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Car feels very unstable

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Old 02-08-2012, 03:54 PM
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Default Car feels very unstable

I've got an 02 Z and I've noticed my car feels very unstable while driving. The car wants follow all the groves on the road almost like my car is on tracks. It leaves me having both hands on the wheel almost fighting the car on bumpy roads. What is going on with my car?

Some things to note, my car is on DMS springs, Koni yellows, Michelin PS2's in the front, and Sumitomo HTR Z III rears.
Old 02-08-2012, 04:04 PM
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Did you have the car aligned after you lowered it. I found spinning each outer tie rod one rotation in (towards the motor) helps tremendously
Old 02-08-2012, 04:25 PM
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Originally Posted by VinR1
Did you have the car aligned after you lowered it. I found spinning each outer tie rod one rotation in (towards the motor) helps tremendously
I will be getting an alignment within a month after I get new tires. I'll try spinning the tie rods in the meantime
Old 02-08-2012, 04:30 PM
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Like VinR1 said it definitely sounds like the car needs to have the alignment checked.
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Old 02-08-2012, 07:42 PM
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Some have said in previous threads on the same topic that it can also be a result of the tire width -- what do you have?
Old 02-08-2012, 08:10 PM
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Originally Posted by libertyforall1776
Some have said in previous threads on the same topic that it can also be a result of the tire width -- what do you have?
+1, do you still have the stock wheels and tires on the car?

My car with the stock 275's up front tends to follow the grooves in the road quite a bit. Gets kind of hairy at times when the road gets uneven, the car will just try to go wherever the grooves are going.
Old 02-08-2012, 08:46 PM
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In addition to the toe, try getting all the caster that you can get. I maxxed out my caster and I can drive down the road with one hand on the wheel. I also have -1.4 camber in both front wheels and zero toe. My car used to follow grooves but now it's not near as bad as it used to be. I'm also running 275s on the front.
Old 02-08-2012, 09:09 PM
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Like everyone else said, get an alignment and new tires. Tracking gets worse as the tire wears also.
Old 02-09-2012, 12:56 AM
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Originally Posted by libertyforall1776
Some have said in previous threads on the same topic that it can also be a result of the tire width -- what do you have?
Sorry, I should have mentioned that. I have 275/35/18 in the front and 285/35/18 in the back. My new set of tires will be Nitto Invo 275/35/18 and 295/35/18

Originally Posted by TransAmWS.6
+1, do you still have the stock wheels and tires on the car?

My car with the stock 275's up front tends to follow the grooves in the road quite a bit. Gets kind of hairy at times when the road gets uneven, the car will just try to go wherever the grooves are going.
I do not have stock wheels and tires. I have 18" rims all around with 9.5" width in the front and 10.5" width in the back with +50mm offset on all of them.

Originally Posted by ChrisRZ28
In addition to the toe, try getting all the caster that you can get. I maxxed out my caster and I can drive down the road with one hand on the wheel. I also have -1.4 camber in both front wheels and zero toe. My car used to follow grooves but now it's not near as bad as it used to be. I'm also running 275s on the front.
I will be taking my car to a shop that specializes in aligning lowered cars, but I will let them know to max out the caster.

Originally Posted by soulless
Like everyone else said, get an alignment and new tires. Tracking gets worse as the tire wears also.
Yeah, I will be getting all that done soon. Hopefully my car will start steering in the direction I want it to go.



Will I need to buy anything for the alignment? Some people are telling me I need to get a camber kit since I got a lot of negative camber after I lowered my car.
Old 02-09-2012, 01:32 AM
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Following the grooves in the road was the first thing I noticed when I bought mine. It came with 275s. I don't even notice it now.
Old 02-09-2012, 05:54 AM
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I would recommend max positive caster, max negative camber and either no toe or the tiniest increment of toe out. All of the settings should be symmetrical, "max" will not be the same on both sides. Fair warning the, the more outward you go with the toe, the more she's going to want to turn. I have my car with just a tiny bit of toe out and I like it, bit its not for everyone. . mine is also with 275s up front.

It its the heavy inward toe that makes it less responsive to driver input and makes it track grooves. GMs way of idiot-proofing?



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