You like that headline, right?
So, our E46-chassis BMW M3. Its steering never felt awesome. Let’s call it a little soft, which is a polite way of calling it vague. We could feel a bit of play in the steering before things seemed to engage.
Recently, while backing out of the garage, steering feel suddenly seemed to go from …
The moral of the story is to support the experts that know your chassis as well as specialist vendors and not just rely on random Facebookers for troubleshooting and ebay for parts of unknown origin :)
The real question is - why is there a rubber donut in the steering column? Why not replace it with something without a spring rate? I figured there were probably some aftermarket options and a quick google says I was right: poly, billet or a normal U joint. As an E46 owner, why would I want to use any of these or OE?
That is a very important moral of the story: trusted sources and trusted parts are good.
Condor Speed Shop offers a non-rubber steering U-joint replacement. As the site says, though, track use only.
Also, hope you all appreciated the headline. :)
David S. Wallens said:Also, hope you all appreciated the headline. :)
BMW mechanics hate him!
In reply to jgrewe :
I’m saving that one for another update.
Similar to a rag joint in the offroad world, where there are kits available to replace them with something solid - not something I would recommend for an offroad vehicle though, as the rag joint has a very slow and forgiving failure mode while its solid replacement may not.
Also newer cars with column-assist EPS have a wearable coupler somewhere between the EPS motor and the steering shaft that can introduce some slop when it wears out.
I'm with Keith on this one, rubber in the steering column just seems like it's inviting slack... no thanks.
It does although I also see how it’s a slow failure rate vs. an instant one.
Hopefully the new one lasts another 20 years.
But if it's not there, it won't fail.
What's the purpose? Is there a change in the angle of the steering column there? I assume not, or the billet ones wouldn't work at all. So why does BMW need a flex joint there? And it seems that steering U joints are a pretty solved problem, so why not one of those?
So many questions :)
Took some hunting, but apparently there's one in my E39 M5 as well. It's only listed on RealOEM as part of the $615 lower column, but that looks serviceable to me.
Keith Tanner said:What's the purpose? Is there a change in the angle of the steering column there? I assume not, or the billet ones wouldn't work at all. So why does BMW need a flex joint there? And it seems that steering U joints are a pretty solved problem, so why not one of those?
So many questions :)
I always wondered if its somehow a safety thing. For the column to "breakaway" at that point on a front end collision.
On the early e30, without airbag and collapsible column, that's its purpose, I think.
I noticed my e92 M3 went to a solid u-joint, so I purchased one to test when I swap my e46 M3 rack. Been waiting for a month for BMW to ship me the rack, but I will post here whether it works or not.
Maybe it reduces vibrations to the driver?
Or gives the steering column a longer service life than if the entire length were solid?
In reply to j_tso :
I can certainly see it being for isolation, but isn't that basically removing steering feel by design? Allowing the column to shear in a crash is plausible, but it's certainly not done by every automaker.
Keith Tanner said:In reply to j_tso :
I can certainly see it being for isolation, but isn't that basically removing steering feel by design? Allowing the column to shear in a crash is plausible, but it's certainly not done by every automaker.
It may not be removing feel as much as its eliminating noise in the feedback, enabling the steering feel to provide a better SNR for the driver, especially when driven on public roads.
No Time said:Keith Tanner said:In reply to j_tso :
I can certainly see it being for isolation, but isn't that basically removing steering feel by design? Allowing the column to shear in a crash is plausible, but it's certainly not done by every automaker.
It may not be removing feel as much as its eliminating noise in the feedback, enabling the steering feel to provide a better SNR for the driver, especially when driven on public roads.
This is correct. BMW is not a sports car, but a sports sedan company.
I have replaced my e36 "guibo" with an e34 solid u joint here, but then again without power steering and with massive front tires, can't feel my biceps after getting out of the paddock, let alone the road. Atleast the LS headers won't melt this one.
I ended up building my own lower steering shaft for the Jeep at one point. The original was getting worn (u-joints were a little sloppy and the rubber sleeve in the slip joint was getting loose). Couldn't find an aftermarket replacement that actually fit properly, so I just bought some double-d steering shaft and suitable u-joints and made my own. It still has the slip joint to allow the shaft to collapse in a collision, but it's a tighter fitting metal on metal joint now, so nothing should degrade in there like the rubber did.
Just chiming in to say that my E46 ZHP had probably the best steering feel of any car I've ever owned. But it was practically new. I'm sure once the guibo has some wear and tear that starts to go away. But when new, there's nothing vague about that steering system.
I always assumed that they were there for NVH.
jgrewe said:David S. Wallens said:Also, hope you all appreciated the headline. :)
BMW mechanics hate him!
Also, you will totally like the next BMW update. :)
Can the rubber actually increase performance?
Like basically smoothing out steering reverse inputs when driving near the limit?
Let's say you are near the limit of front traction and a bump or irregularly in the road inputs steering angle change forces. If you have a solid column, this could end up being similar to a 'not very smooth' steering input by the driver.
Maybe a rubber coupler smooths out those tiny little peaks allowing the car to not break traction and therefore reach a higher performance level?
In reply to Keith Tanner :
This is where I land too. I suppose if the durometer of the rubber were tuned to eliminate certain frequency vibrations, you wouldn't lose much feel, until it is past its service life. It would eliminate some less than desireable NVH.
I still don't like the idea though. On your regular E46, sure, dampen it up a little. But on an M3? Just doesn't fit the character of the car, let me feel the thing talk through my hands!
I don't think it's a shear thing though. If I recall, both my Miata and Supra have splined shaft couplings that allow a certain amount of collapse before things would bind up and become solid.
Those u-joints are a problem area, if you're getting any klunking, that's the spot. The corrugated area at the top of the steering shaft is made for it to deform in a wreck. I think the coupler is just for NVH purposes.
I know there are some delrin replacements for e30's. I've never seen one listed for an e46 though
In reply to Caperix :
Not that I’m Mr. E46, but I haven’t seen any urethane/Delrin replacements, either. The closest I have seen for the E46 is this one from Condor.
David W,
Would you post a picture of the removed steering coupler, please.
Could help those who want to inspect theirs.
Cheers, David
David W,
Would you post a picture of the removed steering coupler, please.
Could help those who want to inspect theirs.
Cheers, David
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