Help.....
 

I put a 2.5AS on my truck the other day and now I have a weird noise coming from the front right of the truck. It sounds like a piece of metal grinding or hitting something. I thought I might need an alignment so today I had my new tires put on and an alignment done, but it is still doing it. I have had the truck at the mechanic all day and they don't know what it is. The weird thing is it only makes the noise when you hit the gas, and it won't make the noise in four wheel drive. When the truck is on the hoist and in drive it won't make the noise or when you spin the wheel with your hand it won't make the noise either. They replaced my tensioner pulley and belt and put some metal straps around a heat shield on my cat, but that didn't fix it. All of the bolts are tight that we took apart and torqued to spec. Any ideas or help would be greatly appreciated. Thanks. My truck is a 2004 F150 Supercrew FX4 with the 5.4.

Did you get the offset version of the spacer? The only thing I can think of is when you get the gas the rear of your truck squats, the front end comes up and your upper A-arm/Ball joint hits the coil spring. I believe this would be an extreme case as contact is not "normally" made until the tire leaves the ground....