has 7 known issues documented across 6,650+ owner reports. 2 issues are rated critical: Aisin AS69RC Transmission Overheating and Converter Shudder and AAM 11.5/11.8 Front Axle Seal and U-Joint Failure. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.

How much does it cost to fix common RAM 3500 problems?

Repair costs for known RAM 3500 issues range from $50 to $4,000, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Aisin AS69RC Transmission Overheating and Converter Shudder, typically costs $300-$3,500 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.

What is the 2013-2025 RAM 3500 Aisin AS69RC Transmission Overheating and Converter Shudder?

The RAM 3500 equipped with the Aisin AS69RC 6-speed automatic transmission experiences torque converter shudder, overheating when towing, delayed shifts, and premature wear. The torque converter lockup clutch develops a shudder at light throttle and highway speeds. When towing he… Repairs typically run $300-$3,500. Severity: high.

What is the 2013-2025 RAM 3500 AAM 11.5/11.8 Front Axle Seal and U-Joint Failure?

The RAM 3500 4x4 with the AAM (American Axle Manufacturing) 9.25 front axle experiences premature front axle seal leaks and u-joint failures. Differential fluid leaks from the inner axle seals, contaminating the front brakes. The front axle u-joints (Dana Spicer 60) wear out prem… Repairs typically run $200-$1,200. Severity: high.

Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.

Data sourced from 6,650+ owner reports, NHTSA recalls, TSBs, and automotive forums.

Campaign #25V88200018/12/2025

ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL

Chrysler (FCA US, LLC) is recalling certain 2025-2026 Ram 1500 Pickup, Ram 2500 Pickup, Ram 3500 Pickup, Ram 3500 Cab Chassis, Ram 4500 Cab Chassis, and Ram 5500 Cab Chassis vehicles. A software error may cause the instrument panel display to fail. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standards numbers 102, "Transmission Shift Position Sequence," 105, "Hydraulic and Electric Brake Systems," 108, "Lamps, Reflective Devices, and Associated Equipment," 126, "Electronic Stability Control Systems for Light Vehicles," 135, "Light Vehicle Brake Systems," 138, "Tire Pressure Monitoring System," and/or 208, "Occupant Crash Protection."

Campaign #26V22500009/04/2026

EXTERIOR LIGHTING:BRAKE LIGHTS

Chrysler (FCA US, LLC) is recalling certain 2024-2026 Jeep Wagoneer S, 2025-2026 Ram 1500 Pickup, Ram 2500 Pickup, Ram 3500 Pickup, Ram 3500 Cab Chassis, Ram 4500 Cab Chassis, Ram 5500 Cab Chassis, and 2026 Jeep Cherokee vehicles. Due to an improperly designed trailer tow module, the trailer lights may fail to illuminate and the trailer brakes may fail.

Campaign #26V05900002/02/2026

+ 17 more recalls. Check all on NHTSA.gov

Enter your VIN at NHTSA.gov to check recalls specific to your vehicle.

What is the 2013-2025 RAM 3500 6.7L Cummins Exhaust Brake Actuator and VGT Turbo Issues?

The RAM 3500 6.7L Cummins equipped with the integrated exhaust brake system experiences failures of the VGT (Variable Geometry Turbocharger) actuator and exhaust brake solenoid. The exhaust brake uses the VGT turbo vanes to create backpressure for engine braking while towing. The… Repairs typically run $200-$4,000. Severity: medium.

What is the 2010-2025 RAM 3500 Exhaust Manifold Stud Failure (6.7L Cummins)?

The exhaust manifold mounting studs on the 6.7L Cummins break due to repeated thermal expansion and contraction cycles. Broken studs allow the manifold to separate from the cylinder head, creating exhaust leaks that produce a ticking noise and reduce turbo efficiency. The center… Repairs typically run $400-$1,200. Severity: medium.

What is the 2010-2025 RAM 3500 Grid Heater Relay Failure (6.7L Cummins)?

The intake grid heater relay fails, preventing the grid heater from warming intake air during cold starts. The grid heater draws significant current (up to 200 amps), and the relay contacts eventually burn and weld or fail open. Without the grid heater, cold-start performance deg… Repairs typically run $80-$250. Severity: medium.

What is the 2010-2025 RAM 3500 Front Hub Bearing Failure Under Heavy Load?

The front hub bearings (wheel bearing assemblies) in the RAM 3500 fail prematurely, particularly on trucks that carry heavy loads in the bed or tow heavy trailers. The factory hub bearings are adequate for unloaded driving but wear rapidly under sustained heavy GVWR/GCWR conditio… Repairs typically run $300-$700. Severity: medium.

What is the 2013-2025 RAM 3500 5th Wheel / Gooseneck Prep Wiring Corrosion?

The factory 5th wheel and gooseneck towing prep wiring harness corrodes at the in-bed connector junction, particularly where it connects to the 7-pin and 4-pin trailer connectors under the bed. Water intrusion from rain, truck washes, and bed spray deteriorates the connector term… Repairs typically run $50-$300. Severity: low.