how much wheel bolt should go into hub?

[chris-durham]

Hello, looking for feedback from those who have fitted aftermarket wheels and spacers.

I am thinking that the wheel bolts currently fitted are not long enough. From what I can see, there is only around 10mm of bite on them...

Any comments?

Untitled by chris pollin, on Flickr

Untitled by chris pollin, on Flickr

 

[merc85]

From the web

Thread engagement length is critical. At the minimum, thread engagement length must be equal to or greater than the diameter of the fastener. In other words, if the stud is 1/2-inch in diameter, the nut must engage onto the stud by at least 1/2-inch. If not, either a longer stud or longer nut must be used. If a longer nut is needed, the nut must protrude further through the wheel hole to meet the stud.

 

[chris-durham]

to me, just looks too small.

Anyone with a CLS55 with std 19's that may have measured how much bolt bites into the hub?

 

[merc85]

Just looked at the Oe bolts from my s211, fitted with Oe wheels and the Length of the threaded part which went into the hub was exactly half the bolts threaded length.

 

[MancMike]

If you google used wheel bolts and look at images, it seems pretty universal, and the info merc85 found seems to be the case.

 

[Alex]

10mm is plenty. 7-8 turns (=mm) is the norm.

 

[Major774]

I worked on minimum 6-7 full turns when I ran a spaces and aftermarket wheels a while ago, and had no problems.

 

[kid-jensen]

.........at least, no one came back and complained!

 

[Petrol Pete]

Merc85 answered this question in his first post. End of story.

 

[KennyN]

I fitted 19`s to my CLS which required spacers and longer bolts.

The standard protrusion on the stock 18" AMG wheels is 19mm F and 20mm R , there is clearance on the discs holes so there will be that size to account for meaning the actual size that grips into threads on the hubs. So without measuring my car then i would think there will be around 14 - 15mm of used thread.

So i just fitted longer bolts that gave the same size as the original wheels once the spacers were fitted.

Too long on the rear and it can interfere with the handbrake mechanism.

The fact you are questioning the length then i would just get a set of 5mm longer ones for piece of mind for all they cost.

Remember most aftermarket wheels use a tapered bolt seat whereas the MB ones use a conical seat.

Kenny

 

[moonloops]

May sound simple but you need to add the width of the spacer to the bolt length to get it spot on.

Plenty of numpties shown on youtube where all 4 wheels and spacers have overtaken the car due to not using correct bolt lengths

 

[MancMike]

Merc85 answered this question in his first post. End of story.

Right mods, let's gerrit locked!

 

[KennyN]

Merc85 answered this question in his first post. End of story.

Not really applicable in this case as the the hubs are only about 9mm thick so having a bolt that has 14mm of usable thread (same as the dia) will stick through the hub with a few threads not doing anything, which the MB ones do.

I think the Internet search results relate more for minimum requirments for maximum strength with a blind hole.

Until the OP is satisfied with any answers given then closing the thread will only confuse matters for anyone else asking or searching for a similar questions in the future.

To recap, on my CLS there is around 14 mm of usable thread on the wheel bolts once you factor in the clearance on the disc holes, around 4mm of this will stick through the hub once fitted. If you have 10 mm then you will have maximum thread contact within the hub , but for some reason MB like a little extra so , as stated , I would go another 5mm to keep it the same as factory.

Kenny

 

[Allan AMG]

Right mods, let's gerrit locked!

Tbh I'd be inclined to the think they would be moving the thread to the general section

 

[edc]

Whatever the thickness of the spacer get a bolt which is longer than the OE bolt by the same.

 

[Doc matt]

Reminds me 20 years ago when I bought some alloys for my Renault Clio. I bought studs 10mm too long. They went all the way through the hub and scraped so loudly on the metal shield behind it.

Me and my mates were driving to Torquay that evening and we couldn't get the right sized studs so drove all the way there with noise that sounded like a thousand people hammering a tin pot.

Jesus the things you do when you're young

 

[ricky s]

Jesus the things you do when you're young

LOl. yes great days!

 

[chris-durham]

Not really applicable in this case as the the hubs are only about 9mm thick so having a bolt that has 14mm of usable thread (same as the dia) will stick through the hub with a few threads not doing anything, which the MB ones do.

I think the Internet search results relate more for minimum requirments for maximum strength with a blind hole.

Until the OP is satisfied with any answers given then closing the thread will only confuse matters for anyone else asking or searching for a similar questions in the future.

To recap, on my CLS there is around 14 mm of usable thread on the wheel bolts once you factor in the clearance on the disc holes, around 4mm of this will stick through the hub once fitted. If you have 10 mm then you will have maximum thread contact within the hub , but for some reason MB like a little extra so , as stated , I would go another 5mm to keep it the same as factory.

Kenny

Thanks Kenny, was exactly the info I was looking for. As i bought the car like this I didnt have std wheels or bolts to compare to.

cheers again.

 

[Abb]

Chris, the wheel bolt length came recommended by the wheel supplier when I purchased the wheels, whilst working out spacers, offsets, fitment details etc. I had no issues with them at all and they have been on there for at least 2 years. Would have piped up sooner, but been away from the forum for a while.