Perfect rail balance:"letitslide"
Perfect manual balance:"keepitsteady"
Moon gravity:"getitup"

Well when you get 1st place on the MTX demo, the code it gives you is holeshot, the get the code and go to mtxmototrax.com and put the code in, then it should give you the code for a cheat for Underground. Hope this helps.

In N.J.(New Jersey) theres a fence right by the drainage ditch.put in Moon gravity(getitup)and jump up and up and up until your stuck than release up which
You need to be holding in order to do this.as soon as you release it press X.
Than at the top of your jump press up and repeat unti you go forward and begin
To fall. Let him fall and now you should be able to run around out of bounds.
Enjoi! :) ;) :0 ;0 (.)(.) :+) :-) >) XD X) X( X-O B) BD :~)

Okay I thought this was pretty cool...First enter the moon gravity cheat (getitup) and then go anywere of choice and turn it on (pause,options,cheats). Next go up to any building- preferibly a tall one- and jump on the wall. Continue to press X and eventually you will reach the top.... Try it....

For perfect manual, you can type keepitsteady at the cheats menu
For perfect rail, you can type letitslide at the cheats menu
For perfect skitch, you can type rearrrirer at the cheats menu
For moon gravity, you can type getitup at the cheats menu

For this cheat you need to have completed the game and have the cheats. Put on the cheat "cool specials". Then get enough air and do a special AIR move( e.g. McTwist) and half way through the move pause the game and take off "cool specials". When you land you should be in slo-mo. To get out of slo-mo all you have to do is bail.

First go to Slam City Jam and go to the seats. Now go to seat section P, now jump on top of the stairs to the high seats and BOOM! you now go to the crowd seats. Warning, if you exit out of the crowd seatsand go back you will be out of bounds.

Ok I erik90000 have descovered the coolest glitch ever! Don't copy this because I've never seen it on any site before ok enough with all that here it is:

Go to new jersey then go to the end of the bridge there as soon as you step of the bridge walk left along the river until you hit a forcefield or can't walk any further now holld up or whatever button makes you walk into the invisible wall now start pressing x keep pressing it and soon you will start jumping up the invisible wall keep going remember to press into the wall while you do this soon you will go forward a little when you jump if you do stop holding or pressing everything you should come down alittle and stand in mid air! Go right and you will walk a little or go forward and you will fall off the wall andland on the other side of the invisible wall! Now tou can walk through the building wall there you can't walk to far or theres another wall that you can't jump over but if your playing like hide and seek like I heard someone talking about step through the building wall and theyll never see you!

Ps. You can jump over any other invisible wall or building including the one behind the burnt building in new jersey to get to the other side of the fence

The cheat you get when you beat the MTX demo is HOLESHOT. You have to enter it at MTXmototrax.com.

Hey people! Use these names under create-a-skater name to unlock alot of new skaters! Here they are: 1337, akira2s, alan flores, alex garcia, andy marchel, arrr, bailey, big tex, chauwa steel, chris rausch, chrisp, crom, daddy mac, dan nelson, dave stohl, ddt, deadendroad, frogham, geiger, greenie, grjost, guilt ladle, hammer, henry ji, jason uyeda, jeremy andesen, joel jewett, johnny ow, leedsleedsleeds, marcos xk8r, mike ward, moreuberthaned, m'yak, noly, nsjeff, pooper, skillzombie, stacey d, tao zheng, the kraken, the swink, thedoc, todd wahoske, topbloke, tsuenami!, woodchuck, y2kj, yawgurt, and zig. it doesn't matter what kind of letters their in, either lower case or capital.

If you were playing t.h.u.g. with your friend(s) you could play 'HIDE AND SEEK'.. hear are some great spots that you will never be found in...
Tampa: go down past the bank to the wet bevers boat and hide behind the ramp beside the hut...

Hawaii: go behind the littel market and find the EVIL TIKIE.jump into the mouth and you end up in another dimention.(dosent work first time).

Vancover: put on moon gravity go to the out side of the hotel and keep yer finger on x until you go through the roof youll land on a platform then walk down you should go through the floor and then put on kid mode.(if you have it).

Slam City Jam: last but not least....Agen put on moon gravity then go up to any section.beside the grind rail there is a set of stars. go down 2 or 3 stairs and jump at them then keep pushig x till you land on them.then you can run around the crowd.......

In moscow turn the first corner and then get onto the orange building. Get onto the side and then grind and then ollie and then you will smash through the window.

Jump off your board, walk up to the higher level and then there it is!

At the create a skater menu type these as your name:
crom,
Noly,
POOPER
THEDOC.

if you beat the story mode once next time, if you play as the same charecter

when eric offers 'once around winner gets the tape' you hit him and take the tape without having to do the goal

'have some a that

i don't know if it work every time but it worked with me

Perfect rail Balance: Type in 'letitslide' at the cheat codes screen.

Perfect manual balance: Type in 'keepitsteady' at the cheat codes screen.

Moon physics: Type in 'getitup' at the cheat codes screen.

To get perfect manual balance enter "dontfall" as a cheat and get high scores,if you didn't know "space walk is left right square."

Enter all of these names how they are at the create a skater options.

Skillzombie
leedsleedsleeds
TOPBLOKE
sik
deadendroad
The Kraken
Hammer
WOODCHUCK
Y2KJ

The way to climb a building is first you must enable moon-gravity.

If you do not have the cheat in, go to the the main options, the go to cheat codes, then enter in "getitup" after you have done this select a level and the go to a building and press "x". Consantly or hold it and you should be able to climb a building.

at the cheat menu type LETITSLIDE