coil spring seats

[spasm3]

I've seen that some cars have rubber or polyurethane spring seats on the bottom of the spring, isolating it from the strut body. Saturn springs sit right on the metal from the factory. Monroe sells a spring seat for this car, but are they necessary? If the engineers did not spec one from the factory, what is the effect if you add one?

This is the one from monroe.

 

[JHZR2]

I just did struts on my saab, and they provided zinc rings. I believe they can be used for noise and/or moisture standoff reasons. In my case it looks like they are used as a sacrificial item.

 

[spasm3]

I was wondering if they damped vibrations. I do wonder since they have some thickness, if they will stiffen the ride by compressing the spring by 1/4 to 1/2 inch.

 

[JHZR2]

That would be sensible. For real coil springs, Ive heard of people selecting different pads to slightly change ride height. At least some vendors like MB have different ones for different purposes.

 

[yonyon]

Originally Posted By: spasm3
I was wondering if they damped vibrations. I do wonder since they have some thickness, if they will stiffen the ride by compressing the spring by 1/4 to 1/2 inch.


I don't see how they could compress the spring any while in use because they're not adding any extra weight. They might raise the ride height a hair though. Maybe they're made for noise control?

 

[cjcride]

They may also reduce rust that would happen at the contact point of spring to strut.

 

[spasm3]

Would most of you use them if they were not there from the factory?

 

[spasm3]

Originally Posted By: yonyon
Originally Posted By: spasm3
I was wondering if they damped vibrations. I do wonder since they have some thickness, if they will stiffen the ride by compressing the spring by 1/4 to 1/2 inch.


I don't see how they could compress the spring any while in use because they're not adding any extra weight. They might raise the ride height a hair though. Maybe they're made for noise control?


I think the strut rod length dictates the ride height. The spring would be compressed because the pad takes up 1/4 to 1/2 inch between the perch and the bearing.

 

[yonyon]

The ride height comes from the spring's compressed length not the rod length. If the strut mount tears you can pull the rod up right through the hole in the hood but the ride height remains the same (while stationary) because the spring supports the weight of the car. If you then add weight by sitting on the hood, the additional weight will compress the spring and lower ride height.

 

[spasm3]

Originally Posted By: yonyon
The ride height comes from the spring's compressed length not the rod length. If the strut mount tears you can pull the rod up right through the hole in the hood but the ride height remains the same (while stationary) because the spring supports the weight of the car. If you then add weight by sitting on the hood, the additional weight will compress the spring and lower ride height.


I see, I understand what you are saying now.

 

[spasm3]

Should i use them?

 

[doitmyself]

I looked up your struts at the Monroe site and their table indicates that those rubber seats are for the UPPER mount.

A look at their Quick Struts also appear to show no rubber seat at the spring bottom.

http://www.monroe.com/en-US/catalog/e-Catalog

Monroe uses the term "lower spring isolator" if a strut had that part.

 

[spasm3]

Originally Posted By: doitmyself
I looked up your struts at the Monroe site and their table indicates that those rubber seats are for the UPPER mount.

A look at their Quick Struts also appear to show no rubber seat at the spring bottom.

http://www.monroe.com/en-US/catalog/e-Catalog

Monroe uses the term "lower spring isolator" if a strut had that part.


Thanks, I had no idea is was for the upper.

 

[doitmyself]

Summit also indicates that this is for the "Front upper coil spring seat."
http://www.summitracing.com/parts/mon-906928