new brakes in front, squeal only in reverse

Just threw a new set of pads in the front of my 2008 CX9 GT. Rotors were fine, so no need to have them turned. When I put the car in reverse from a stop there is a high pitched squeal. Hardly at all when I go forward. (boom06)

Semi-metallic or ceramic pads? and not turning them may also have something to do with it. Did you retain the factory chrome like shims or discard them and just use the shims with the pad, double or single shim?

What I'm getting at is your post is not that specific, and it could be alot of things. Cheap semi-metallic pads squeal, its just a fact of life, but not sure what pads you used. Pads tend to squeak when replaced on existing rotors sometimes. Shims also make a large difference in a good or bad way. My factory shims were causing a loud pop every time I would accelerate off the line, so I ditched them when I put new pads on. My ceramic pads only have a built in shim, adhered to the back of the pad...and that is all I am using, no other shim. Also, if your brake hardware kit is not re-installed correctly, it will not pull the pads away from the rotor when you take your foot off the brake.

Give us more info to help with the issue.

used the built in shim. If it does not get any better, I'll just turn the rotors.

No need to turn perfectly good rotors at each pad replacement. Waste of time and it is not needed. What you need to do is do a break-in of the new pads to the rotors.
Several stops from 60 down to 10mph, using a firm brake to the point of almost but not engaging the ABS, then drive without braking for 1 minute and let the rotors and pads cool, then do it again! Try to do it at least 3-5 times. This will break them in properly. The squeal in reverse is typical due to the fact that the rotor and pad are moving forward 99% of the time, so when you go into reverse they make the noise as they are hitting deposits going in the other direction. So you need to remove these deposits with the new pads in the method above to reduce or get rid of that noise.

thats the way I drive normally, so it should not be an issue!(boom06)