Torque Front Shock Tower Nut?

Bruce · Post by **Bruce** » Tue Mar 10, 2009 8:48 pm

I'm sure this question is easy for most of you, but the self locking nut on the front shock absorber - how and with what do you torque it with? I don't see how you can torque the nut and hold the shaft (hex on top) at the same time. I'm sure this has been covered before, but I'd like to make sure it's right. Right now it's on with an air gun, but I don't think it's tight enough.
Thanks!

1st 5er · Post by **1st 5er** » Tue Mar 10, 2009 11:16 pm

Bentley recommends 96 ft-lb for the "Strut Housing Threaded Collar" for the E28.
It's got to be close to the same for the E12.

YouTube · Post by **Peter Florance** » Wed Mar 11, 2009 8:57 pm

I found a sheetmetal type socket in the plumbing section of Lowes and I could put a socket through it to get to the shock rod (in my case the Bilstein rod had a hex top to it)

Bruce · Post by **Bruce** » Thu Mar 12, 2009 11:47 am

That's what I was talking about - a sheetmetal type socket. I'm off to Lowes. Thanks for your reply, my stress is reduced!

KenB · Post by **KenB** » Mon Mar 16, 2009 1:48 pm

Not to say other ways won't work perfectly well, but the "right" way to do it is to use a torque wrench that accepts inserts, such as ring spanner inserts. Then you would hold the center of the shock with the allen bit and torque the nut with the torque wrench with spanner bit. But those wrenches and bits are $$$ typically. I just use an offset ring wrench and an allen bit to get it "plenty snug" and call it a day.

KenB
1980 528i

Mike W. · Post by **Mike W.** » Mon Mar 16, 2009 8:35 pm

Even though it serves a critical function, I'd say the torque is non critical. Meaning I just give it a quick shot with the impact wrench. It's a lock nut, and as long as you don't get it so tight you shear it off, or it's so loose there is play, it's good. And with the locknut, it'll stay that way.

Adam W in MN · Post by **Adam W in MN** » Tue Mar 17, 2009 8:42 am

Mike W. wrote:Even though it serves a critical function, I'd say the torque is non critical. Meaning I just give it a quick shot with the impact wrench. It's a lock nut, and as long as you don't get it so tight you shear it off, or it's so loose there is play, it's good. And with the locknut, it'll stay that way.

Agreed, I always use an impact wrench for it. I find that tool is super useful for any situation like this where you are trying to tighten a nut and keep the shaft from spinning.

For anyone who doesn't have an air compressor, I would recommend Dewalt's electric impact wrench. It does 240 lb/ft if I recall and I use it for 90% of the work rather than firing up the air compressor. I highly recommend it.

YouTube · Post by **Peter Florance** » Tue Mar 17, 2009 8:54 am

Adam W in MN wrote:
Mike W. wrote:Even though it serves a critical function, I'd say the torque is non critical. Meaning I just give it a quick shot with the impact wrench. It's a lock nut, and as long as you don't get it so tight you shear it off, or it's so loose there is play, it's good. And with the locknut, it'll stay that way.
Agreed, I always use an impact wrench for it. I find that tool is super useful for any situation like this where you are trying to tighten a nut and keep the shaft from spinning.

For anyone who doesn't have an air compressor, I would recommend Dewalt's electric impact wrench. It does 240 lb/ft if I recall and I use it for 90% of the work rather than firing up the air compressor. I highly recommend it.

It is possible to snap off hardened shock rods like Bilstein

The impact is fine for removal but I strongly recommend against it for installation.

Mike W. · Post by **Mike W.** » Tue Mar 17, 2009 12:58 pm

It is possible to snap off hardened shock rods like Bilstein

Do I read that as you've done it? I'm surprised, I could see it more on E28's, which use a much smaller shaft/threads, but E12's are pretty beefy. Was it wailing on it for an extended time, or just a quick shot or what?

YouTube · Post by **Peter Florance** » Tue Mar 17, 2009 1:09 pm

Mike W. wrote:
It is possible to snap off hardened shock rods like Bilstein
Do I read that as you've done it? I'm surprised, I could see it more on E28's, which use a much smaller shaft/threads, but E12's are pretty beefy. Was it wailing on it for an extended time, or just a quick shot or what?

No and maybe it's a generic warning.

Remember though I had my Sports machined down to 14mm to fit camber plates.

I just think it's not a great habit to get into.

Adam W in MN · Post by **Adam W in MN** » Tue Mar 17, 2009 1:50 pm

Peter Florance wrote:
No and maybe it's a generic warning.

Remember though I had my Sports machined down to 14mm to fit camber plates.

I just think it's not a great habit to get into.

I don't sit there and wail on it for 30 seconds with the impact wrench. I'm done when the nylon lock nut starts slowing its progress considerably and mainly use it to get the nut down far without having to hold the shaft steady.

Bruce · Post by **Bruce** » Tue Mar 24, 2009 12:01 pm

Well I couldn't find a sheetmetal type socket in the plumbing section of Lowes. So I took a deep 27mm socket and machined the top 1/2' or so down to 1 1/4" hex using a Bridgeport mill and carbide end mill. It now looks like a spark plug socket. Then I used a 11mm 3/8 drive socket with a 3" extension through the 1/2" drive hole in the 27mm socket to hold the Bilstein piston rod and used a 1/2" torque wrench with a 1 1/4" open end crows foot to torque the M16 nut to 81 ft/lbs. Whew, got that out of the way!

Thanks to all who replied!!!

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Torque Front Shock Tower Nut?

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