Coil Spring Worn Out?

[s199810]

QX4 1999, replaced strut and shock absorber myself in less than one year. Last week I drove down (a little bit fast) a bumpy slope and turned left and I lost control of steering, the car ran onto the opposite lane. and I have noticed for a long time that whenever I drive down a slope on a little bumpy road, once the car gets bumped, the car moves sideways also. I measured the ride is about 1" lower than spec. Does this have connection with the steering problem mentioned above? Myself is more like to believe to replace the coil spring but just need confirmation from some experienced guys here. any advice where to buy a good coil spring? Could a new coil spring improve the steering problem a lot? thanks

[Towncivilian]

Have your QX4 inspected for the strut housing corrosion recall. Worn coil springs would not cause you to lose steering control.

The side-to-side movement might be worn rear control arm bushings.

[s199810]

yes, my QX 4 was inspected for the strut housing corrosion recall last year before I replaced the strut and shock absorber. thanks for your reply and I will check the rear control arm bushings. but I feel it's something with the front suspension because when the front wheels are hitting a bump when steering, I can feel a short time that the front tires jump off the ground and that's causing the side movement, and the bigger bumps, the bigger side movement. one thing for sure is that as long as the front wheels stay on (better stick) the road, there is no side movement. To accurately descibe this side movement, it's the front of the car moves sideway, not the whole car, it's like small spining around the rear wheel. Next time I will try to find a empty parking area and drive fast on a bump and steer the car and see what happen, of course not too fast to turtle my QX4.

[Towncivilian]

Check your tie rod ends for play. Next time you've got it on a lift, check for axial play on the wheels and the other front end components (ball joints, control arm bushings, etc).

[s199810]

in addition, I have no problem driving on highway, no sway or whatever. Also when I hit a bump when going straight, no side movement/spinning problem also.

[Towncivilian]

It sounds more like a front end component issue, then. Since you don't have any sway at highway speeds, your rear control arm bushings are likely in good shape. Is one side of the vehicle lower than the other, or is the vehicle completely level but just lower than the specified stock height?

[s199810]

thanks a lot. just measured the arch height, front left 30.5", front right 31.25", rear left 31.5", rear right 32". obviously the left side is about half inch lower than right side.

[Towncivilian]

Naturally the driver's side front coil spring would get more worn given the driver weight is closest to that side, along with the steering column etc. I'm fairly certain it's not causing your steering issue assuming the coil spring isn't binding or bent out of shape or anything.

[s199810]

do u think the ride heights are within a reasonable range? just checked the repairing manual 32.09" for front and 33" for rear.

[s199810]

This is like the problem what I am having.

Bump Steer: Occurs when the coach hits a bump and the steering wheel suddenly jerks to one side or the other on its own. Usually caused by improper suspension geometry.
See source here,http://www.hendersonslineup.com/educati ... -problems/

[Towncivilian]

I'd get the front end checked out (strut mounts, steering components, etc). See page SU-3 and ST-5 of the factory service manual for a chart possible causes of suspension and steering issues, respectively.

[Chuck Tribolet]

This is like the problem what I am having.

Bump Steer: Occurs when the coach hits a bump and the steering wheel suddenly jerks to one side or the other on its own. Usually caused by improper suspension geometry.
See source here,http://www.hendersonslineup.com/educati ... -problems/

Bump steer doesn't move the steering wheel, it moves the road wheel to one side as you go over a bump. It is caused by
improper geometry, steering geometry relative to suspension geometry. It's not been a problem on my three Pathfinders ('87, '95, '01) which
indicates that Nissan's engineers are reasonably competent. It could be a problem if you have done a lift or lowering which
would change the steering geometry relative to the suspension geometry.