Thrust arm bushings: Urethane vs. 750i?

[mancini_mark]

Hey everyone,

It's time to re-do my thrust arm bushings. Last time I went with lemforders with 750i bushings from BMA. Not bad. But they lasted about 60,000 kilometres. I think that's a bit early?

Anyways, I was thinking of going with either Bavauto or BMP units with urethane bushings. Bavauto say they softened theirs. Not really an issue for me. Also, I searched the archives and saw some talk about M5 bushings. Not sure what the deal with those is.

I guess the issues for me are outright performance and longevity. Which would you guys go with and why? Any experience with BMP vs. Bavauto bushings (I want the bushings already pressed for me)?

Thanks,

Mark

[632 Regal]

I did the M/5 bushings, they are more of a solid design vs the flimsy 750 bushings. I am impressed with them, I can blow out a 750 bushing on the first test drive.

[BigKriss]

m5 bush = stronger than 750i ones. If you want the bushings pressed in already, its very hard to get that in urethane unless you get some powerflex bushes. you can get the m5 ones already pressed in but you need to buy the control arm also. You want "outright performance", there are steel bushes also. They are cool :p

[Jon K]

I have urethane bushings by Grunt Bushings. Couldn't be happier.

[shogun]

http://www.powerflex.co.uk/
http://www.powerflex.co.uk/faq.asp

How much do they cost?
Typically about 5 to 8 times the cost of a standard rubber bush. However that is not the whole story. When you consider the cost of fitting new bushes and the fact that POWERFLEX will be the last bushes you every fit to your car things start to look a bit better. Then consider tyre wear, a real cost saving here. Car manufacturers have a habit of not supplying the bushes on their own, only supplying them complete with suspension arms. Paying £70 for an arm when a POWERFLEX bush might cost £15 is not a good idea. And finally as cars get older manufacturers stop supplying certain parts. Imagine your car was off the road because of a bush failure. You go to the parts shop and the part is "no longer serviced"! POWERFLEX makes a lot of sense then.

Are they easy to fit?
We design all the bushes so that they can be fitted without special tools. However sometimes it is a lot harder to remove the old bushes than fit the new ones. If you feel you have very little mechanical knowledge, experience, talent or tools, either ask a friend or get them professionally fitted.

[mancini_mark]

Yes...I heard that urethane are supposed to be a "permanent" fix. Well, at least they should last me a while.

With 60,000 on the lemforders with 750's, I figured I should do the arms and bushings. Plus, it would save me a trip to the shop to get the busings pressed in. In the interest of time, I was hoping to just bolt 'em up as a unit.

Anybody know who makes the busings for BMP and Bavauto? Don't suppose grunt sells their bushings pre-pressed in lemforder arms?

Mark

[Jehu]

I had heard Poly Bushings were uber hard and created an unpleasant ride... whats up with that?

[RallyD]

unpleasant is a matter of personal taste.
I prefer a crisp ride that some may say is bone jarring.

my pt is full poly except for front lower control arms (metal) a whopping 1.5" suspension travel on coilovers. Most would find it to be absolutely unacceptable but I was driving it daily until I got my 5.

[JMI]

I did the M/5 bushings, they are more of a solid design vs the flimsy 750 bushings. I am impressed with them, I can blow out a 750 bushing on the first test drive.
So where can i get these M5 bushings and can they be had already pressed into Lemforder thrust ams?

Thanks

Jim

[Jon K]

Honestly guys, M5 bushings are a waste of time. Go stock or go urethane. And I vote the latter. Urethane bushings are NOT as harsh as people make them seem. Honestly cannot tell the difference between my 525 (urethane) and sisters 530i (750)

[BigKriss]

Why are they a waste of time?, they seem to be common on here.


Honestly guys, M5 bushings are a waste of time. Go stock or go urethane. And I vote the latter. Urethane bushings are NOT as harsh as people make them seem. Honestly cannot tell the difference between my 525 (urethane) and sisters 530i (750)

[Jon K]

Why are they a waste of time?, they seem to be common on here.

They are common on here - they are commonly replaced ;) I drive the pants off my car and it's been about 70k miles on the urethane bushings and I haven't had a single issue. Have the lift, and check the car out routinely, bushings are golden still.

[winfred]

so i've been ****ing off installing m5 bushings for the last 7 odd years at my shop, since me and the manager found out that the m5 came with different bushings and decided to try them, i've not had one m5 bushing fail in all of that time (had a few arms wear out but the bushings were intact) but just about every blue (525 535) /white (735) / green (740 750) bushing we installed came back sometimes in less then a month, i don't even install 750 bushings on 750s


Honestly guys, M5 bushings are a waste of time. Go stock or go urethane. And I vote the latter. Urethane bushings are NOT as harsh as people make them seem. Honestly cannot tell the difference between my 525 (urethane) and sisters 530i (750)

[Jon K]

so i've been ****ing off installing m5 bushings for the last 7 odd years at my shop, since me and the manager found out that the m5 came with different bushings and decided to try them, i've not had one m5 bushing fail in all of that time (had a few arms wear out but the bushings were intact) but just about every blue (525 535) /white (735) / green (740 750) bushing we installed came back sometimes in less then a month, i don't even install 750 bushings on 750s

Meh you know what I mean - the M5 are may be the best OEM can supply, but I'll still put urethane in every E34 I own from here on out. I cannot tell the difference between urethane and 750 in stiffness.

[Anton CH.]

I am sure there is a good reason why BMW decided not to go with Urethane bushings. On a daily driver especially you want something that won't transmit noise through the chassis. If the M5 ones are good enough for the job, then why not stick with them?

Where did you get your bushings? Can't seem to find a link.

[Jon K]

I am sure there is a good reason why BMW decided not to go with Urethane bushings. On a daily driver especially you want something that won't transmit noise through the chassis. If the M5 ones are good enough for the job, then why not stick with them?

Where did you get your bushings? Can't seem to find a link.

It is an absolute fact that rubber with ride nicer than urethane in a stock car. But I only have the urethane bushing in the troublesome locations, and have no issue.

I get them from:

http://www.gruntsbushings.com/

[mancini_mark]

Hey Jon,

I think I want grunts (sorry M5ers). You sold me. My car isn't a daily driver anymore. If I want plush, I have my truck. Any issues ordering from Australia? I saw they have a North American distributor, but it looks easier to deal direct.

Mark

[BigKriss]

They are noltec brand.

http://www.noltecsuspension.com/search.php?selBrand=15&product_vhcid=83&submit=Search#


Hey Jon,

I think I want grunts (sorry M5ers). You sold me. My car isn't a daily driver anymore. If I want plush, I have my truck. Any issues ordering from Australia? I saw they have a North American distributor, but it looks easier to deal direct.

Mark

[genphreak]

I got the Grunts ones from Heasmans in Tempe, they fitted them for me too. They weren't that much- but I believe the Noltec are slightly softer (but perhaps they are the same press- apparently the Grunties are made here (or were) but were only ever sold direct via the www.gruntsbushings.com website. I like the Grunties, but they are crisper. I worry about the poor steering box, perhaps that is why the engineers went to so much trouble to fit dodgy bushings that break on first use. Seriosuly, I used stock green ones and they were broken within 1 month. I'd go M5 personally since they work and are softer, but Noltecs are a close second and are perhaps a safer bet, especially since the arms need to be re-installed carefully. :) Nick

[mancini_mark]

Sorry, I'm confused. Whose are Noltecs? Not the same as Grunts?

Mark

[Brandon J]

Mark. You did a great job of telling us your purpose for the bushings. Yes, if you do not plan on driving your car as a daily driver then you should look into the urethane bushings. What other suspension bits did you upgrade or plan on upgrading?

I use M5 bushings because my e34 is a high performance street car. Not a track car. So, I do like the little give of hard rubber. Plus, after I install it, it is maintenance free. No lube. The M5 bushings are solid and strong. I drive on a lot of potholes and take a lot of turns and brake hard as h*ll. Plus, I would rather change a thrust arm bushing which absorb some impact (thrust) rather than change worn tie rods ends, strut mounts, balljoints/arms, or bearing hubs. These bushings are lasting even in my e34 with 330+ horsepower, 7500rpm (changed chip), and M5 brakes.

Now, if I were using R-compound tires all the time, then I would look into urethane busihings and rod-end type sway bar links. I would also want to balance the different suspension components so they all work well together.




Hey Jon,

I think I want grunts (sorry M5ers). You sold me. My car isn't a daily driver anymore. If I want plush, I have my truck. Any issues ordering from Australia? I saw they have a North American distributor, but it looks easier to deal direct.

Mark

[Anton CH.]

Any squeaks with the Grunts?

[BigKriss]

i thought they were the same


Sorry, I'm confused. Whose are Noltecs? Not the same as Grunts?

Mark

[mancini_mark]

Hey Brandon,

I've already got the Sachs kit on the car. It's running on 17" wheels with 235/45's all around. I'm looking at RD sways. I'm a sucker for razor sharp response. I only drive it in the summer now, and only a couple of days a week at that. I'd love to do some autocrossing or track time. It needs a touch more power, so I'm saving up for either a turbo or SC kit. I like the idea of SC becuase I've got beautiful RD headers on that I don't want to part with.

Mark