buy the biggest MAH 5cell hump pack you can buy for your truck and at the same time, purchase a new onn off switch. unplug the current battery pack from your stock on/off switch. now remove your on off switch. install your new on/off switch, and plug it into the reciever. once your new batter is charged, plut it into the on/off switch.
i suggest you go to
www.promatchracing.com , and order a 5cell hump pack from them. the price will be really good, and they use only quality cells.
i got a 4200 Mah SubC 5cell Hump pack with a standard plug and Tamiya plug for my Baja for 35.00 SHIPPPED!!!> first charge went to 4647Mah. i expect about 10hrs use before needing recharged. will find out this weekend.
Timmahh