E36 M3 steering swivel u-joint upgrade

[olemiss540]

Let alone why bump a 2 year old thread just to state an opinion or start a new debate unless there is some sort of new information available......

[aeronaut]

LOL, there's that too.

[SIIDEWAYS]

Let alone why bump a 2 year old thread just to state an opinion or start a new debate unless there is some sort of new information available......

Fair point. For more context, I had initially intended to swap the stock rubber joint with the E34 solid joint without knowing that modification was required (the filing/drilling of the shaft to make clearance for the pass-thru bolt). When I realized that it wasn't such a straightforward exchange, I did some research, including coming across this old thread. And yes, I simply stated my opinion about the potential weakening of the shaft by this modification on a rather crucial component such as steering. Was not looking to debate as we all have differing opinions, so I apologize if I came across that way.

But more importantly, what I recently learned from both the local dealer and Bimmerworld was that the rubber guibo is designed to sever/crumple in the case of an extreme front end collision to prevent the steering shaft from coming straight up and through the steering wheel/airbag into the driver. When I then asked why this particular piece was used for the E34, I was told that there were other weak points designed to crumple in that model whereas in the E36 there is no other such weak point, hence the rubber guibo. So I guess the bottom line is that I definitely won't be using the solid joint, but of course that's just me. Thanks for all the input.

[aeronaut]

Fair point. For more context, I had initially intended to swap the stock rubber joint with the E34 solid joint without knowing that modification was required (the filing/drilling of the shaft to make clearance for the pass-thru bolt). When I realized that it wasn't such a straightforward exchange, I did some research, including coming across this old thread. And yes, I simply stated my opinion about the potential weakening of the shaft by this modification on a rather crucial component such as steering. Was not looking to debate as we all have differing opinions, so I apologize if I came across that way.

But more importantly, what I recently learned from both the local dealer and Bimmerworld was that the rubber guibo is designed to sever/crumple in the case of an extreme front end collision to prevent the steering shaft from coming straight up and through the steering wheel/airbag into the driver. When I then asked why this particular piece was used for the E34, I was told that there were other weak points designed to crumple in that model whereas in the E36 there is no other such weak point, hence the rubber guibo. So I guess the bottom line is that I definitely won't be using the solid joint, but of course that's just me. Thanks for all the input.

FYI, the E36 column does have a clearly designed-in crumple section, other than the guibo. The dealer and BW are likely telling you an opinion, not facts, kinda like "folding seats are made to fold in a roll over/roof crash" which is BS.

[olemiss540]

Either way I am happy 4 ya. Rock on Sideways!

[propcar]

just figured I'd share given it's on-topic.

RaceGerman has a solid u-join option and complete steering shaft. They are using a supplier that makes these parts for Nascar. Haven't used it, but just sharing.

https://www.racegerman.com/product-p...steering-shaft

[aeronaut]

Options are good!

Honestly, these solid steering columns scare me. They lose the crumple design of the OE version (the big hollow bumpy area at the top collapses/bends in a front end collision).

I made my own, with a telescoping D-shaft. I drilled a few small holes and spot welded it, hoping that the D-shaft will brake those small welds and telescope in, in a front end smash.
I have no idea if it would work, but it made me feel better installing it.

[golgo13]

But how safe is this? You've essentially drilled off a part of the steering shaft to allow the bolt to pass through, and now it's weakened. In other words, without risking weakening the steering shaft, this E34 u-joint really doesn't work on an E36, and that's why the E36 is not listed is a compatible model for this part number.

I drilled mine without issue a few years ago. Still going strong under race-like conditions.

[jakermac]

Honestly, these solid steering columns scare me. They lose the crumple design of the OE version (the big hollow bumpy area at the top collapses/bends in a front end collision).

This one has the bumpy collapsible section:

s-l1600.jpg

WDS ORIGINALS BMW E36 RHD TURBO SLIM STEERING COLUMN PERFORMANCE DRIFT TRACK USE | eBay

[aeronaut]

Oh, I like that!...except..."May not ship to United States"

[olemiss540]

Or if you are made of money: https://vorshlag-store.com/products/...shaft-assembly

- - - Updated - - -

https://www.flamingriver.com/steerin...earings?cat=73

[cohny]

I've been running it on my track car for years now and I promise you there's no issue. A walk through the paddock at most tracks will show you the same thing.

Plus why modify the steering shaft itself? I though everyone just filed down the bolt a little so the shaft can slip past it. It's much easier to simply file it on the bench and then slip the coupler on like normal than try and drill something under the car from that angle.

[SIIDEWAYS]

I've been running it on my track car for years now and I promise you there's no issue. A walk through the paddock at most tracks will show you the same thing.

Plus why modify the steering shaft itself? I though everyone just filed down the bolt a little so the shaft can slip past it. It's much easier to simply file it on the bench and then slip the coupler on like normal than try and drill something under the car from that angle.

Oh, so you filed the bolt? It seems that others filed the splined shaft to allow the bolt to pass through. But how would filing the bolt work? You'd have to know which side you need to file based on the final position of the bolt when completely tightened? Or did you file completely around the whole circumference of the bolt based approximately on where the shaft passes?

[jakermac]

Or did you file completely around the whole circumference of the bolt based approximately on where the shaft passes?

And in turn compromise the strength of the bolt itself? I'd prefer retaining the bolt strength and taking some off the shaft!

[cohny]

Oh, so you filed the bolt? It seems that others filed the splined shaft to allow the bolt to pass through. But how would filing the bolt work? You'd have to know which side you need to file based on the final position of the bolt when completely tightened? Or did you file completely around the whole circumference of the bolt based approximately on where the shaft passes?

I think you're overthinking it. I filed just enough of the bolt away for the shaft to pass by in one spot. The bolt then doesn't turn and you tighten up the clamp by securing the nut on the other end.

And in turn compromise the strength of the bolt itself? I'd prefer retaining the bolt strength and taking some off the shaft!

Nonsense!, it's an M8 bolt used to squeeze the clamp together. A quick google search returned roughly 2120 kg max load for an 8.8 M8 bolt. There's no way it will fail in this application with a little bit of the diameter ground away.

[aeronaut]

I think you're overthinking it. I filed just enough of the bolt away for the shaft to pass by in one spot. The bolt then doesn't turn and you tighten up the clamp by securing the nut on the other end.

Nonsense!, it's an M8 bolt used to squeeze the clamp together. A quick google search returned roughly 2120 kg max load for an 8.8 M8 bolt. There's no way it will fail in this application with a little bit of the diameter ground away.

That's not the way physics works.

[cohny]

That's not the way physics works.

I am aware of how geometry, stress concentrations, etc. affect yield stress, but practically speaking I stand by the gross simplification in this instance. This bolt provides tension on that clamp. There is no sheer or bending loading etc. The bmw torque spec for an M8 bolt is 24 lbft. Do you believe this slightly modified bolt is in danger of yielding?

[aeronaut]

I have no idea. But if you grind on one side of a bolt shaft, when used, the tension forces are asymmetrical. If you were to, for example, grind one side of an M10 bolt to the thickness of an M8 bolt, IMO, it will yield long before an M8 bolt of the same rating.

You're probably fine in this situation, I don't know.

[Franky goes]

I suggest we take it easy you guys.
The bolt is not grounded off in this configuration. It is the shaft that needs to be filed ever so slightly.
I have to replace the engine in the race car and I will take a picture when I do so you can see. The amount removed on the shaft is much smaller than the relief on the rack splines from the factory.
I doubt he rubber guibo is part of the collapsible feature of the column as that is mainly achieved by the 'ribs' at the top of the shaft. That being said, any time we modify something away from stock there is a risk that needs to be managed and we all have different tolerances to risk and that is perfectly fine.
Tweak to your personal limit so you can sleep at night.
Remind me to post the picture if it's not done before April.
Take care.

[olemiss540]

Agreed Franky. Regardless, nice to have some action around here outside of the typical Aeronaut suspension threads hehe.

[aeronaut]

Oh, just wait till I ask..."what settings should I use"...

[MPWRCPE]

I suggest we take it easy you guys.
The bolt is not grounded off in this configuration. It is the shaft that needs to be filed ever so slightly.
I have to replace the engine in the race car and I will take a picture when I do so you can see. The amount removed on the shaft is much smaller than the relief on the rack splines from the factory.
I doubt he rubber guibo is part of the collapsible feature of the column as that is mainly achieved by the 'ribs' at the top of the shaft. That being said, any time we modify something away from stock there is a risk that needs to be managed and we all have different tolerances to risk and that is perfectly fine.
Tweak to your personal limit so you can sleep at night.
Remind me to post the picture if it's not done before April.
Take care.

Correct. I assembled the shaft and joint on the car, ran a drill through the bolt hole, and that was it. Easy cheesy. Years of racing can confirm, it hasn't broken yet!

[golgo13]

I think the rubber guibo is just to mitigate vibration through the steering wheel to the driver.

[SIIDEWAYS]

Ok, so y'all convinced me to put the E34 steering joint on after all. But in all honesty? I can hardly feel a difference. There is no more or less NVH, and steering feedback feels just about the same? And this is with the addition of an x-brace!

[olemiss540]

Congrats! We love to convince people to do meaningless changes to their track cars. WINNER!