Vehicle speed sesor

[tmf6902]

I got a new radio in my truck and it hooks into the VSS. The radio has a speedo that runs off the vss....problem is the speedo that is on the radio reads differently than my real speedo....they're about 4-5 mph off......which do you think off....my cluster speedo, or the radio speedo that reads the pulses from the VSS.

[budhayes3]

I'm thinkin radio speedo.