Lifted Ram 4x4

[Grant]

I have have been told by a local 4x4 shop that a 3" Rancho suspension lift is not enough to fit 35x12.50's on the truck. Why is this? In the past, ('94-'97) in all the 4x4 magazines, all the major manufacturers (Rancho, ProComp, Skyjacker) claimed that 35's will fit under the Ram with 3" of lift. Now, they say that 5" lift is needed. There are several trucks here in Ft.Worth with 3" lifts with 35's. Also, I was told that 15 inch wheels will not clear the brake calipers on '99-'00 trucks. Is this true? I really like 15x10's rather than 16.5x9.75's because the 16.5's dont have a bead in the wheel..... Sorry for the long message. Any help is greatly appreciated.