Code result
P279A
Transfer Case Gear High Incorrect Ratio
High severity
What it means
When the transfer case is in High range the measured input/output speed ratio does not match the expected value. Worn chain or planetary set.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Stretched transfer case chain
highOne of the most commonly reported causes for this code — check this first.
Worn planetary gear set
mediumA plausible cause — test and verify before replacing parts.
Related help
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