ok maybe someone has this problem before.

This may also be a dumb question.

When I drive around 75-80+ mph and keep the speed steady, the car has a weird pulseating vibration that seems to move from the front end of the car, through the steering wheel, into the seat and then repeat all over again in a matter of about 5 seconds. Kind of slow and steady.

It does not really seem to do it at slower speeds and goes away for a minute when excellerating and then coasting. I know that my mechanic has told me that the tie rod on the front passenger wheel needs to be replaced, I trust him and he is a really good guy and mechanic.

My question is if there is anything else that could be causing this besides unbalanced tires or misalignment. I know it is kind of a "my car won't work, what's wrong?" kind of question, but I was hoping that someone had some advice as to what else should be checked and also where I might find info on how to fix it. I'd like to make sure that nothing horrible is going wrong with my car.

Thanks for all the help.

The car is an 83 S model with AT and the tires are all stock sizes and match, no larger in rear than front or any weird offsets of the kind, extremly stock (for now ). I do have a copy of the WSM's on pdf but dont really know how to find things in them yet.

 

Sounds like tires to me.

 

I had a similar vibration with that very odd 5 second period, not once but twice. It was tire balance on a new set of tires both times. Mine was in the rear. One wheel was off an ounce. Tires were done on the same computerized balancer, but some guys do it better than others. I had stock rims too. Maybe you lost a weight on one rim.

 

Thanks a lot guys, I will check it out asap.

So nobody thinks its tie rod related? Just curious how long I can let it go.

 

Tie rods and rack bushingas are easy to check. Jack up a wheel and try to wiggle it side to side, up and down. If it wiggles side to side, lay underneith and see what's moving. It could be inner or outer joints on the rods, the rack, or the rack bushings. It's best to lift both fronts at once, but you can do them individually. If nothing wiggles, it probably wheel/tire like was suggested.

 

My vibration was rather subtle, came at 80 and dropped away at speeds higher than 95 (heh, have fun testing that!). It's easy to check tie rods for play.

http://www.nichols.nu/tip335.htm

Oh, you have an 83...uhoh. Can I assume you have had the aluminum balljoint carriers replaced?
http://www.nichols.nu/tip523.htm

 

BTW, if you have Jim Morehouse's version of the WSM, there is Table of Contents w Links.pdf that is clickable to any item listed in the contents. Best to just read the whole WSM like some people read the Bible - cover to cover.

 

Tie rods will generally not cause vibrations of the type you are describing. You would first notice steering play and wander, then if it gets bad enough some vibration. Wheel bearings could also do it, but usually not the cause. Use Flyingdog's suggestion to check.

I am finding more and more that the source of these vibrations is tire/wheels related and prople spend far too much time and money on swaping suspension components just to track down these annoying vibrations. Do yourself and your wallet a favor and have the wheels road-force balanced. I was talking to the manager at the local Discount Tire shop (when I took my brand new tires back to be rebalanced - but this time road-force balanced), and asked him how often they calibrate their standard balancing machine. He said every couple of days!

The nice thing about the road-force balance system is that it measures teh balance of the wheel to the tire and tells them how to mount the tire to the wheel for optimal balance. It also measures the radial and lateral runout of the wheel so you will know if your wheels are straight and true. Make sure they use the scratch guard face plate when they do it otherwise the balance will be off!

Since having my wheels road-force balanced (plus the motor mounts), the ride is like butter. FYI, they usually charge about $20 a wheel, but if you negotiate, you should be able to get it for half.

 

Road force analysis is the way to go. You might discover a bent wheel in the process, possibly two. G