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Sun Jan 08, 2006 11:25 pm

I've heard two different stories on these. A number of times I've read on this forum of the need to replace these with like kind sheer bolts for crash safety. Last summer when I was changing the heater core in a 97 passat, I talked to the ancient parts guy at the local VW who told me that the tops on those sheer off when torqued at the factory and are not crash safety parts. He told me they, the dealer techs, replace these with regular 8 mm bolts. Bentley says to use sheer bolts in the vanagon but they don't give the seven warnings on safety I'd expect for a crash part. Just wondering what you all think.

Mon Jan 09, 2006 12:10 am

Basic rule of VW: Don't do anything you do not have to.

Translation: The bolts are there for a reason.

Why mess around with something we do not understand?

Mon Jan 09, 2006 8:09 am

I still say they aren't safety related, but are there to prevent unauthorized removal of the steering lock. If not unauthorized, at least cause enough difficulty that a quick car thief wouldn't bother removing them.

I see the collapsable part at the bottom of the column as the safety feature. It will fold/separate/break, or move out of the way in a head-on crash.

I've replaced similar bots on a Spitfire with standard 8mm bolts.

Mon Jan 09, 2006 8:47 am

Collapsable steering wheels have been a safety feature in cars since the fifties. people had a habit of getting "speared" by the steering column.
The vanagon is built ridgid, or has no crumple zones to absorb impact.
The steering wheel will absorb the impact in a head on colision, the wheel has a harder time collasping without the shear bolts. Play with fire if you want to, I won't do it over four dollars in bolts.
http://www.vanagon.com/info/safety/

Mon Jan 09, 2006 10:01 am

Based on looking at a new sheer bolt and one installed, it looks to me like the part that sheers off is long in the trash by the time of a wreck. I say the top sheers during install to indicate correct torque has been achieved. The working part of the bolt is just that, a bolt.

Mon Jan 09, 2006 10:54 am

spitsnrovers wrote: I've replaced similar bots on a Spitfire with standard 8mm bolts. What happened in an accident with those bolts?

Mon Jan 09, 2006 10:56 am

mightyart wrote: Play with fire if you want to, I won't do it over four dollars in bolts.
http://www.vanagon.com/info/safety/
I agree. It simply is not worth it, to me.

I do not want my grave stone to say:

Died because he was too cheap.

Mon Jan 09, 2006 3:31 pm

OK.... those sheer bolts have nothing to do with an impact.... I have personally replaced many sets of them. The part that "sheers" is no longer there... It sheared off when enough torque was applied. If you were to remove the ones in your van, they would look just like regular bolts with no place to put a wrench. As stated earler, they are simply an anti theft device. There will be no problem replacing them with a standard bolt.. There is a mushroom looking head that snaps off when you install them.... That is the shear they are talking about...... NOT A SAFETY ISSUE>>>> :twisted:

Mon Jan 09, 2006 4:46 pm

Yes they are. most steering colums use sheer pins, these use shear bolts.
why would they even bother to put them in in the first place? they are made to break when a certain force is applied, unlike regular bolts.
the reason the tops shear off when you are putting them in is so you don't over torque the bolts themselves and break them or worse crack them making the steering colum less stable.

Mon Jan 09, 2006 8:05 pm

Eric is right on this one, they 'shear' during installation. They are also known as 'tamper proof fasteners' - as if ANYTHING is really tamper proof. :D
If in fact these fasteners were to shear off during an impact, the column and wheel would be driven down and backward into the driver's torso. Instead, what actually happens is the bolts keep the column connected to the brace, allowing the bottom end of the column to move aft as the front end of the car compresses. This creates a fulcrum point causing the steering wheel end of the assembly to be driven forward toward the windshield, AWAY from the driver's torso. The collapsible section of the column insures this happens by minimizing the load on those fasteners and the brace they connect to. Volvo, BMW, Mercedes, Chevrolet and many other manufacturers adopted this method of controlling the movement of the steering column in the 60's and it has been proven time and again to work exactly as designed. You can replace those bolts with any type of head you like, but it is best to use a grade 8 in steel, or 304 alloy if using stainless.
Here's a fun impact sequence of a Vanagon killing a 'safe' Volvo 740 wagon at a combined speed 65. Kick me if you've all seen these. .
The Vanagon CT dummy lives to crash another day, the Volvo CT dummy would have been disabled for life if he survived at all.
. . . and the 'shear' bolts DIDN'T SHEER :D :D

The setup:

The impact - awesome energy here, notice the van is airborne during the sudden stop, and the Volvo 'submarines'

Vanagon door still latched, steering wheel position almost in original position, slightly pushed forward as intended.

Volvo - things are not so pretty here . . . :D The entire dash and column are driven into the driver's torso, door is ripped open, crushing limbs.

Vanagon's load bearing structure:

More armor:

Vanagons aren't your granddad's death trap Combi anymore.

Looking at these images again, I also see VW finally perfected the 'breakaway' windshield. In 68 or 69 the bugs got an early version of this design. The problem was that simply slamming on the brakes to avoid the neighbor's cat would launch the windshield. A recall added some retaining clips as a patch until the following year model solved the problem . . Really now, as if the windshield was any danger to occupants of a bug during a frontal impact. I should think there were more serious issues to consider . .

Tue Jan 10, 2006 6:12 am

They are anti-theft bolts.Drill them out.

Tue Jan 10, 2006 7:13 am

How whould removing these two bolts make it easier to steal?
by making it impossible to drive?

Tue Jan 10, 2006 8:10 am

Ok which shear bolts are you talking about the ones on the key switch, or the ones that hold the steering wheel to the dash?

Tue Jan 10, 2006 8:37 am

So, does anyone have a picture of the lower section of that van in the crash? Where the legs are, right in front of the wheel well? I do recognize that the Vanagon driver would probably survive and that the Volvo driver is toast but, I'll bet the driver's going to need several surgeries to piece his legs back together. Ouch !! I love that picture of the windshield being airborne about 3 feet ahead of the van.

I too am curious about the "anti-theft" comments in this thread. The only thing that I can see being theft-proofed would be the steering column itself. Darned hard to remove that steering column when the bolts don't have heads. I'd be just a little more worried about somebody stealing my stereo. :wink:

Tue Jan 10, 2006 8:54 am

The shear bolts that hold the steering lock to the column are anti-theft if you have a newer vanagon you may have these, my 81 does not.
The two that hold the column to the dash are true sheer bolts do not replace them with regular bolts. you may not collapse the column with your seat belt on, but in the late seventies when this was designed most people didn't wear them.

http://www.vanagon.com/info/safety/
http://www.vanagon.com/info/safety/volvo-crash/index.html

Tue Jan 10, 2006 10:03 am

I'm takin' the torque theory/security side here. In all those pics I see no sheared off colums. And if they were, where would the steering wheel now be...into the driver! The only place for the colum to go us straight up or back, if thats the way VW intended, than I'm going out to the vanagon and drilling those suckers out! I want that wheel to stay exactly where it is and let the bottom part do the collapsing. I'd rather have shattered legs than a steering wheel through my torso, but thats just me :D

Tue Jan 10, 2006 10:28 am

And how does just the bottom part collapse?

Tue Jan 10, 2006 4:30 pm

First I would like to note for the record my post above noted these are 'tamper proof' fasteners. Others have given opinions as to why these tamper proof fasters have been used to attach the column to the car, and these seem like plausible explanations. Another explanation I was once given by a family member who spent his working life as an engineer at GM was the issue of liability. Many people who do their own repairs or add accessories are tempted to lower or remove a steering column for access to the underside of the dash. Examples might be routing wiring for stereos, CB's, etc. Since these fasteners not only dissuade the casual do-it-yourselfers from removing the column and possibly not reinstalling and re-torquing this critical safety assembly correctly, but are also not available at your local hardware or auto parts store, there is little chance an accident investigation could point to an error or failure on the part of the manufacturer if it is found the column failed to perform as designed. In other words, if these bolts had been messed with after their original assembly, it'll be pretty obvious and the manufacturer will be off the hook.

As for them ever sheering off, let me just say that a long time friend of our family owns one of the most successful automotive towing outfits in the United Stated. Since I was a kid, I've been looking at wrecked cars in three city impound yards he owns. I've seen more bloody hair in broken windshields, broken off teeth in dashboards and bloody shoes wedged between floors and accelerator pedals than most folks. I've seen really weird things like the driver's seat of a 911 with 8 bullet holes in it, but not a speck of the murder victims blood anywhere. Or a Mercedes sedan that rolled 6-7 times at over 100 miles per hour with not an inch of glass left in tact and every inch of the body mangled, but the 4 doors still opened and closed correctly. Or another Mercedes that drove off a seawall into the bay that had a live octopus in it when it got to the yard! And for you older Honda owners - you could always tell when one was mildly rear-ended - enough to break light lenses - you could tell If there was just a driver or passenger as well. Every single one of them had a failure of the seatback tilt/retractor mechanism with only a minor impact – This includes all Civic & Preludes. Shame on you Honda! On the other hand I have NEVER, EVER seen the 'sheer' bolts holding a steering column to the support break, strip, sheer, or bend - even in the multiple fatality cars that are too gross to describe. I also used to go and watch the set-up impacts that took place at a local accident investigation facility in Costa Mesa. This was the first such private facility of it's kind in the US. The place was next door to Hadley Enterprises, creator of the ‘Veep’. A Willis jeep kit for the T1 VW chassis, and less than a mile from where Bruce Meyers fabed his first dune buggy. It's clientele was a who's who of auto manufacturers and insurers seeking an independent analysis of particular collision events they faced costly litigation over. Again, I saw some amazing things but never a failure of those bolts. So I will close by saying if those bolts were designed to 'sheer' in an accident, they not only don't work in this way, but it is a damn good thing they don't.
In the interest of fact over hearsay though, I encourage anyone who finds it tough to let go of their ideas to the contrary to do a bit of home destructive testing of these bolts to satisfy their skepticism. That's what I would do, anyway. A common 10k# shop press and load cell should tell you all you need to know. You'll find their properties are just like any common bolt grade 8 or lesser.

PS for Psych-Illogical:
Yea, judging from the design of things below the Vanagon's dash, the VW's crash test dummy would have at least suffered a few rasberries and bruises below the knees even if the compartment cell stayed in tact - which would be hard to beleive at that speed. Just for fun, we should try to find more crash pictures to see how things work out in the real world.
Have a good one guys! :lol:

Tue Jan 10, 2006 7:24 pm

Thank you Phil G, I feel vindicated in my earlier statement.

Tue Jan 10, 2006 7:46 pm

Or of course you could just spend the 6.00 and put the correct bolts in and not worry about it.
http://www.busdepot.com/details.jsp?partnumber=211415549B
This is one I will argue since it is a safety issue, and I'd hate to see someone injured over bad information they got here.
the ones that go from the column to the dash are sheer bolts.
Your van, your guts.