PLEASE EXPLAIN: Rear sway bar parts!

[DooMer_MP3]

I am just curious through all of this bulls*** with our swaybar noises, about the purpose of the parts involved with it. I've heard of bushings (obviously), control arms, end links and such. What do each of these pieces do? Why would they make noise?

Chris

 

[mazdadan]

The setup of the rear sway bar is actually pretty straightforward. The bar is attached to the rear subframe of the car with 2 sets of bushings and brackets. The brackets clamp around the bushings and the bushings clamp around the sway bar. On each end of the sway bar, there is a hole in which the end links connect. These endlinks attach to the rear struts. On the rear of the car, the control links (referred to as TTL links) are not directly connected to the sway bar. There are a few reasons why these parts make noise. The bushings creak due to lack of lubrication and their size. The movement of the sway bar will grind the bushings down and they will eventually pop out of the bracket or move around loosely in the bracket. In return you get the clunks and creaks. The sway bar end links in my opinion leave much to be desired. They are metal, however the pivoting joint on each end is attached with plastic! There are 4 blue pieces of plastic on each end of the end link. This holds the whole thing together. This is why I built my own with high quality rod ends and threaded rod.

 

[Newf]

But, you have a '01 ES. From what I am told, the endlinks are different on yours.

Although your explanation is perfect!

 

[DooMer_MP3]

Thanks for the excellent write-up. Few questions :

...The brackets clamp around the bushings and the bushings clamp around the sway bar...

Ok, so bushings clamp to the swaybar, and the brackets to the bushings, what to the brackets clamp/attach to if anything? What is the point of bushings in the first place?

...On each end of the sway bar, there is a hole in which the end links connect. These endlinks attach to the rear struts. On the rear of the car, the control links (referred to as TTL links) are not directly connected to the sway bar...

So end-links are what physically attach the sway bar to the suspension, correct? What are the control links connected to then?

Thanks!

Chris

 

[mazdadan]

But, you have a '01 ES. From what I am told, the endlinks are different on yours.

Although your explanation is perfect!

Amazingly, the end links in the ES are the same as the MP3. You would think Mazda would have used stronger ones, but they didn't. When I was modifying my sway bar, there was a local dealer with an MP3 that I took a look under. Unless they have a "revised" end link in the newer MP3s, I'm almost positive every trim level has the same end link.

If you look on Racing Beat's website, they designed stronger end links in the picture, but I guess they did not make it into the production model.

http://www.racingbeat.com/Protege/ProjectMP3/dev1.htm

 

[mazdadan]

Thanks for the excellent write-up. Few questions :



Ok, so bushings clamp to the swaybar, and the brackets to the bushings, what to the brackets clamp/attach to if anything? What is the point of bushings in the first place?



So end-links are what physically attach the sway bar to the suspension, correct? What are the control links connected to then?

Thanks!

Chris

The brackets are mounted to the rear subframe (crossmember) that goes across the rear underbody of the car. This holds the sway bar in place. The bushings are required so that the car is tolerable in everyday driving and to increase the life of the brackets, etc. When I was fixing my suspension, I was talking to a local racecar fabricator and he told me that most racecars do not have bushings. But for everyday driving, the bushings are needed to make the car tolerable.

And yes, the end-links physically attach the sway bar to the suspension. The control links attach the strut/hub assembly to the subframe indirectly. If you look under the car, the control links are the 2 horizontal bars on each side of the car.

 

[DooMer_MP3]

Thanks for clarification Mazdadan. So are you 100% sure that the MP3 uses the same plastic end-link after looking at it? Or just pretty sure? I'd like to include this information in my letter to Mazda North America if you're sure.

Chris

 

[DooMer_MP3]

BTW, how would I go about greasing the bushings? Do they have to be removed to do such a thing?

 

[Grimace]

I'll add another question - is there any aftermarket route to take if we want to upgrade our sway bar or bushings (or both) to get rid of the clunk?

 

[mazdadan]

Thanks for clarification Mazdadan. So are you 100% sure that the MP3 uses the same plastic end-link after looking at it? Or just pretty sure? I'd like to include this information in my letter to Mazda North America if you're sure.

Chris

From looking under one at a local dealer and from the pictures on Racing Beat's website, the end links are 100% identical to the ones on my vehicle.

There is also another site on the web that clearly shows the end links.

http://old.soliton.net/showpic.shtml?http://images.soliton.net/protege/tech/Rear Suspension.jpg

As you can see, the actual end link is metal, however the pivots on each end are attached with 4 pieces of plastic that are molded to the metal....a very weak design in my opinion.

 

[mazdadan]

BTW, how would I go about greasing the bushings? Do they have to be removed to do such a thing?

The stock bushings have to be removed to grease them up because there is no place to physically attach a grease gun.

 

[DooMer_MP3]

mazdadan,
So the end-link in that picture would be the thing that is bolted to the rear swaybar, and to the strut itself, right? And that's plastic? Good god! I wonder if they did anything different on the MSP?

Chris

 

[mazdadan]

mazdadan,
So the end-link in that picture would be the thing that is bolted to the rear swaybar, and to the strut itself, right? And that's plastic? Good god! I wonder if they did anything different on the MSP?

Chris

You got it! The link itself is metal, but the ends that bolt to the strut and sway bar are molded to the link with plastic. You should see 4 little blue bumps on each end...that is the plastic connection. When mine broke, the plastic sheared right off and the link detached from the sway bar.