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RecallGazette

Vehicle problems, recalls & safety intelligence

Ford Mustang 2020–2021technical service bulletin

Bulletin TSB 21-2330 · NHTSA communication 10201637 · issued Sep 24, 2021

Technical service bulletin
communication type
Power Train
component
2020–2021
model years
2
vehicle entries

Official summary

Some 2020 Mustang GT350 - 2020-2021 Mustang Mach 1/Shelby GT500 vehicles may exhibit a rear differential fluid leak at the differential cooler line fittings. This may be due to a seal within the fittings. To correct the condition, follow the service procedure to replace both rear differential cooler line fittings.

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.