How much backlash is normal in steering?

[PandaBear]

Previously you guys and I mentioned that I might have a loose tie rod in my car because the 3/9 O'clock location has movement of 5mm or so at the trend of a 14" tire. Today I found some time to check under the car with both front wheels off the ground. The entire system from left tie rod end to right tie rod end is rigid when I try to shake left to right. It seems like the entire system has a backlash that is inside the rack or the steering linkage. How much is usually acceptable?

Similarly it seems like every FWD car I've seen have wheel rotation backlash if the other wheel is on the ground, by about 10 degrees or so. How much is usually normal?

 

[Eddie]

My FWD Mazda CX7 has about 1/2 inch at the streering wheel.

 

[BetaBear]

Some slight play in the steering left to right before you hit resistance is normal.

What is the vehicle? If it doesn't have a rack&pinion but a haltenberger type of setup like on some trucks/SUV's, backlash is adjustable via a locknut and adjusting nut.

When you lifted the vehicle, and supported it on jackstands by the body/frame to let the pressure off of the suspension, did you shake down the wheels? Shaking the wheel/tire left and right, and then up and down can tell you a lot. There should be no clucking play, it should be solid, and left and right should be tight. if you get clucking back and forth while shaking the wheel, you can now look and determine whether it is steering related, suspension related, or wheel bearing related.

5mm is nothing in play of the steering wheel. If there is no vibration issue when traveling at highway speeds with the steering wheel or vehicle, Its likely that there isn't an issue.

What you want to watch for when steering is look at the tires. when the vehicle is sitting and engine on, point the tires forward with the steering wheel straight. look at the wheels and turn left to right slowly within the 5mm "Play" area. if the wheels are instantly responsive (the 5mm area of play won't turn the wheel but a little bit. your not looking for much.) then you are probably fine if the shake-down test passes. usually up to 2 inches of spread at the steering wheel before resistance is met in a haltenberger type setup is normal, provided the tires are instantly responsive and passes a shakedown of the wheels.

 

[eljefino]

Originally Posted By: BetaBear

What you want to watch for when steering is look at the tires. when the vehicle is sitting and engine on, point the tires forward with the steering wheel straight. look at the wheels and turn left to right slowly within the 5mm "Play" area. if the wheels are instantly responsive (the 5mm area of play won't turn the wheel but a little bit. your not looking for much.) then you are probably fine if the shake-down test passes. usually up to 2 inches of spread at the steering wheel before resistance is met in a haltenberger type setup is normal, provided the tires are instantly responsive and passes a shakedown of the wheels.



This. Also if you have loose tie rod ends the ball and sockets will have the most wear at ride height and the least with the suspension unnaturally drooping.

 

[mechtech2]

No freeplay is normal [and right].
Even steering racks usually have a tensioner spring or shims.

 

[PandaBear]

The vehicle is a 97 Acura Integra.

There is vibration issue due to some tire wear (minor cupping due to worn bushing, I assume) and some minor toe wear (2/32" difference between inner edge and outer edge.

A solid "thud" if I shake a lifted wheel left and right when both front wheels are off the ground. No movement at all if one wheel is on the ground and one wheel is off. Steering is very sharp, no noticeable "looseness" play in the steering if the engine is in idle and car not moving.

I guess everything is fine?

 

[BetaBear]

There should be no thud at all with the wheels off the ground. If you have a worn bushing this could be your vibration issue as well if it is in the steering while driving and the steering wheel shakes a little.
Originally Posted By: eljefino
This. Also if you have loose tie rod ends the ball and sockets will have the most wear at ride height and the least with the suspension unnaturally drooping.


Yes, but you can check for play in the control arm bushings much easier when there is no load on them. its also more difficult to check for play in the ball joint on the lower control arm if the vehicle's weight is pushing on it.

 

[PandaBear]

I heard many things like preload needs to be adjusted:

http://www.valvoline.com/car-care/automotive-system/steering/ccr20060701sr

Can it be the preload needs to be adjusted?

 

[BetaBear]

I could need adjusted. You can always adjust it to see. To adjust the backlash, you loosen the locknut that is around the hex/allen key in the middle, keeping your allen or hex bit in there to prevent it from turning. Turn the hex screw to tighten only about 1/8th of a turn and hold it there. Tighten the locknut back up.

You can do all of this while the vehicle is on the ground, but to check for play, the engine has to be on. turn the wheels lock to lock to check for binding, and take it on a short test drive. if it binds, it's too tight, and you must back it off 1/8th turn at a time until it stops binding.

It should be tightened to the point where there's none-to-minimal slack, but not so tight that when turning, the steering wheel won't return back to center on it's own. This is just a hair too tight, and needs to be backed off a little bit. When you've done it, the steering should feel tight, but smooth like a new car.

Did this on the Jeep's steering just last week actually. I had play from about 10.5 o'clock to 1.5 o'clock on the steering, and now it's about 1" left and right of play from center. It's tight and responds within this window, but not tight enough that I have to manually return the steering back to center after a turn.

 

[eljefino]

I have not heard of success tightening steering racks. Boxes, yes, but not racks.

 

[440Magnum]

The issue the OP is describing almost sounds like the bushings that secure the rack to the chassis are shot, allowing the entire rack to move relative to the chassis. Been there, seen that. Easy fix (depending on where the rack is located... wouldn't be so easy on some minivans, I guess.)

 

[mechtech2]

The problem with adjusting racks is that you can tighten them up easily , but then they will stick/bind in the other regions of travel.

This is because the most used section is in the center.

 

[crazyoildude]

i always tighten boxes