ORIGINAL: 7M

My Volcano SV, which has about the power of two SH .18's, has some really bad traction issues. It cannot go in a straight line without me going half throttle and driving like a grandpa. The problem is, when I full apply throttle, the back end would spin faster than a drifter on ice and one wheel would turn into a balloon. And turning it cannot be any worse. It would as usual, spin out sending me into a spin of holy G-horses. I have no idea what weight the diff fluids the Volcano came with factory. Now i'm thinking what if I change the Rear diff fluid to a thicker kind, as well as the front for better cornering. Ive searched, but i've only found info on 1/8 trucks or truggy's with the center diff. And BTW, I don;t spend much time on loose surfaces, she's a street queen.