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P0218RAMRAM 3500 HubAll RAM P0218Critical Severity

P0218 on RAM 3500

Transmission Fluid Overtemperature Condition

Factory diagnostic protocol and troubleshooting wire for fault code P0218 specifically for the RAM 3500 (2020–2026, 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel)).

Verified OEM Telemetry & Field Repair Tree
RAM 35002020–2026
RAM 3500
Truck6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
3500 SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Not Recommended
Critical urgency level
Est. Repair Cost
$180 - $2,500 (DIY: $60 - $200)
Parts & Labor DIY
Check P0218 On Another RAM Model:
Diagnose P0218 on Specific 3500 Model Year:

1. Symptoms of P0218 on RAM 3500

When the Engine Control Module (ECM/PCM) on your RAM 3500 (6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel)) logs fault code P0218, drivers commonly observe:

Transmission Temperature Warning light or Check Engine Light on RAM 3500 (6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel))
Burnt transmission fluid smell on RAM 3500 (6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel))
Transmission slipping, delayed gear engagement, or harsh shifting on RAM 3500 (6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel))
Vehicle entering Limp Mode / stuck in 2nd or 3rd gear on RAM 3500 (6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel))
RAM 3500 OBD-II Port Location
The 16-pin diagnostic connector is located Driver lower kick panel near emergency brake assembly. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on RAM 3500

Historical warranty claims and technical repair bulletins for RAM 3500 point to the following failure distribution:

55%
Severe towing or hauling exceeding vehicle GCWR rating (RAM OEM Part)
25%
Low or burnt transmission fluid (RAM OEM Part)
12%
Clogged transmission auxiliary cooler or restricted lines (RAM OEM Part)
8%
Faulty transmission cooling thermostat or auxiliary fan (RAM OEM Part)
8%
Failing torque converter clutch generating extreme frictional heat (RAM OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for RAM 3500.

3. Step-by-Step DIY Repair Guide for RAM 3500

01
Pull Over and Cool Down

Safely park, leave engine idling in Park for 5 minutes to let transmission cooler lower fluid temperature. on the RAM 3500 equipped with 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel).

Required Tool: None
02
Check Transmission Fluid Level & Condition

Check dipstick with engine at warm idle. If fluid is dark brown/black or smells burnt, it must be drained and replaced. on the RAM 3500 equipped with 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel).

Required Tool: Clean Rag
03
Inspect Transmission Cooler for Blockage

Check front auxiliary transmission cooler for mud, bugs, or bent fins restricting airflow. on the RAM 3500 equipped with 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel).

Required Tool: Flashlight, Fin Comb
04
Perform Transmission Fluid & Filter Service

Drop transmission pan, replace internal filter, clean magnet, install new pan gasket, and refill with OEM synthetic transmission fluid. on the RAM 3500 equipped with 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel).

Required Tool: Pan Catch, Socket Set, OEM Fluid & Filter Kit
05
Clear Trouble Codes & Monitor Live TFT PID

Clear DTCs and monitor Transmission Fluid Temperature PID on scanner (normal operating range: 175°F–200°F). on the RAM 3500 equipped with 6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel).

Required Tool: OBD-II Scanner with Transmission Telemetry
Recommended Parts & Testing Tools

Equipment for Diagnosing RAM 3500 (P0218)

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Direct-Fit Replacement Part

RAM 3500 OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for RAM 3500.

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Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

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Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for RAM 3500Verified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on RAM 3500

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the RAM 3500:

4. RAM 3500 P0218 FAQs

What causes code P0218 to trigger on a RAM 3500?

On the RAM 3500 (6.7L High-Output Cummins Turbo-Diesel (420HP / 1,075 lb-ft torque / Dual Rear Wheel)), P0218 is most frequently caused by Severe towing or hauling exceeding vehicle GCWR rating or Low or burnt transmission fluid.

Where is the OBD-II port located on my RAM 3500?

On the RAM 3500, the 16-pin DLC diagnostic connector is located Driver lower kick panel near emergency brake assembly. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my RAM 3500 with code P0218?

No. Pull over and allow transmission to cool immediately. Overheating transmission fluid (>260°F) burns clutches and destroys seals. Given that P0218 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.