alright, i was at my hobby shop and i picked up some 50K diff lube, the reason was because the shop owner said that you will notice a better throttle response. Now before i picked it up i was running top gearing at 31/76 with the vxl setup. then i switched to 18/90 after i replaced the tranny gears. it ran better and i noticed better throttle response which was probably because of gearing. but now tonight i switched to 31/76 and it takes DAAAAYYYSSSSS to get to top speed and my exceleration is veeeeeeery slow!! is this normal....is 50 000 weight too much?