I've used 7,000 in the front & 5,000 in the rears of my GorillaMaxx and FLM emaxx builds and it been a great combination so far. Whatever you do you will want heavier oil in the front then in the rears. As the trans area I’ve always used just synthetic grease, the new thing out at this moment is Gorilla Snawt
http://www.rc-monster.com/forum/showthread.php?t=12132
Hope that helps..