Chevy Tahoe speedometer and odometer

I purchased a 2005 Chevy Tahoe in 2009. My rpm gauge has not worked for 8 months, and the speedometer runs 2-40mph faster than actual speed. Does the odometer get it's readings from the speedometer. If it does, that would explain the high mileage readings on the odometer so that it is now just past warranty. How convenient. Also the lights on my steering wheel controls do not work anymore and the same with some of the radio controls. Dealer said there was a recall on the instrument cluster up to 80,000 miles. I am now at 96,000 miles.