Spark Plug Adapter – M-Series

These adapters are made by MWM off of an original military version. A far better quality product than other non military versions on the market. These provide the waterproof connection for the spark plug and will connect to the waterproof plug wires. They can be used on the M38, M38A1, M37 and M151.  Will NOT work on the M715. May also fit other M-Series trucks such as the Reo and GMC 2.5 ton trucks.
Spark plugs can be purchased at any auto parts store for these adapters for around 3-5 ea. Autolite and AC brands are recommended.  MWM also stocks the correct plugs for your application.