Ford Transit 2015–2019 — technical service bulletin
Bulletin TSB 21-2408 · NHTSA communication 10203655 · issued Nov 19, 2021
Technical service bulletin
communication type
Equipment
component
2015–2019
model years
5
vehicle entries
Official summary
Some 2015-2019 Transit vehicles equipped with a 3.7L engine and block heater may exhibit a repeat coolant leak from a deteriorated O-ring and/or intake manifold thermostat housing. This may be due to the block heater in the thermostat housing. To correct the condition, install a block heater service kit in the engine block.
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.