Mazda 6 Forums banner

1 - 20 of 32 Posts

·
Registered
Joined
·
1,991 Posts
Discussion Starter #1 (Edited)
I did the Urethane mod to the front control arms of my car and all of the unwanted looseness and jiggle is gone. The front end and steering wheel now feels very taut and BMW-ish where before it was jiggly and a little sloppy.

If you buy any structural reinforcements for the front end including strut tower braces before doing this mod you are wasting your time and money. Those can't fix this issue which is far greater of an impact on the suspension geometry than chassis flex.

The best part is it only costs $30 to do, the bad part is it takes a bit of your time and energy to do it. Here is the how to http://forum.mazda6club.com/engine-suspension-drivetrain/376713-diy-firm-up-front-suspension-front-control-arm-urethane-mod.html

Mazda was trying to accomplish 2 things with the 4 front control arm bushing holes seen in the first photo. Enhance softness of the ride, and provide capability for passive steering depending on throttle or braking application. So you can tailor what you want to keep or get rid of depending on what you fill with Urethane.

Pesronally I don't think the mazda engineers had the 30lb 19" wheels in mind when they tailored these bushings because they shake and jiggle over bumps which transmits through the steering wheel in a really cheap feeling way.

On the backside I filled all four, and on the front side I did not fill the outboard/turn in hole, so I could retain a little bit of passive turn in with throttle application, and my car has more power than stock anyways.

The car feels fabulous now, and the increase in NVH is the slightest bit more bump compression coming through the chassis, which isn't bad. Actually I can now say the front end response/solidity over bumps now matches the way the rear end has always been; it's thump-thump, instead of jiggle-thump. Off throttle mid turn now does not require an extra bit of steering input to correct for the geometry change with the passive bushings, so control is much improved. Also I currently have brakes that pulsate pretty bad, but now they shake witha much smaller amplitude. Finally, amplitude of axle hop during hard acceleration has been cut in half.

I love it. Highly recommended. And if you are feeling even more cheap and adventurous you can use the remaining Urethane for the rear motor mount instead of buying a Polyurethane one. I'll post a thread on that one later.
 

Attachments

·
Registered
Joined
·
54 Posts
Solar do you mind posting where I can get these urethane bushings? Not sure if I missed an earlier thread where you listed them
 

·
Registered
Joined
·
1,991 Posts
Discussion Starter #3

·
Registered
Joined
·
1,991 Posts
Discussion Starter #5 (Edited)
It's window adhesive; the stuff you'd use if you were mounting a windshield.
It's surprisingly pliable after curing. Likely in the 40-50 durometer range, and I'd estimate the factory rubber as in the 50-60 range, probably closer to 60. So it isn't like you are filling the holes with something rigid. For reference, Polyurethane aftermarket bushings tend to be in the 70 or 80 durometer range and without any holes.

The car feels very much oem after the change, like it should have been this way from the factory.
 

·
Registered
Joined
·
324 Posts
i was doing this to my engine mount on my drag car instead of bying new engine mount , but i was using pieces of radiator hose to fill the place where there was more place to fill and put the urethane after
 

·
Registered
Joined
·
3,080 Posts
I've thought about doing this for a while but since it's basically a "once you do it, you're stuck with it unless you want to R&R those bushings" I was waiting for more feedback from others, since if it increased NVH materially I'd probably not like it.
 

·
Registered
Joined
·
1,991 Posts
Discussion Starter #8 (Edited)
i was doing this to my engine mount on my drag car instead of bying new engine mount , but i was using pieces of radiator hose to fill the place where there was more place to fill and put the urethane after
I embedded 8 pennies in the open spaces of the engine mount with the urethane around them. I can't recommend it to anybody since the increase in NVH is equal to the benefit in functional stiffness, where as this control arm mod seems to provide an order of magnitude improvement over the very small increase in unwanted NVH.
 

·
Registered
Joined
·
462 Posts
I've done this mod to all my prior cars. I will add one thing though, if you do this do it with the suspension unloaded!!!!
Take the vehicle weight off the bushing!!
 

·
Registered
Joined
·
1,991 Posts
Discussion Starter #11 (Edited)
I've done this mod to all my prior cars. I will add one thing though, if you do this do it with the suspension unloaded!!!!
Take the vehicle weight off the bushing!!
Yep that's in the DIY thread linked in the OP.

BTW I have you to thank for turning me on to this mod originally, I just finally got around to it and love it.
 

·
Registered
Joined
·
5,733 Posts
We used to use Window Weld to fill engine mounts back in the 90's before AWR came out and started offering actual aftermarket options. The stuff worked awesome as long as the correct prep work was done. Otherwise it would separate after awhile.
 

·
Registered
Joined
·
92 Posts
Thank you solar for this great write up.

You made me think of this issue and you brought up two questions to mind. Will your idea be reliable in the long run? what if I decide to pick up aftermarket control arms like Mevotech?

The car's driving is not satisfying, as you mentioned, I feel the looseness on bumpy or rough roads.
 

·
Registered
Joined
·
462 Posts
Thank you solar for this great write up.

You made me think of this issue and you brought up two questions to mind. Will your idea be reliable in the long run? what if I decide to pick up aftermarket control arms like Mevotech?

The car's driving is not satisfying, as you mentioned, I feel the looseness on bumpy or rough roads.
If you properly prepare the bushing before this mod it will last the life of the bushing, Aftermarket arms (Moog, Mevotech, ect) could all use this modification.
 

·
Registered
Joined
·
44 Posts
I just completed this mod. The car is still on the jackstands curing. I filled the holes on the backside quite well but did not attempt the front side since the control arm is in the way. I'm curious how anyone completed the front side successfully and has anyone just done the backside?
 

·
Registered
Joined
·
1,991 Posts
Discussion Starter #17
I did the front sides too. The 3m stuff has a long stem which pokes past the control arm. It isn't easy, but it is doable.

BTW I'm still loving this mod. Everything is better and more natural now. No more steering wheel jiggle
 

·
Premium Member
Joined
·
1,077 Posts
I just completed this mod. The car is still on the jackstands curing. I filled the holes on the backside quite well but did not attempt the front side since the control arm is in the way. I'm curious how anyone completed the front side successfully and has anyone just done the backside?
Just wondering how you liked this. Did you get the front side done? Results?
 

·
Registered
Joined
·
277 Posts
Ive heard Honda guys doing this. Seems intetesting. I like my quiet ride. I had a JBR dogbone mount 80dura and the whole car buzzed but thats tge trade off. This doesnt sound terrible.
 
1 - 20 of 32 Posts
Top