grunt's bushings

[93Leg-c]

Does anyone know anything about these polyurethane bushings? They're from Australia, supposedly state-of-the-art with the firmness of polyurethane bushings but not the same harshness.

http://www.gruntsbushings.com/index.html

I got the site from Daniel Stern's site which refered to the geocities' website then linked to grunt's bushings.

[Legacy777]

Hmm.....looks interesting....but I haven't heard anything about them.

[93Leg-c]

I wanted to know how they compared with Whiteline bushings so I emailed Mr. Gray this message:

Dear Mr. Gray,

I came across your site through Daniel Stern's site and then through geocities' site.

Your blue polyurethane bushings caught my attention. May I ask how they compare to Whiteline's yellow poly bushings? I am thinking of installing poly bushings on my Subaru Legacy (Liberty in Australia) and I don't want an overly harsh ride.

Thank you very much for considering my question.

Sincerely,


And, this was his reply:

you will not be dissapointed
my blue ones are made from polyester urethane so the have firmness but hardly any extra hardness
Paul Gray
Grunts Bushings
Australia


I was actually hoping for a more technical answer with some sort of testing results to back up the claim of having the firmness but not the harshness of [other] poly bushings. I would think Mr. Gray must have compared his to Whiteline's since the Whiteline bushings are also in Australia.

Now all I need to buy another Legacy and start modding/improving it.

[206er]

my blue ones are made from polyester urethane so the have firmness but hardly any extra hardness

this guy should write infomercials

[scottzg]

I wonder if he is rebadging Superpro bushings? They are also from au, and are blue, and are made from PU. Everything he's selling Superpro also sells for similar prices. Whiteline bushings are made by them.

I have a hard time believing he's a major outfit, judging by the quality of the website and the lack of technical information.

[93Leg-c]

scottzg: Now that's an interesting observation. So, if he is rebadging SuperPro's blue bushings, which seems very possible, my next question is: What's the difference between SuperPro's blue PU bushings compared to the yellow bushings they make for Whitelines? Any supporting documentation anywhere on that comparison?

[Legacy777]

See....that's the thing......he contradicts himself.......How can you have a "firm" bushing, without "hardness"??? That just doesn't work.

Poly bushings are all relatively the same IMO.

Len, what bushings in particular were you looking at?

[93Leg-c]

I was thinking about the steering rack and all of the sway bar bushings.

I realize the contradiction of the bushings being 'firm' but 'not hard.' But I was wondering if he meant his bushings are not as hard as the "other" bushings he's comparing his to or being very technical in saying that his is actually harder but by not very much. It depends on how the wording is interpreted. Or it could mean absolutely nothing at all. (Yes, he may be very good at writing infomercials.)

I was thinking of the comparison of aftermarket performance springs--they lower the car and have increased spring rates but they are all technically different if you look at the specs--I wouldn't go with Japanese-made springs because from what I've read on the Board, they just will slam the vehicle and provide undue harshness in ride in everyday street driving.

And, Josh, while I agree with you that most poly bushings are relatively the same, I wanted to find out the differences, small or great, between the Whiteline and Grunt's/possibly Superpro bushings. Many times I transport senior citizens or those that are not feeling well to the doctor's office and the cumulative effects of struts, springs, tops, bushings, wheels and tires can eventually make a difference for these individuals. So, I'm trying to build the best handling car I can have with as much comfort as possible.

[Legacy777]

For the bushings you're wanting to replace.....it really doesn't matter. Firmer the bushing the better.

The anti-sway bar bushings don't affect ride "plushness" They affect how quickly or responsive the anti-roll bars are to load shifts. With more compliant bushings, the bushings will give and the bar will shift before it starts working.

For the steering rack....pretty much the same thing holds true.

Where firmer bushings start coming into play in terms of ride quality/plushness is on the lateral links, trailing links, and A-arms.

[professor]

Well said Josh.

Polyurethane can be formulated for a high rebound (bouncy), or for excellent damping quality. Polyester usually has a little lower rebound than polyether urethanes.

But I doubt that a bushing maker pays much attention to that, the durometer (hardness) will have the biggest effect. Urethane has been indicted for two main faults: too hard, and too squeaky.

This is due to bad formulations and not any inherent weakness. The bigger faults are durability in the prescence of solvents, water, and heat.

[93Leg-c]

Thanks, Josh and Professor. I keep on learning.

So, for the steering rack and sway bushings, the firmer, the better. So, any advantage of the Whiteline over the blue bushings or vice versa in firmness, longevity, less squeakiness, etc.?

Professor, so is Whiteline's bushings the polyether urethane or polyester urethane? Since I'm in the desert, would the polyester urethane be better for longevity? Or, perhaps it doesn't matter whether the bushings are polyester or polyether urethanes since they're both urethanes?

I hope I'm not exasperating you, I'm just trying to learn.

[Legacy777]

Personally....I don't think it matters. I've used whiteline bushings and haven't gotten any squeaking at all.