donkey punch

hey guys, my evo starts to shake a little bit around 60-75mph on the freeway (4th and 5th gear). its a brand new IX with only 1800 miles on the clock. my tire pressure is around 35-38 psi in all four tires. you could definetly feel it while holding the steering wheel at these speeds. i thought i was just being paranoid but it didnt feel this shakey about a week ago. any thoughts guys....im thinking it could be the alignment but i dont know. thanks

EvoTio

iTrader: (10)

It could be your alignment, but probably your wheels are out of balance. Definitely take it back to the dealership and have them take a look at your car.

epearson

+1 for wheel balancing

AllYouCanTiff

iTrader: (4)

balance your wheels!!

binarysleep

If you're impatient, rotate your tires (switching front to the rear) to confirm a bad wheel balance.

If you have any doubts about your dealers skills or integrity, then do not take it back to them as they will probably charge for a new balance. If you’re going to pay for a new balance, you might as well go to a performance oriented shop that will do a road force balance (horizontal & vertical) and will take care not to mark your rims.

Should they warranty it, yea, but $10-15 a wheel is well worth the out-of-pocket cost when it comes to properly mounted and balanced wheels!

fusionchicken

iTrader: (1)

balance your wheels. do an alignment. at those speeds if u're on an angled on/off ramp does ur steering wheel feel hesitant/resistant to move?

if it shakes under braking, check your brake pads and rotors.

i've had a similar issue when under braking, and it turned out my front right passenger brake pad had a big *** rock stuck inside.....****.

mathgeek

One more thing. To get the best performance your tire pressure needs to change. Your fronts should be 3 lbs higher than your rears. The recommendation is 32 front/29 rear. You can go two more for a little better fuel economy (34 front/31 rear) but there should be a three pound discrepency at all times.

donkey punch

thanks guys. my car is at the shop getting the wheels balanced w/ wheel alignment as we speak. hopefully this solves the issue when i get it it back. wow, i diint even know you had to have some sort of a PSI difference between the front and rear tire pressures...thanks yall. ill let you guys know how it comes out

os2

iTrader: (8)

Mine has been doing exactly the same thing at 60...75 mph for three years already. It does it on both stock Yoko's and Pirelli nero all-seasons. Shaking kinda goes away after 15-20 minutes (once flat spots on the tires are gone) while driving on a really smooth surface. I really hate driving between 60 and 75 , steering gets light and shaky but once I hit 80 everything is back to normal again. I looks like _a_lot_ of people complained on the same thing. Balancing, alignment and tire rotation did not fix this for me. I'm starting to think that there is some "resonance" in the suspension that takes place.
Wonder if anybody with aftermarket spings/coilovers with different spring rates or swaybars can chime in...Something's telling me that coilovers will take care of this

AllYouCanTiff

iTrader: (4)

dude, one thing tho, my wheels get outta balance soooo often. i have to rebalance them every 2-3 months. wtf?

Evo_Jay

iTrader: (17)

What??

Giving the fronts more air then the rears PROMOTES understeer.

Your right, there should be a discrepency, but the other way around.
More air in the rear and less in the front help get rid of udersteer, which we know the EVO has a lot of.

I run around 32 in front and 35 in the rear.

mathgeek

Check the sticker on the driver's door. Recommended air pressure is 32 front and 29 rear. I'm just going with what Mitsubishi recommends. There is obviously a reason.

Evo_Jay

iTrader: (17)

^^
Well you said for best performance, which the factory recommondition is not.
When you said the recommend pressure, I thought you meant for performance, not factory recommendition.

mathgeek

I assumed that the recommended pressure is optimal for performance. Why would recommend otherwise? That being said, I would like to know what the best tire pressure is so that I can use it. Can you tell me why your settings are what they are? And are they noticeably better than what is recommended, per your driving experience?

Evo_Jay

iTrader: (17)

Mitsu recommend what was best, but not neccissarly best for handling.

Look at this chart of handling. Even though its for compition tires, the stuff still holdsi.e. less psi in the front tires reduces udersteer, etc.

http://www.tirerack.com/tires/tirete....jsp?techid=58