does anybody know the reason why my truck does this?
 

when im going less than 15mph, my truck will go straight down the path, but as soon as i hit the throttle, itll veer to either the left or right. ive asked this before, but maybe some others out there know the fix for this.
BUT besides that ok, even say i cant fix that problem, another funny thing it does is, so say it veers to the right, i would turn my wheel on my controller to the left a little bit, usually this would center the truck so that i can go straight, but no, my trucks then starts veering to the left!! why in the world??
please someone have the answer to my nightmare
just to let you guys know, ive put heavier diff oil and got true tracks, stiff springs but didnt solve this issue.

My best guess would be a sluggish servo. :yes:

You need a better servo, or a stronger servo saver spring!

is bad servo the cause for problems one or two? hmm..maybe ill try compressing the saver spring to that its stiffer and see if thatll help.
man , i spent lots and lots of hours trying to figure this out but now im totally stumped. like i dont even know what to replace even if i wanted to. dude ill even send $20 to the person that can solve my 2 probs. haha

Is it only when accelerating or while at a steady speed?
Does it do it on all types of surfaces?
It's an e-maxx is it? What tires?

Check for the ultra-obvious also, be sure you have no stripped hexdrives or missing drive pins.

It sounds to me like your steering servos are not syncing, which might be as simple as a faulty position sensor in one of them? Just a guess. I would remove one servo temporarily and see if the problem persists.

The 3905 rx has 2 outputs for steering servos, right?

If so, then try running one of each servo, with one horn or complete st. servo temporarily removed, but try the one connected servo in both of the rx steering outputs to rule out a bad rx/ rx connection.

its not really accelerating, but when accelerating at higher speeds. when i accelerate and stay under 15 mph...no problem but as soon as i wot or even half throttle, then itll start to veer to one side. yes it does this on all types of surfaces. its a emaxx with losi zombie maxx tires.
red shift thats funny how you said about trying one server and disconnecting it from the rx, cus my fren just offered me that advice like 2 hours before you said it. im going to try it out when i get a chance. i ruled out the obvious and the not obvious. i think i pretty much checked everything possible (that i know of) other than the servo issue, but i did check the inside of the servers to make sure theres no broken gears.
so far, it looks like everyone is saying its the servos fault.i really hope you guys are right. any other suggestions just so i have more options to look at?

this happened to me on my tc4...

mid to low speeds it would go fine..pull the trigger hard and it would veer off. I tried messing with my steering trim and everything, nothing was working.

a guy at the track come up to me and says "you need a new dogbone?, I got one if you need it" I was like "what?"

...He was talking about the cvd's/driveshafts.

I had popped a pin out of one of my front ones(broken it) and it would work at slow speeds but at high speeds it wouldn't spin as fast as the other...causing me to veer into the rails.
When I would pick the car up in the air, and pull the trigger, all four tires spun without issue. It wasn't until I started grabbing one wheel at a time that I found out the front one was busted. I could tell because the shaft kept spinning when I helt the wheel.....Frustrating as ****!

check to see if that might be it. if your'e running the stock sliders...one may be stripped

my truck has plastic driveshafts, its not cvds or metal dogbones. but ill try holding the tires to see if one still spins. so i just have my truck upside down, then hold one tire at a time, and the tire that im holding, the driveshaft is not suppose to spin right, only the remaining 3? will this twist my driveshafts though?

Well the best way is to take off all the wheels and give it a visual inspection. But if removing 4 wheel nuts is too much, then the way to do it is have it upside down on your lap and gently grasp both fronts, then both rears while someone else bumps the throttle slightly with the transmitter. This way you'll be certain all 4 are getting power.

If in all this you've never checked all the drive pins - its time.

While its upside down, take your 2mm driver and find the small half moon cutouts in the skids. There are 2 on each end, one on each side. This is the hole you tighten the drive axle drive pins through. Get a light and rotate wheel until you have the socket end of the drive pin lined up with the hole, make sure each one is tight.

I don't use these plastic 3.3 cvds for center drives, but now that you see what's involved, make sure you check them as well. I check my driveline prob every 6 or 8 runs, I might over do it, but its peace of mind.

so when i hold the two front tires and give it gas, what is it suppose to do? are the driveshafts suppose to still spin or be stuck? am i basically just trying to feel both tires trying to turn?

and i just checked all 4 drive pins...all were snug. thats another thing i didnt inspect (i thought i looked everywhere possible almost at least which is why im aksin you guys)

yeah.

I guess my main point was to see if all 4 tires were giving the same about of torque under load. I suggest putting the truck up on something with the wheels suspended(free to spin). While the trigger is being pulled (lightly...if you are by yourself you can try to turn up your throttle on your transmitter till the wheels just start to spin)anyway--if one wheel is easier to stop than the other three, then that is the wheel that is spinning slower and causing you to veer off under throttle.

by the way..don't hold the wheels so tight that you break anything...i merely meant for you to find a part that may already be broken

Is it the amount of throttle you apply, or the speed? If it's a speed-related issue, check your toe and camber settings. At high speeds, a little bit off makes it act funny. I just had to return my Slash suspension for this very reason.