Incorrect Speedometer Reading

[djichee]

I have a 2004 GMC Sierra 1500. I have gone from stock wheels to 22" custom wheels and now my speedometer readings are not correct. How can I calibrate the speedometer to read correctly? Also is there anything else that needs to be done to prevent any problems that may occur with wheels this size? Thanks in advance for the input.

[03blackburb]

You will need a hand held tuner to corect the speedo. A couple of options are go to dealer and they will charge about $100 to reprogram or check with a local hight school that has a auto shop class. They can do it and probably will not charge you.