Steering wheel vibration

[nuteman]

Hi All,

My 1973 240Z steering wheel shakes considerably between 45 and 65 MPH. It smooths out at speeds greater than 65 MPH.

Is this a wheel balancing and/or wheel alignment issue?

I guess I'm perplexed by the fact that the shaking lessens at higher speeds - If it was balance or alignment wouldn't it get worse at higher speeds?

Thanks in advance for any info/advice.

[240ZX]

nuteman, with a car of this age it's difficult to pinpoint the exact reason for the problem you are experiencing. Possible candidates that usually require replacement are as follows....all rubber suspension bushings, steering shaft coupling, steering rod end bearings, and steering rack bushings. Wheel bearing may be in need of repacking and adjustment. As you memtioned, tire/wheel balancing. What I'm trying to say here is, that with a 30+ year old car, you have to go through the exercise of eliminating potential problems one at a time. You will be much happier with the way your z drives after you replace these worn out parts.....we've all been through this exercise ourselves. Good luck and tell us what you find.

[NCLarry]

Almost twenty years ago (the last time I had a running Z) my 280 did exactly that in about the same speed range. I recall, new tires, balancing, alignment, etc. never corrected. I had accepted it as 'usual'..

Others? Was this the case when new?

[Bambikiller240]

Others? Was this the case when new?

No. There have been several threads about this situation over the past few years. It is usually caused by a combination of worn out parts including (but not limited to)steering coupler, inner/outer tie-rod ends, rack bushings, control arm bushings, ball joints, wheel bearings, un-balanced tires/wheels.

[Ed]

You could start off by taking your car to an allignment shop. Tell them what the symptoms are. More than likely they will inspect all your steering components, balance your tires, and give you recommendations as to what is causing the vibration. You could say thanks but no thanks and fix it yourself or just let them at it.

If it were me I would start with a good balance on the wheels then start replacing all the worn-out rubber. Replace the tie-rods and the ball joints. Then take it to the allignment shop.

I had a vibration in my front end for the longest. Had the wheels balanced several times. Ended up being the rims. They where the type that are "universal" (for different bolt sizes). If you look at the bolt holes they are oblong. So they never sat right. Different rims fixed it.

[EScanlon]

Before you go tearing your car apart, do the following basic checks.

First swap your front tires for the rears, and take the car out for a drive. If the problem has gone away, you need to get the tires checked.

Go to a reputable tire dealer, preferably one where you have done business with, or the one that services the tires you have. Have them do a SPIN balance on the tires. A spin balance over a bubble balance is the only way to truly balance tires. The spin balance may very well cure the problem.

Also have them check the tires for belt separation and failure. I had a pair of tires on a car some time back that exhibited the exact problem you mentioned, when I finally had the money and went in for a front end alignment, and suspension workup, the mechanic called me up and said all I needed was a new set of tires. In my case, the belts in the tire had failed and seprarated, causing this middle speed vibration.

On the other hand, if swapping out the tires from front to back does not alleviate / eliminate the problem (you might find that the shaking now comes from the back end), you then can address the suspension, alignment, etc.

2¢

Enrique

[cremmenga]

My 72 240z also shakes, but it is at higher speeds and not 30-60mph, just wondering if you think it is basically the same problem? and what to start with first. Thanks Guys

[my_mad_z]

I had the same problem with my 260z. I ended up getting an on-car wheel balance and I never had a vibration problem again. This was the wrong way of fixing the problem, but as mentioned in a previous post, it could be a number of things that are worn that are contributing to the vibration.

The problem with getting an on-car wheel balance is that once you remove the wheel, it must go on exactly the same way it came off, otherwise the balance is thrown off.

It's a cheap alternative to rectify the problem but not the best way! I've made sure that this time I won't have vibration problems in the 240z; i've replaced all rubbers and bushes and also changed the wheel bearings.

Hope you solve the problem.

Marc.

[cremmenga]

how much of a pain was it to change all the bushings and etc, and how much $ ? thanks

[Marty Rogan]

Well, its a big PITA to change the bushings, but well worth it. You can get a set of polyurethane Energy Suspension bushings (Master Kit) for between $135 - 150 on ebay.

Installation can be done yourself if you are handy. Do a search on the website for bushings, as it has been discussed a lot. I am in the middle of my second suspension rebuild and it can be time consuming if you have to do it part time.

If you take it to a mechanic, they will likely charge around $1,800 for the job. Maybe less depending where you are in the country and if you shop around.

Marty

[72' 240]

Nuteman,

Tell me if this NAILS IT!!!

I have one solid rolling 240 (when the engine is running...and that's my problem).

I went through SEVERAL angles with my shaking wheel. It would seem to vary only slightly. It occurred at the speeds that all of you have mentioned. I tried everything that I've seen listed so far with great frustration. It was always still there no matter what I tried! It got so annoying that I just did not enjoy driving the car that much. I got stuck in it one day for quite a long drive (25+ miles). When I got out, the front right (It could be either or both) caliper seemed a bit too hot for the amount of breaking that I had done. I then KNEW it was BRAKE RELATED!

As you know, your pads NEVER lose "slight contact" with the rotors as the car is driven. They are designed that way. The problem occurs when the "slight contact" is too great; it developes heat; enough heat to warp and swell-up the rotor, and even overheat (believe it or not)the whole caliper set. Mine ruinedtwo caliper sets before I found the cause. This higher than normal heat closes the tolerances, and exaserbates the problem. It starts a chain reaction eventually resulting in a warped rotor that encounters the pads at every revolution ("high spots") causing a slight drag that is transfered to the steering wheel as a shake!

Many times my wheel felt fine until I built-up sufficient heat to close the tolerances, which began a GRABBING that felt JUST LIKE a severe balancing or other front-end problem. This does not get better as you apply your brakes or bump the pedal, etc.

The fact may be that the car is performing perfectly...what I mean is that

IT IS DOING EXACTLY WHAT IT IS SETUP TO DO!

Follow me here-

The 240 and some later models have not 1 but two (2) BRAKE BOOSTER ADJUSTMENTS!!!

Many of you may already know about this. There is the one that All of us are aware of at the pedal, and shaft... but there is also one (hidden) between the brake booster and the Master cylinder!

Carefully remove the master cylinder, and notice that the "plunger" coming out of the booster HAS WRENCH FLATS ON IT!

Be careful not to let the plunger fall, or get pulled out of the booster. This can become a MLSB ("Major League Set-Back"). If you simply and carefully screw the tip of the "plunger" in only a 1/2 - to 1 turn to start with, (thus shortening the plunger) you will in effect cause the "resting" position of the booster to be looser. This will release your braking system (at rest)!

You probably will not notice any difference in the throw length or feel at the pedal when braking. JUST NO MORE SHAKE!!!!

Nuteman, I sincerely hope that this has helped you and a few others. It was a "life changing experience" for me. Now please, if anyone can help me with my "Idles, but sputters at slight throttle-up" problem listed on this site, I will be forever indebted to you...

[cremmenga]

I bought a bushing kit tonight, just wondering what i have to do to install it. Jack up the car and go at it, or are there certain things you need to do to get the old bolts and such out? I have searched but found nothing, please help. Thanks