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Service bulletins for the 2020 Ram 1500

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

1228 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

By topic

Only bulletins with component: Transmission and driveline are shown. Show all

Bulletins, newest first
21-015-202020-05-26. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM. Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may experience the following:Bump/clunk felt during 1-2 or 2-3 upshifts. Delay/hesitation during a 3-2 shift. Bump or shutter felt during engine start/stop (ESS) situation.
18-020-202020-05-26. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); ELECTRICAL SYSTEM. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customer may experience one or more of the following:Hesitation upon Engine Stop Start (ESS) autostart. Hesitation upon light acceleration below 20 MPH. Hesitation when accelerating while warming up, with coolant temperature below 60 ºC (140 ºF).
08-033-202020-05-18. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:PARK/NEUTRAL START INTERLOCK SWITCH. Intermittent No Crank No Start This bulletin involves inspecting the ground wire to engine block fastener and replacingif necessary. The customer may comment on the following:A no start and/or intermittent no start condition.
21-015-202020-05-18. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may experience the following:Bump/clunk felt during 1-2 or 2-3 upshifts. Delay/hesitation during a 3-2 shift. Bump or shutter felt during engine start/stop (ESS) situation.
08-028-202020-05-18. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). Flash: Hybrid Control Processor (HCP) Updates This bulletin involves updating the HCP with the latest available software. Customers may experience the following:Bump or shutter felt during engine start/stop (ESS) situation. The following enhancement is also included in this software update:Improvements to engine start stop quality to eliminate bumps or shutter. Improvements to motor rotor temperature model for robustness.
18-020-202020-05-18. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM:SOFTWARE; POWER TRAIN. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customer may experience one or more of the following:Hesitation upon Engine Stop Start (ESS) autostart. Hesitation upon light acceleration below 20 MPH. Hesitation when accelerating while warming up, with coolant temperature below 60 ºC (140 ºF).
21-015-202020-04-27. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may experience the following:Bump/clunk felt during 1-2 or 2-3 upshifts. Delay/hesitation during a 3-2 shift. Bump or shutter felt during engine start/stop (ESS) situation.
18-020-202020-04-27. Service bulletin. POWER TRAIN; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customer may experience one or more of the following:Hesitation upon Engine Stop Start (ESS) autostart. Hesitation upon light acceleration below 20 MPH. Hesitation when accelerating while warming up, with coolant temperature below 60 ºC (140 ºF).
18-011-202020-04-06. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; POWER TRAIN. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience the following:Extended or longer than usual engine crank time.This conditions usually happens after a cold engine start and the vehicle is turned off and turned on within 3-5 minutes this will result in an extended or longer crank than usual before the vehicle restarts.
21-007-202020-04-06. Service bulletin. POWER TRAIN. Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic trouble Codes (DTCs) have been set:P0731-00 - Gear 1 Shift Incorrect Ratio. P0733-00 - Gear 3 Shift Incorrect Ratio (while operating in 4-Lo range). P0734-00 - Gear 4 Shift Incorrect Ratio. The customer may describe the following:Bump/clunk felt during 1-2, 2-3, 4-5 or 5-6 upshifts. The following enhancement is also included in this software update:Improvements in prematurely setting the following DTCs: P0731, P0733, P0734. Improved 1-2, 2-3, 4-5 or 5-6 upshifts to eliminate bump/clunk felt during these upshifts.
18-010-202020-04-06. Service bulletin. POWER TRAIN. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. The customer may comment on one or more of the following:Bump sensation during a coast down with light acceleration. Abnormal vibration when accelerating lightly during stop and go driving conditions.
21-008-202020-04-06. Service bulletin. POWER TRAIN. Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic trouble Codes (DTCs) have been set:P0731-00 - Gear 1 Shift Incorrect Ratio. P0733-00 - Gear 3 Shift Incorrect Ratio (while operating in 4-Lo range). P0734-00 - Gear 4 Shift Incorrect Ratio. The customer may describe the following:Bump/clunk felt during 1-2, 2-3, 4-5 or 5-6 upshifts. The following enhancement is also included in this software update:Improvements in prematurely setting the following DTCs: P0731, P0733, P0734. Improved 1-2, 2-3, 4-5 or 5-6 upshifts to eliminate bump/clunk felt during these upshifts.
21-042-192019-12-16. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Customers may experience the following:Harsh 3-2 downshift. Harsh 1-2 and 2-3 upshifts when cold. 4-5 shift clunk.
90041502019-12-02. Service bulletin. FUEL SYSTEM, GASOLINE; POWER TRAIN. SEAL, Input If looking to replace stubshaft due to ATX fluid leaking, do not replace PTU seals. None of the seals from the PTU side will need to be replaced whenever the ATX stubshaft is replaced, even though V-seal (68408748A$) is in direct contact with the stubshaft, it will not avoid grease/oil leakage from transmission side. PTU V-seals are intended to act as a dust cover for stubshaft - PTU input shaft spline interface. PTU Input shaft seal (68408749A$) is intended to hold PTU oil and debris ingress; it should be replaced only if the fluid leakage is confirmed to be PTU oil and not ATX trans. fluid.
553092019-07-15. Service bulletin. EQUIPMENT; POWER TRAIN. Power Transfer Unit
545832019-07-15. Service bulletin. POWER TRAIN. Transmission ? With Torque Converter

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.