What causes a SPN 4706 code?

SPN 4706 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 4706 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 4706 active.

How do I fix SPN 4706?

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 4706

Allison transmission code P4706

What it means

Output Shaft Speed Target Selection Error. This occurs when the TCM detects an implausible relationship between the engine speed, turbine speed, and output shaft speed sensor signals.