Tech - Awd - 900 miles so far - I took a trip to mountains this weekend and while returning back there was a steep slope in portions of freeway (6% to 8%). When I applied brakes on the slope to slow down from 70 mph to 60 mph , I felt vibrations in steering and front seats. At first I thought it was the abs kicking in ,but as far as I know, abs vibrations should be felt only in the brake pedal. I do not feel any vibration when braking on level ground, but I have not tried hard braking on level ground yet. I did call my dealers service department about it and they asked to complete 1000 miles and bring the car in for a check. I will post my updates here once they look at it.

 

Sounds like the rotors warp when heated. Check to see that the lug nuts are torqued evenly to spec or it could be a defective rotor.

 

Going to get both these things checked out over the weekend when I go to the dealer.

 

I don't know if anyone has mentioned this yet, but when going down a steep grade, you can push the D/S button to put the transmission into S mode and it will maintain the speed you were at when you pushed the button. This week while going down the Cuesta Grade in my area, every other vehicle was using their brakes while my RDX maintained 70-71 mph without any application of the brakes.

 

Lugnut torque is critical in avoiding "warped" rotors. Overheating the brakes will cause glazing of the pads and possibly rotors but warped rotors are usually the result of uneven or excessive lugnut torque or a quick change in temperature (e.g. running through a puddle of water when the brakes are hot).

 

Update: Dealer inspected and found both front rotors had excessive run out. So they resurfaced the rotors and it feels better now. I know brand new rotors should not need resurfacing but they mentioned they found it many new cars and even some the replacement rotors so they suggested resurfacing instead of replacement. I will monitor these for a while and if the issue still persists I will open a case with acura directly.