Land Rover Defender 2023 — technical service bulletin
Bulletin D011 Defender 17JUL26 · NHTSA communication 11035856 · issued Jul 17, 2026
Technical service bulletin
communication type
Engine
component
2023
model years
1
vehicle entries
Official summary
Coolant Bypass Hose Leak
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.