Tire Pressure

The placard on my 2016 Tacoma TRD Sport 4x4 says 29 lbs front and back. I noticed the other day the dash is reporting 35 and 36 lbs. I just brought the truck in for warranty repair for the BSM failure- I thought they are supposed to check other stuff while it's there, but no big deal.
My questions are:
1. Should I lower the pressure down to the recommended 29 lbs?
2. What is the downside of keeping the tires at 35lbs?
3. If I do lower them down to the recommended 29 lbs, do I simply have to press the tire pressure setting button on the dash? I think the manual says I have to drive it for 10 miles at 35 mph or higher first?

 

To high psi can cause the middle of your tire tread to wear faster than the shoulders.

Don't trust dealerships to do good work. My truck had a clutch job done at a dealer in Pennsylvania before i bought it. They left a bracket loose and a bolt halfway hanging out of the transmission.

 

I run 34psi (Cold) in my tires.