Truck Repair: A/C, dodge ram 1500, freon leak detectors

Question
Do you know of any common freon leaks found in ac units on 1998 Dodge Ram 1500?  I know this isn't really your area but maybe you can help.  Do you know of ways I can find the leak?  Thank you for your help and time.

Answer
Well being a 1998 model,it has 134A freon in it.They make freon leak detectors,but they are pricey for the weekend shade tree mechs to buy for once or twice a year use.Check local parts house for one.No I dont know of any known leaks on the A/C system.