— Ram aisin transmission snap ring failures caused truck owners to complain to the point safety regulators opened an investigation into K1 snap ring failures in 2022 Ram 3500, 4500 and 5500 trucks.
The National Highway Traffic Safety Administration has received at least 82 complaints about the Ram trucks due to aisin transmission snap ring failures.
NHTSA says 16 complaints allege the Ram trucks completely stopped moving while driving above 25 mph, and the trucks could not be used again until they were repaired.
Because they are Ram 3500, 4500 and 5500 vehicles, they can be up-fit as an ambulance and other emergency response vehicle or may be heavily loaded when used for towing.
This is a serious matter for an emergency vehicle when the Ram aisin transmission snap ring becomes dislodged and 1st, 2nd, 3rd and 4th gears completely fail in an emergency.
(The photo above shows the underside view of a K1 snap ring correctly seated)
Ram Aisin Transmission Snap Ring TSB 21-002-23
NHTSA contacted FCA and learned about technical service bulletin (TSB) 21-002-23 which applies to Ram trucks equipped with 6-speed automatic aisin AS69RC HD transmissions or 6-speed automatic aisin AS66RCHD transmissions.
"K1 Clutch Snap Ring Repair: This bulletin involves replacing the K1 clutch drum snap ring and possibly the K1 input shaft drum sub-assembly." — TSB 21-002-23
The bulletin says Ram customers may see warning lights, and dealerships may find diagnostic trouble code "P0731-00 - Gear 1 Shift Incorrect Ratio."
A Ram driver may also complain the transmission will not shift into or out of 1st through 4th gears. However, 5th and REVERSE gears are still available.
CarComplaints.com will update our website with results of the Ram aisin transmission snap ring failure investigation which currently includes more than 188,000 trucks.
