Allison H 40 EP Transmission (ALLISON) - Transmission System Fault (2020)
Check Your Product
According to the National Highway Traffic Safety Administration (NHTSA)
Product
ALLISON H 40 EP TRANSMISSION
Brand
ALLISON
Lot Codes / Batch Numbers
Not specified in NHTSA notice. Check official source for details.
Allison Transmission, Inc. is recalling certain ALLISON H 40 EP TRANSMISSION equipment due to power train:automatic transmission issues. A loss of drive can disable the vehicle unexpectedly, increasing the risk of a crash..
Summary derived from NHTSA notice
Reason for Recall
As stated by NHTSA
Allison Transmission, Inc. (ATI) is recalling certain Drive Units: H 50 EP (part numbers 29540673 and 29540900), H 40 EP (part numbers 29540697 and 29549708), H 50 EP Cert (part numbers 29556925 and 29556926), and H 40 EP Cert Drive (part numbers 29557038 and 29557036). The pressure switches on these Drive Units may fail, possibly resulting in a loss of drive.
Reported concern (NHTSA)
A loss of drive can disable the vehicle unexpectedly, increasing the risk of a crash.
Recommended Action
Per NHTSA guidance
ATI will notify the manufacturers that purchased the affected equipment, and ATI dealers will replace the C1 and C2 pressure switches in the affected drive units free of charge. The recall began August 10, 2020. Owners may contact ATI customer service at 1-317-242-5000.
Verify this information on the official source
For complete details and official instructions, check the National Highway Traffic Safety Administration (NHTSA) directly.
View official NHTSA recall noticePage updated: Jan 10, 2026