control arm bushings...

[SharkmanBMW]

M5 or 750 bushings???

opinions please, I searched the posts, but I want up to date feedback on new users of the M5 bushing...

Winfred loves them, and I am interested but want some more feedback!

Are the M5 bushings more harsh or how do they compare?!

price is not the issue, just want the best durability and feel without being rough.

all input is welcome!

[Kalevera]

M5 durability improvement over the 750s is tantamount to the difference between the stock E34 ones and the 750 bushings.

Get the M5 ones.

best, whit

[liquidtiger720]

or try grunt bushings....look at jon k's thread.

[DueyT]

Or get Delrin inserts for the 750i bushings from Bruno (although they may be on backorder...)

[SharkmanBMW]

Or get Delrin inserts for the 750i bushings from Bruno (although they may be on backorder...)

I also wanted the delrin inserts, but I don't get replies when I contact Bruno.
So I will go M5 if they are in stock - I have an appointment thursday and they will diagnose exactly what is faulty and let me know, pretty sure they told me upper was bad.
Doing the brakes too, all 4 with zimmerman disks and Axxis or PBR "Ultimate" Ceramic pads.
I should get an alignment after plaing with control arms right??

[liquidtiger720]

No kidding, I want those delrin inserts too!

reminds me, I still have to install his subframe bushings.

[SharkmanBMW]

No kidding, I want those delrin inserts too!

reminds me, I still have to install his subframe bushings.


the subframe bushings are awesome!!! I just wish he would sell me some delrin inserts for the control arms!

[DueyT]

I also wanted the delrin inserts, but I don't get replies when I contact Bruno.
So I will go M5 if they are in stock - I have an appointment thursday and they will diagnose exactly what is faulty and let me know, pretty sure they told me upper was bad.
Doing the brakes too, all 4 with zimmerman disks and Axxis or PBR "Ultimate" Ceramic pads.
I should get an alignment after plaing with control arms right??
Chris, you might want to get an alignment after changing the control arms. I actually didn't do an alignment after changing my tie rods and centre link but I carefully measured the tie rods before installing the new ones...the car still drives showroom straight with the steeringwheel perfectly centered...I guess I just got lucky. I think I will confirm the alignment once I've replaces the CA bushings, though...don't want to push my luck. :D

Cheers,
Duey

[Russell]

They stopped a mild shimmy. However, I think (not sure) they made my ride a lot harsher especially over hard edge bumps. I even replaced the struts as I thought they were the source of the harshness. Ride did not change much after the struts. Cornering was much better, My indy also says the upper control arms ball joints are bad. Rubber boots are shot and they clank over bumps. I plan to replace the arms with 750 inserts after I do my brakes etc.

Also, the rear subframe bushings really helped make the car more stable in cornering.

Anyway, one persons observation



No kidding, I want those delrin inserts too!

reminds me, I still have to install his subframe bushings.

[Bill R.]

bmw engineers went to a lot of trouble to design the stock bushings and a fine line was walked to give you the best tradeoff in ride comfort versus handling versus durability. Anytime you stiffen up an area on the stock suspension there's going to be a tradeoff in harshness and instead of wearing out the bushings it will instead transfer the load to other components and wear them out quicker. I see this a lot with people who think they need urethane bushings, but if your willing to put up with the tradeoffs then go for it. Last week i replaced the radius arm mounts on a bronco who had put extremely stiff urethane bushings on them 6 months ago and now he actually broke out the radius arm mounts where they are riveted to the frame.... I see this a lot on trucks here with the urethane suspension components kits for handling.








They stopped a mild shimmy. However, I think (not sure) they made my ride a lot harsher especially over hard edge bumps. I even replaced the struts as I thought they were the source of the harshness. Ride did not change much after the struts. Cornering was much better, My indy also says the upper control arms ball joints are bad. Rubber boots are shot and they clank over bumps. I plan to replace the arms with 750 inserts after I do my brakes etc.

Also, the rear subframe bushings really helped make the car more stable in cornering.

Anyway, one persons observation

[Russell]

This is why I want to remove the derilin inserts. They are a great idea and seem to work very well to eliminate shimmy and stiffen up the front end. They are not for everyone. However, I suspect additional stress is being placed on other components.

As this is my commute car/daily driver, reliability AND comfort are important. :)

[Kalevera]

bmw engineers went to a lot of trouble to design the stock bushings and a fine line was walked to give you the best tradeoff in ride comfort versus handling versus durability. Anytime you stiffen up an area on the stock suspension there's going to be a tradeoff in harshness and instead of wearing out the bushings it will instead transfer the load to other components and wear them out quicker. I see this a lot with people who think they need urethane bushings, but if your willing to put up with the tradeoffs then go for it. Last week i replaced the radius arm mounts on a bronco who had put extremely stiff urethane bushings on them 6 months ago and now he actually broke out the radius arm mounts where they are riveted to the frame.... I see this a lot on trucks here with the urethane suspension components kits for handling.
I utterly agree with Bill.

A couple months back, Brett Anderson sent a link to UUC of a video hosted on our web site that showed an utterly destroyed set of urethane upper control arm bushings that had recently been installed. We changed web servers recently, and I can't remember the IP to the old one so I can post the link to that video.

Regardless, here's the UUC discussion about it...

http://www.mail-archive.com/bmwuucdigest@uucdigest.com/msg06463.html

and

http://www.mail-archive.com/bmwuucdigest@uucdigest.com/msg06465.html

Particularly:

"> An issue with "U"rethane bushings that everyone fails to take into account
> is the degradation in spring rate.
>
> Replace your control arm bushings with urethane and leave stock
> springs and
> shocks in the car and you've just done the equivalent of putting softer
> springs in your car. Yeah, there's an upgrade for ya.
>
> Urethane inserts in a stock bushing are a different thing entirely and
> shouldn't be compared with the general inability of urethane to do the job
> for which it's sold.
>
> If you have a street car, use rubber. If you have a race car, use metal.
>
> Brett Anderson
> KMS"

best, whit

[BigKriss]

I utterly agree with Bill.

A couple months back, Brett Anderson sent a link to UUC of a video hosted on our web site that showed an utterly destroyed set of urethane upper control arm bushings that had recently been installed.

the video was around a while back, what brand was it?

[Gene in NC]

OK, I buy rubber bush but what is source of m5 thrust and will Grandma accept them on her '89 525. UUC comment re 750 bush 50% greater life didn't make it for us. Orig 60k, 750 83k. Rember Grandma is the driver.

[Kalevera]

Gene -- The 750 bushing must've been improperly installed/not torqued with the suspension under load.

M5 bushings are available from Patrick, the dealer....tons of places...WorldPAC (if you have a wholesale/reseller account ;) )

best, whit

[fkong777]

just swapped out my urethane thrust bushing with a new pair of Hamburg Technic thrust arms and 750il bushing.

Ride quality is day and night difference. Urethane was so harsh that I didnt like driving the car anymore. Swapped out to the new arm/bushing. I'm loving the car again.. bought back all the luxury that I lost with Urethane bushing.

true the steering response is not as good but it is embrassing to have a harsh riding E34 when you have passenger expecting a luxury car ride.

[632 Regal]

These are NOT luxury cars, they are a "Drivers" car.

[Russell]

I do not think that BMW intended thier mid range sedan to ride like an old pickup truck. IMO, thats the way they ride with solid or near solid thrust arm bushings.


These are NOT luxury cars, they are a "Drivers" car.

[TheDuke]

750il bushings (http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&category=33583&item=7987025053&sspagename=WDVW) Will these work with 525i?

[infinity5]

Is there an online source of information about urethane stuff in general, particularly hardness, measued in.. what is it? durosomething? Shouldn't the particular stiffness of the particular urethane be more important than simply that vs Rubber? Or can they only get so soft, at which point they're still too hard to use?

[fkong777]

These are NOT luxury cars, they are a "Drivers" car.
Maybe so.. but you didnt ride in my car with the solid bushing... it was nasty...