Which Suspension Components Affect Steering Feel?

[The Critic]

The car is a '96 Saturn SL2 with about 140,000 miles. I'd say about 85% of these miles were accumulated through short-distance city driving.

The "steering feel" on this car is heavy, but lately, it seems like the on-center "dead spot" of the steering seems to have gotten worse. In other words, it feels like the steering has a moderate amount of "play" in the 12 o'clock position.

So far, I have checked the following items:

The outer tie-rod ends show no play-- if I grab and rock the front tire at the 9 and 3 positions, there is no play. No cracks at the outer tie rod ends.

The front sway bar bushings do not have any play do not show any cracks.

The lower-control arm bushings do not show any cracks. The ball joints, which are permanently attached to the lower control arm assembly, do not have any play.

The upper strut mounts were replaced 20k ago with KYB units. No issues there.

The wheel bearings do not feel rough, nor does the wheel have any play. No clicking noises from the CVs either.

Although this is unrelated, the rear sway bar end links were replaced 30k ago with Moog parts.

So, I am not sure how to fix this "play" in the steering. All cars have sort of a dead spot in the steering near the 12 o'clock position, but this one seems to have gotten worse lately. Not even to be dangerous, but enough for someone picky like myself to notice.

If it helps with the diagnosis, when I wait in a drive-thru line and slowly "creep" in line, I will hear a clunk/pop from the front suspension. Also, if I hit the brakes to slow the vehicle from 55 to 40 mph, the steering wheel would vibrate. And the vibration ONLY occurs between that window and not at any other time. (For instance, I can hit the brakes to slow the car from 70 mph to 60 mph and there would not be any vibration).

I have been unable to pinpoint the source of the clunk, but someone suggested that it is possible that the lower control arm bushings are worn (despite showing no cracks) and would explain both the clunk and the loss of steering precision. As it was explained to me, many BMWs go through lower control-arm bushings quickly and when they fail, they exhibit noises and loose steering. Therefore, he suggested that I consider replacing the lower control arms (which include a new bushing and permanently attached ball joint).

So overall, I have three problems: play in the steering wheel, clunk during low-speed driving (i.e. drive-thru line), and vibration when braking from about 55-40. What do you guys think?

Thanks!

 

[L_Sludger]

did you check the ball joints with the hub at ride height?

 

[Herz]

could the play in the steering be a worn gearbox? I know my jeep has manual steering and the gearbox is worn down, massive play in the steering 1/2 turn.

 

[willix]

A worn rack will give you a heavy feel usually at the center/straight ahead position or close to the wheel being in the center. As the seal passes over the worn spot in the rack cylinder the seal leaks/bypasses the oil causing momentary failure of the power assist. It can be hazardous have to put muscle into the wheel and then it frees up abruptly.

 

[Kiwi_ME]

Increased on-center deadness sounds to me like your toe-in has changed slightly towards the negative direction (toe-out.) Perhaps a bolt holding a bushing has loosened, allowed it to slip, causing the noise and altering the toe value?

The resonant vibration is also likely to be either directly related to the above, or due to the uneven tire wear that is likely to be occurring.

 

[ryan2022]

I would take a look at your front tire pressure, take it in for a 2 wheel alignment, and as a bandaid, and fairly cheap solution, upgrade the steering rack bushings to Poly Urethane.

It could very well be a slightly worn steering rack, but an alignment and these other things should help.

 

[The_Jeff]

Originally Posted By: L_Sludger
did you check the ball joints with the hub at ride height?


+1

I know it goes against your evaluative instincts but just do both LCAs. Rockauto has the passenger side Mevotech on closeout for $18 though the driver's is still $35. Yes you can probably guess the country of origin. I bought a Dorman/OE from rockauto 2 months ago that is visibly different in construction from the "OE" I got off ebay 3 years ago (follow this?) that wore out in 35k. (Do I ever learn?) Anyhow your level of quality received probably follows price. I bought the Dorman based on name recognition though they appear to also be in the rebadging business.

Having had enough s-cars with bad ball joints, your "sloppy center" was one of my symptoms to a "T". Remember you get new LCA bushings with the changeout; I had one of those go soft and the tire rolled fore and aft which changed some other geometry and led to the car blowing all over the road.

You can also work at popping one side out of the steering knuckle non-destructively. Usually takes a six foot pipe prying down on the sway bar, with the end under the subframe, tapping the BJ with a hammer. Then you can check the shank; a good BJ shank will stand erect with friction while a bad one will flop over. A really bad one you can spin freely in the joint.

The "6 and 12 wheel shake" technique isn't real good on these cars. You can also try prying between the knuckle and joint, while feeling the castle nut with your other hand. Slop will show up as a vibration in the castle nut.

Having pulled steering racks from these cars I'm pretty sure they're solidly mounted, no bushings.

 

[mechtech2]

What you should do is have the car on the ground, and have someone wiggle the steering wheel back and forth rapidly about 1-2 inches.
Then, you can see what is moving and NOT moving underneath.
Something you think is good may be not!
Also check the steering rack mounts, and steering column joints.

 

[mechanicx]

Maybe the clunk or pop is just the rotors are slightly warped? It could be something else though like a CV joint or powertrain mount. The on-center feel and play in the steering could be that the rack is worn and the pinion preload is off. It would be hard to adjust it with the rack in the car. Is there always play in the steering even at a stand still? The toe could be off, but that usually shows up eventually in tire wear.

 

[artificialist]

If your vehicle has too much positive camber, caster, or SAI, steering effort will increase.

However, if the vehicle is in allignment, I would bet that your P/S rack leaks internally to creating more steering effort, or the rack gears are work, causing free play.

A failing P/S pump could leak internally and raise steering effort.

Check your allignment paperwork if it has been done recently.

Otherwise, get an allignment, and hope that it lowers effort.

 

[The Critic]

Originally Posted By: mechanicx
Maybe the clunk or pop is just the rotors are slightly warped? It could be something else though like a CV joint or powertrain mount. The on-center feel and play in the steering could be that the rack is worn and the pinion preload is off. It would be hard to adjust it with the rack in the car. Is there always play in the steering even at a stand still? The toe could be off, but that usually shows up eventually in tire wear.


Yes, there's definitely play in the steering even at a standstill, if you mean by standstill when the car is off. It isn't a lot, but seems on the higher side of normal.

Originally Posted By: artificialist
If your vehicle has too much positive camber, caster, or SAI, steering effort will increase.

However, if the vehicle is in allignment, I would bet that your P/S rack leaks internally to creating more steering effort, or the rack gears are work, causing free play.

A failing P/S pump could leak internally and raise steering effort.

Check your allignment paperwork if it has been done recently.

Otherwise, get an allignment, and hope that it lowers effort.


I've had like five alignments in the last 10,000 miles and I'm certain that my alignment is still spot-on.

Maybe I should do both lower control arms, tie rod ends and a new rack?

 

[The_Jeff]

Leave the rack alone for now. TREs are so cheap and easy you may as well do them as part of a full rebuild, just for the convenience of only getting one more alignment, and having greasable parts. Yet I still believe it's your LCAs.

If you really want to test your rack have an assistant wiggle the steering wheel on center while you hold the tie rod (not end, just the middle part). If there's slop in the rack you'll feel a vibration without movement or on transition from turning the wheel one way to the other. Tight rack= you'll feel "well connected" movement.

You can also start turkey baster changing your PS fluid with something like M1 dexron atf.

 

[mechanicx]

Originally Posted By: The Critic
Originally Posted By: mechanicx
Maybe the clunk or pop is just the rotors are slightly warped? It could be something else though like a CV joint or powertrain mount. The on-center feel and play in the steering could be that the rack is worn and the pinion preload is off. It would be hard to adjust it with the rack in the car. Is there always play in the steering even at a stand still? The toe could be off, but that usually shows up eventually in tire wear.


Yes, there's definitely play in the steering even at a standstill, if you mean by standstill when the car is off. It isn't a lot, but seems on the higher side of normal.

Originally Posted By: artificialist
If your vehicle has too much positive camber, caster, or SAI, steering effort will increase.

However, if the vehicle is in allignment, I would bet that your P/S rack leaks internally to creating more steering effort, or the rack gears are work, causing free play.

A failing P/S pump could leak internally and raise steering effort.

Check your allignment paperwork if it has been done recently.

Otherwise, get an allignment, and hope that it lowers effort.


I've had like five alignments in the last 10,000 miles and I'm certain that my alignment is still spot-on.

Maybe I should do both lower control arms, tie rod ends and a new rack?


Do you have any fluid leakage? Air in the system can make the steering sloppy while driving. If you have play in the gear, I'm betting your rack is worn out. If there's no play in the outer tie rods then there's no real need to replace them now but it might be good preventive maintenance.