Bad front wheel hop on my Z? need advice.

[redsx13]

Hi, i have an 03 350z w/ a little over 40k on it. And i cant seem to figure out why the whole car will shake (which seems to be coming from the front)under hard cornering. the car has the oem shocks, oem rims, and tien lowering springs, but the shocks still seem fine. the car seems to shake the most at the point ware thare is mild understeer while cornering very hard. any advice?

thanks

[rmezz13]

hmmmm..... i'm clueless. so its only during hard corners? Everytime? Lets go real in depth on this one until someone else chimes in.

[audtatious]

First thing to do is replace the stock struts. While they may seem fine it sounds to me like they are actually blown.

[R350Zz33]

i would throw some tien shocks to go with the springs because u lowered the car and put more stress on the shocks

[AZhitman]

Yep - They're shot.

Stockers don't like to be compressed beyond their original range, and that's what's happened.

There's also some cases I've seen where the shock piston "binds" laterally on the compression stroke during hard cornering, which results in some weird "shudder" transmission up through the wheel.

Time for some aftermarket struts.

[redsx13]

I was actually thinking the same thing. i got some tokico's for it, so i'll throw them on and let you guys know what happens

its just strange, cuz they look and feel totally fine. no leakage, no tears, no other symtoms.

[AZhitman]

Hard to see leakage when they're filled with gas.

[evildky]

"wheel hop" generally is used to describe what happens when power is applied to a wheel and the wheel "hops" for lack of traction and dampening

Your issue might well be the shocks, when you lowe the car you put the stock shocks beyond their happy zone, you are also applying more spring rate to the dampers than they were intended to handle

Also be sure to check your bearings, balljoints, and tie rods

[redsx13]

Just replaced my all my stock shocks with some brand new tokicos but I still have the same problem! i also checked all my front end bushings, and they are all fine. no visable signs of wear. the shocks did seem to help a little at first, but now the problem has gotten worse, wayyy worse. now it happens on every turn, the windows rattle so bad it feels like they are going to break! could it be my tires? help!

p.s. just to let you guys know, my car has never been in a accident of any kind

thanks

[R350Zz33]

how old are the tires how much wear did u get a new alignment ?

[rmezz13]

i almost wonder if they are directional tires and are on backwards?.... tire shops fault..... i would take them up where you got them, explain the problem, then kick someone in the butt for messing up your ride.

[redsx13]

well, the tires were put on a while ago and are very worn, so im kinda on my own with this problem, i dont really think its the tire shops fault, the tires are directional but they are on the correct direction. i can go 100mph and it will be as smooth as glass, until i take a turn. (not at that speed of course)

it may also have somthing to do with front camber, i have michlin pilot sport 225/45/18's on the front and most of the wear is on the outside of the tires. they are inflated to 35psi and they have alot of wear on the side walls. it seems like they are rolling over in hard turns. either i dont have enough front camber, or 45 sidewalls are too big for the type of driving i do.

What do you guys think?

[evildky]

sounds like you got positive camber? which is the opposite of what you should have from your lowering springs? car been hit? the sensation of movement in the frotn wheel makes me suspect a ball joint or wheel bearing issue, perhaps even a TC rod, have you checked them both with and without load?

[rmezz13]

take it to someone that knows what they are doing. tell them your problem and see what they charge to look at it. i mean if you don't know what to look for, maybe they could give you a ball park on what to replace, or even exactly what needs fixed/replaced. that would be my best advice i guess.

[rmezz13]

did you get an alignment when you replaced the shocks?

[redsx13]

sounds like you got positive camber? which is the opposite of what you should have from your lowering springs? car been hit? the sensation of movement in the frotn wheel makes me suspect a ball joint or wheel bearing issue, perhaps even a TC rod, have you checked them both with and without load?

no positive camber, you can tell just by looking at it. the car has also never been hit. i would like to check the ball joints, i know how to do it, but im not quite sure ware to jack the car up from to do it.

I didn't get an alignment when i replaced the shocks. I know i should have. but i want to get my front camber situation figured out before i spend the money on an alignment. like i said, my tires are wearing in the outside. since my car is lowered, it has a good amount of negative camber. are 45 sidewalls too big for the type of driving i do? or do i not have enough negative camber?

[redsx13]

help! I just bought all new tires 245 40 18/ 265 40 18, and i still have the same problem. i cant figure it out, i need some more ideas.

thanks
Modified by redsx13 at 7:40 PM 7/19/2008