I bought a Rustler XL-5 couple weeks ago. I bought a Piranha Intellipeak Charger and GP3300 battery from Radio Shack, and a 4200 Dynamite pack. Both 6 cell. I am charging them both to peak and my run time stink. Some guys are telling me they are getting almost thirty minutes of run time and I am getting like ten on the 4200, and even less on the 3300. Should I discharge these batteries? I though discharging NIMH was bad to discharge? I am using 3 amps for charging....Any recs?

If the batts are new then they may need a few charges to wake up. But you should be getting better runtimes. have you changed the gearing at all? Also make sure your gear mesh isnt to tight that will cause batts to drain fast.

I changed to a 21 tooth pinion istead of 23. Can't say I noticed much different run times though....

if your charger has a discharge feature go ahead and discharge batts after peak charging. note discharge rate and time, to compare to rated mah