Just got my Genesis all back together after Ripmax replaced both front and rear diffs and all spur gears under warranty (there is hope for UK owners at last). I took it out for a bash yesterday and at certain speeds the whole car was shaking/vibrating quite badly so much so that the car was almost uncontrollable. At first i thought it was as it was changing into second but it seems to do it all the time. If i lift the car off the ground and give it a little gas it really does shake bad. What have i done wrong? the diffs came back ready assembled and marked front and rear i followed the instrutions to the letter on reassembly. The only thing that is different from before is that i have removed the center lock diff and put the supplied gears in. Also occasionally the genesis would lose drive to all wheels as if it was in neutral but if selected reverse the forward the problem went away but i'm thinking the shaking is causing the problem. Any ideas as what to check before i do a complete strip down again?

Brakes dragging can cause a nasty shake of the entire truck while on power, and damaged wheels and tires. If it were a drive train issue, i'd think it would break almost immediately.

You say that you are loosing power to the wheels, check the grub screws front and rear. I had big vibrations on mine but it turned out to be a bad foam at the right front wheel. So check your tires and rims, if the tires has been riped of from the wheel you may have destroyed the foam.

Brakes now theres something i overlooked will check that in the morning as they were all off too.

jadda the grub screws are fine (been there done that ) its like the truck has a neutral or the clutch disengages for a few seconds while on the gas.

Got around to looking at the Genesis today and found the problem, the tyre foams have broken up and were rather wet still. Do i have to get foams specially for the Genesis or are there others that might be easier to get. Also are there any different wheels that will fit that i can get, seems like a spare set is necessary.

Is it feasible to run without foam as the tyres a low profile???

You need to buy GS035 and there you will have the foam with the tires too

Got some foam cut locally for £2 slightly firmer than original seems to work well, saves buying tyres when mine are hardly worn.