Shocks
 

I have a xte pro. The shocks on one
Side of vehicle flop down or compress spring easy somewhat floppy. The other side u can here oil compress and decompress hydraulics slowly. When I run a 2s battery it runs fine. A 3s it sometimes kicks to one side aiming/darting another direction. This is grass yard play by the way. Was just curious if the shocks being blown out one side could cause this or if I should just blame terrain it's a Smaller 10th scale truck. It isn't jumped just tossed a few times when it wipes out so idk how the oil could leaked out

Power will always try and go to the tire with the least resistance when using differentials. To overcome this, and if you have sealed gear diffs, various thicknesses of diff fluids are used to tune the resistance of the internal diff gears.

if this is a RTR, then chances are the manufacturer didn't properly build the shocks, typically you need to apply grease on all rubber seals throughout the car (including the seals on the shock cartridges)... I would rebuild the shocks and apply a generous coat of grease on the rubber seals and that should do the trick to prevent leaks... oh and RTR actually means "Ready To Reassemble" :(

I'd say it's a combination of things causing truck to dance around.

If I recall, the Blackouts have sealed diffs. That's great! But I'm sure they don't come filled with anything other than grease. Filling the diffs with something like 30k ~ 50k diff fluid, and I think you will see a difference in power being put down.