I have a 2007 Prowler also and it started the noise at about 200 miles. I took it to the dealer to get it fixed. He replaced the entire braking system trying to diagnos this problem. He finally called the manufacturer and they supposedly told him they knew of the problem and would be upgrading. It has been over a year and the dealer hasn't heard any news. Unfortunatly the noise has only gotten worse and sounds like it is goin to blow something up every time I step on the brake. I questioned another dealer about the problem and he said because the brake is on the driveline the noise is coming from the gear slack in the transmission. To repair it you have to tear the trany apart. I don't know what to do about it since I definatly won't get my money back out of it if I tried to sell it.
A few other problems I've had are; trany shift linkage is constantly needing adjusted, hard to start, emergency brake is hard to disengage and won't even hold on a slight incline (for instance when loading on a trailer it rolls off faster than I can get it strapped on), about a week after putting the bed bars on the bed rail the rail cracked at all four corners and I barely tightened them enough to get a full nut on the bolt, the floor pan is starting to rip out of the screws thet hold it on, and to top it all off it is very hard to steer.
Needless to say I'm not too happy about my expensive purchase. If they have this many problems with less than 600 miles then they are not as tough as advertised. I use mine on the farm everyday just to change water and carry a toolbox, it's pretty bad if they can't handle that.
If any body has any suggestions please reply.