The last two posts are sort of surprising.

Are you guys aware of the alloy wheel mounting device that comes in the tool kit. Before you remove the wheel you screw device into one of the top bolt holes. When you put the wheel back on you simply lift it onto this temporary stud. Put in a bolt or two and tighten finger tight. Remove the tool and put it back in the tool kit roll.

I'm sure they are available at the dealer.

Steve

My '59 ponton has lug nuts. My '83 240D has lug bolts. Somewhere in between they made the change.

Len

The answer seems obvious to me.

Alloy wheels.

How do you make the top of a stud and the nut look aesthetically pleasing?
No problem if you have steel wheels and hub caps, but Alloy Wheels change everything.

Steve

I think this is the correct answer.Can you imagine how ugly it would be any other way ? Thanks for the information on the alloy wheel tool,I was not aware of its use.Johnny

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85 300sd SOLD ,85 745i,95 740i,1972 Suburban,1938 International

My Tacoma has exposed chrome plated acorn nuts.

Does your Tacoma have steel wheels?

Steve

The reason MB, BMW Jag most Euro and many high-end Japanese cars use lug bolts is because they all use hub centric hubs and wheels, whether steel of alloy all of the load bearing surface is carried and distributed through the hub center tang and wheel bore. Studs would serve no purpose for aligning, or fixing the wheel to the hub in this type of set-up.

American cars have usually not been hub-centric but rather stud centric by design. In this set-up you carry and distribute the load through the studs themselves, not the hub center. These studs carry the full load, this is why they are pressed in, you apply load to the press fit, not the threads. A wheel bolt on a stud centric hub is a bad idea as you are applying lateral forces to threads, not safe and very prone to sheer.

Stud-centric cars are generally sloppy, mass-produced approach whereby the rotating balance of the wheel is fine up to a certain limit, usually 120-140mph, beyond this you need special attention to drivetrain balance so as to keep it from tearing itself appart.

Hub-centric designs are more performance oriented and have more precise machining. This design lends itself better to high performance, where heavy cornering and speed loads are better carried and distributed throughout the wheel hub assembly. This is why you often find Euro performance cars with this design since the 1960's, extra need for handeling and autobahn speeds.

Hope that helps

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Stable Mates:
1987 300TD 310K mi (Hans)
2008 Jeep Grand Cherokee OM642 165k mi (Benzrokee)

I don't think the studs carry any of the lateral load once the wheel is mounted. They do help center the wheel on the hub (which you don't need on your MB), but once the nuts are tight, the clamping force does all the work. Were it otherwise, you'd be breaking studs all the time.

Current one has steel. Previous one had alloy. Both used acorn nuts. The studs on the one with alloys had a narrow section that would give if you over-torqued them. If that happened, you had to change the studs.

Wes

I knew that eventually someone who actually knew the technicalities would eventually show up.

87tdwagen gets my vote. Good explanation.

Steve

My VW Vanagon has lug bolts for front wheels, lug nuts for rear wheels.

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Kent Christensen
Albuquerque
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles

MB provides that handy tool in the tool kit to line the wheels up. Works like a charm if its used.

The center of the wheel sits on the hub and supports the wheel, and the car. The lug bolts simply keep even pressure on the wheel. Must be a good system if MB uses it. Just as long as cheap spacers are not used, then the wheel goes for a ride without the car!

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2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200

They ran out of the nuts the day they were assembling your Vanagon, so they had to switch to bolts when they got to the front.

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" We have nothing to fear but the main stream media itself . . . ."- Adapted from Franklin D Roosevelt for the 21st century

OBK #55

1998 Lincoln Continental - Sold
Max 1984 300TD 285,000 miles - Sold
The Dee8gonator 1987 560SEC 196,000 miles - Sold
Orgasmatron - 2006 CLS500 90,000 miles
2002 C320 Wagon 122,000 miles
2016 AMG GTS 12,000 miles

I was not aware of this. I have owned 3 MB's and I have worked in a salvage yard as a salesman for over 5 years. Never heard of such a thing. I will have to look in my tool kit (if I have one) and see if it is in there. My first aid kit was still in my car when I bought it so maybe that is too. We will see!

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2005 Accord Hybrid (Wifes)
1995 Subaru Impreza L AWD (Snow car)
1984 GMC Sierra 1500 (Mine)
1983 300CD Best $ I ever spent. (Mine)
1984 190D (sold and glad I did)
1983 300D (sold and wished I hadn't)

Came to me in a flash. Perhaps because of less wear and tear on the threads?

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http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42