What causes a SPN 4607 code?

SPN 4607 can be triggered by several issues — see the verified probable causes and step-by-step diagnostics shared by mechanics and owners on OBDIY.

Can I drive with a SPN 4607 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 4607 active.

How do I fix SPN 4607?

Follow the step-by-step diagnostic on this page, then read the verified fixes contributed by other Heavy Truck owners — the answer marked "Verified Cause" worked for the original poster.

OBDIY

J1939 SPN

SPN 4607

Allison transmission code P4607

What it means

Transmission Output Shaft Speed Signal - Low Voltage or No Signal. This indicates a mismatch between engine speed/input speed and the reported output speed of the transmission.