longer wheel studs?

Cowpig

new guy + questions
#1
anyone know where to find longer wheel studs?

i have a 2008 c4500 4x4, 8 lug. I put alcoa 22.5's and 10r22.5's on it, but with the rear airbags (monroe truck equipment MTE rear suspension) there is almost no clearance from the tire to the bag.

I was able to get 1/2" aluminum spacers through BORA ... but now I can't seem to find a source for 1/2" longer wheel studs ....

i'm willing to go a custom builder for these studs... can't find one of those either but then maybe I'm not looking in the right places on the internet?

thanks for any help - the rear is an alcoa aluminum wheel with the steel inner dually - doesn't leave enough extra thread on the studs to also use the 1/2" spacer
 

Cowpig

new guy + questions
#4
Looks like you need a different rim offset rather than spacers and custom studs.
it would be easier to hit a unicorn by throwing a leprechaun at it ... not a lot of wheel options and I really don't want to try for custom wheels having just shelled out thousands on these alcoa's
 
#6
Do the airbags touch the tires when they compress?
I wonder if you can get away with the tight clearance.
Maybe you can put a camera on it and drive around carefully to see if it rubs at any time.
 

Cowpig

new guy + questions
#9
what I found for an '08 c4500 8-lug was: GM p/n 88936162 (Dorman p/n 610-525). THese are M20x1.5 ... serrated ... 21mm knurl ... but 74.2mm (2.921") long

so I'm trying to find some that are 1/2" longer

I haven't found a narrower airbag, in fact the ones on it appear to be the narrowest from firestone that handle the weight. Moving them was a consideration but that steel base plate is THICK and trying to re-drill holes to move them is definitely low on my list of things to try - I think the longer studs are much more reasonable if I can find them.... or get them made
 

Cowpig

new guy + questions
#10
Do the airbags touch the tires when they compress?
I wonder if you can get away with the tight clearance.
Maybe you can put a camera on it and drive around carefully to see if it rubs at any time.
no, not so far with a couple hundred miles on it - it's possible that it's 'okay' as is (well, I'm going to try and at least center the axle as there is a little more on the driver's side than the passenger's side). I'd really like a little more breathing room though - I can see something weird happening ie; rock gets kicked up just right and tries to go through that thin gap = rapid deflation on the highway.
 
#11
https://www.dormanproducts.com/pages/products/wheel-hardware/index.aspx

At this link you'll see a pdf you can download. Or if you've got excel you're golden....
If you know the specs of your originals, you can look for same spec, just longer.

Well I just checked it out - they only have one size "M20", and that's the one you have - sorry.

Looks like you may need to go to M22, like Kenny said..

Be carefull though, as increasing length with spacers will increase the load on the studs. In my mind you need to be well under the axle weight rating before you consider lengthening the studs - maybe going to M22 will give you the increased capacity.
Bob
 
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Cowpig

new guy + questions
#12
thanks, yeah i REALLY didn't want to mess with spacers, still don't .... and I still may not. It goes to the shop either this week or next to get the kelderman front air suspension installed, and to replace some of the MTE rear suspension parts, new shocks etc. I had planned to have them put in longer studs... foolish me thinking there'd be longer studs readily available - but i'm thinking there are none available because they aren't a good idea (read: unsafe). All I could find was the one size M20 also.


I'll see what the shop says after trying to re-center the rear axle and how much space there is once it's even on both sides - but I think it'll still be about 1/4-3/8" max unfortunately. very annoying considering these alcoas are made for this truck - but apparently not for this truck with an air suspension.
 
#13
If you go to M22, plan on spending between $9-11 for each stud. When I went to Alcoa wheels, I needed a full set -- 32 of the pricey little buggers.
 

Cowpig

new guy + questions
#14
thanks - the truck goes for the front air suspension and rear repairs in a week, at that time they'll re-center the rear axle and let me know their thoughts on space tire:bags and whether or not the studs are long enough for the spacers. if not, they found a source for 'custom' lugs but to buy all 16 + 2 extras will be over $500.... sigh

truck got back-burnered though, my dog had TPLO surgery to repair his knee last night I go get him in a little bit then we begin a few months of rehab so other than keeping the suspension appointment doubt i'll get much done to it for a while. pic of what's important right now... and then one of the truck as it is for a while longer
 

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