The Stovebolt Site Forums The Parking Lot Big Bolts Proper Big Bolt Wheel and Tire Sizing?

I have an Advance Design Big Bolt Cab and fenders in excellent condition BUT no frame or chassis.

I plan to build a custom truck for daily use with a utility body for everyday construction work.The body will be modified for a vintage look.

I plan to use a modern Chevy/GMC chassis,frame and running gear.It is going to be a dually.I am an experienced welder and fabricator.

Where I go from here is based on tires and wheels,believe it or not.By my eye,big bolts don't look good at all with anything less than a 36" tire.And the truck will be a dually.I want all the tires the same to be able to rotate or change them around on the road in case of a front flat.

I was wanting to go with a mid 90s chassis with 8 lug/6.5 pattern,originally.But the wheel choices are 16" and 19.5 off a Step Van.Really can't find a 36" dually tire for these wheel sizes, though.It's a shame,because the 19.5 wheel would look right,but the tallest dually tire,from what I can tell is 33 inches,too small.

A 20 inch Budd wheel would be great too.I could run a 8.25/20 and it would look good.But for some mystery,it doesn't seem to be a wheel like this in 8/6.5 lug pattern.Yes,I know there are customs out there,but thousand$ for wheels ain't in the budget.Plus,I am going with a painted wheel anyway.

So then,you go up to 22.5 wheels.I could run a 9/22.5 tire and it would look good.But as far as I know,there are no 22.5 wheels in a 8/6.5 lug pattern.I am pretty sure they are all 10 lug and can be run with a monster sized adapter that isn't cheap and weighs a ton.And then the question of whether the 22.5 wheel is just too large and not look right either.

So that's where I am at.I know that the BIG Bolt wheels are discussed all the time,but this is a little unusual because I intend to use a modern chassis and running gear.If anyone has been down this road,any advice or info is appreciated.

p.s.I haven't got the chassis yet,so even a 10 lug chassis is a possibility.

10 lug 3500HD Or a bread truck or RV P30 chassis also with 5 and 10 lug axles. They have a 7.25" bolt circle like the original AD BigBolt did.
Then you can run old 20" wheels or if you can find them 22.5". Check the pictures of my truck project with those 22.5" wheels.

One difficulty of using a later chassis is the front axle is usually much wider, be sure to use your tape measure before deciding on a chassis to use..

You'll find some more info in the disc brake sticky thread as well as in the big bolt wheels and tires tech tip.

Grigg

Going with a larger chassis with easy to get 22.5" wheels is worth looking into. Freightliner and Oshkosh step vans come to mind with large 8 lug hub piloted or 6 lug Budd.

Grigg,I knew you would come through with some great info.
I had not considered other makes like Freightliner or Oshkosh.

Yes,front end width is a concern.It does seem like the front wheels will tuck into the fender wells with a 80s or 90s Chevy 3500 chassis with Big Bolt fenders,being that they are wider than the pickup.I have measured,and it would appear that it would work.I wouldn't know for sure until I actually set the cab and fenders on a rolling chassis,of course.Plan B would be to section and widen the fenders if needed.

I would really prefer to use a 90s 3500 2wd chassis with front coils and A-frames.I'm not sure if the 3500HD chassis ever came with anything but a straight front axle.I like the A-frame chassis,it drives and handles fairly well.I also want an all chevy drive train,and can use everything else,like hydroboost and other accessories.All the Chevy parts are reasonable and easy to get.The truck will probably travel down the road at 10,000 pounds loaded for work,and also tow a 10k pound trailer when needed.

Another option,I guess,would be to get the chassis I prefer and swap in a 10 lug rear,with discs and use the 22.5 wheels on it,and use 8lug to 10 lug adapters up front.

Grigg,do you have any photos of your truck with the 22.5s and the front fenders on it? I didn't see any.

Nope, don't have the fenders on mine yet.

3500HD always had an I beam axle. I currently have a 3500HD axle under my 48 6400 but it has been narrowed about 10". You won't really fit even the big bolt fenders over that axle, its at least about 8" too wide, something like 4" of tire hanging out each side unless you narrow it or stretch fenders.
However there were step vans and RV's with independent front suspension and the 10 lug wheels (5 up front). That version sounds like what you're trying to find. I don't know if they're any narrower than the I beam axles though.

Grigg,thanks a bunch.

If you get a chance sometime,can you get an approx measurement across your front end,from outer edge of left front wheel to outer edge of right front wheel? I can check that against a 90s 3500 chassis at work.

Thank you for that great info about the step vans and RVs.If I didn't hear that from you,I wouldn't know to keep my eyes open.

Sounds like you have run into the challenges I will face soon.I have steering,steering column and pedal concerns.I'll start a thread in HiPo on that when I can figure out what my questions should be.

Width measurements can be found here.
https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=725027#Post725027

Most helpful and accurate way of noting the width of a front (or rear) axle is wheel mounting surface to wheel mounting surface, it is fixed and not dependent on variables like different rims or brands and sizes of tires.
If you want width outside of tires or rims on the front axle you can measure the offset from wheel mounting surface to outside of tire or rim and subtract it twice from the given WMS to WMS measurement.

You may be better off to swap the axles or brakes under an original frame? See the link above as well as.
http://www.stovebolt.com/techtips/bigbolts/p30swap/
and http://www.stovebolt.com/techtips/wheels/

Grigg

I have a P30 chassis with the independent front suspension, and thought it is wider than the original tire-to-tire width, the tires fit under the fenders just fine. 52 COE, by the way.

Once again Grigg, you are the man.

After digesting a lot of that great info,I am leaning toward a 90s Chevy 3500 chassis and swapping out the rear for a 10 lugger.I'm not really clear on what 22.5 wheels I would be looking for if I do.

While I have everything stripped down,I probably will modify the rear suspension.Especially now that I am probably going to run a rock hard semi tire.You have any thoughts in that direction? You can be brief,I'll post something in HiPo pretty soon in that regard.But remember,this is a work truck that will carry and pull a load daily.

Hey Brew,that is great to know.What size tires are you running?

I am building the exact same thing I went with a 80s bread van and then swapped a 5 and 10 lug suspension under it from a motor home. It was a direct bolt on and took about 3 hours to do. Any p 30 chassis with 19.5 tires will work. I am also running 8R19.5 tires on mine (still a little small).
Thanks
Brad

Brad,that sounds cool,it is great to know that other guys are in the middle of similar projects.

When I first figured out a while back that 19.5 wheels would not be a problem for the direction I wanted to go,I thought I had it licked.But all the trucks and step vans I saw in my travels all had what looked like "low profile" type tires.I figured when it came down to it,I would be able to locate taller tires for a 19.5 wheel.Now that I am serious about,and trying to button down the plan and locate everything,it seems that they are not out there.Its just a shame,would have been simple cheap and easy.

But,I can tell that Grigg has been waging war on this problem for quite some time and is ready to unleash a hornets nest of knowledge about it.

5/10 lug I assume/hope?
That's certainly good to know and sounds like the direction MrJuanderful should be looking.

Brad, you said you started with an 8 lug bread truck and swapped 5/10 lug stuff. It sure would be easier if MrJuanderful can just start with the 5/10 lug stuff. Just look for the right chassis and skip the axle swapping.

To keep the available 19.5" wheels that are usually 6" or possibly 6.75" wide 8r19.5 tire is as tall as you get. Not really any good taller options even if you had a wider wheel, not that wider would look right either.
9R22.5 tires seem to be just about the right looks and size for the AD Big Bolts. Only trouble is finding the 22.5" wheels with that bolt pattern as they came from 55-59 Chevy 1.5 tons only and many of those trucks had 20" wheels not the 22.5".

If you're set on this project the 5/10 lug independent front P-30 and 55-59 22.5" wheels sound like your best option.

Alternative is stick with the original truck chassis and swap spindles and disc brakes over to the original front axle as laid out in the disc brake conversion thread. Also swap the rear and you'd be still be looking for those 22.5" wheels.

Or same idea as the disc brake swap to old axle and chassis but with the 6 Lug Budd bolt pattern, like this project. https://picasaweb.google.com/118082002072608219229/53GMCDetroitDieselConversion453TAndRoadranger02
An Oshkosh step van would provide rear axle and front brakes.
the advantage there is 6 lug Budd 22.5" wheels are quite easy to find.

An in my opinion lesser idea would be 8 lug P30, expensive aftermarket wheel adapters and 22.5" semi truck wheels, but I think that just looks wrong, and you'd have relatively small brakes compared to the other options.

There's always the option of fixing up the original truck as it was and just driving it, that has worked for countless people for years and years.

Grigg

Grigg,again thanks for the fountain of information.

Just keep in mind I Do Not have the chassis yet.A while back I purchased a complete cab and fenders ONLY.The cab and fenders are in excellent condition as it was from a fire truck that of course was kept indoors and babied most of its life.How it became separated from its chassis and fire equipment is a mystery at this point.

So,in other words,I am wide open to any chassis choice.However,the service body I will be using will end up approximately 10 to 11 feet long when completed.You say "What?Ruin the vintage look with an ugly modern tool body?" Well I have plans to give it body modifications to both the front and rear of the service body to give it a vintage look.Yes,a lot of fabrication.My inspiration is 1940-1960 fire truck service bodies and "chariot style" wrecker bodies.I have collected hundreds of photos and have illustrations ready to build.I'll be modifying a modern aluminum body for this,the vintage stuff is generally too poor and not enough tool boxes for my needs.

I have been poking around things the last few days,taking measurements and stuff,and I really can't see not having to widen the fenders.Even if the tires would sit within the fenders,I can't see how they would not rub during real world driving conditions (on a modern chassis).

Another thought I am considering then,is if I have to cut,weld and massage these fenders,maybe I can modify the outer fender opening to make it smaller.Seems to me that the larger Big Bolt opening is what makes a 33" tire seem puny in comparison.And this truck is not going to have to be tall,like say a flat bed.Not talking a hack job here.Probably would get some donor AD pickup fenders to cut up and help with it.

If you want to run 8R19.5 tires they fit nicely in the small truck fenders, just use a complete small truck nose. The fender width is a little narrower on the small trucks than the large though.
Build yourself a 1 ton and not a 2 ton, then the smaller wheels look great.


Grigg

Yes,Greg, I guess I might go for a "tweener" or something.

But,I still need that extra fender width,and I want the longer Big Bolt hood to get as much engine compartment room as possible.My thought now is to power it with a 6.0 LS engine and a 4L80e automatic.

Engine compartment room is the same for 1/2 ton up to 2 ton trucks. The radiator is mounted in the very same spot and so is the cab. You can bolt an entire big or small truck cab and nose on the other's frame.

What is the difference in the hood sizes?

They're not interchangeable but no significant differences in hoods as far as fitting engines under them. I think (haven't measured lately) that the big bolt hood is shallower because the fenders are taller.
I don't have a real clear/good answer though.

Find yourself some GMC 400, 450, or 470 series fenders, & they will be automaticly wider.

Thanks Spanky,I knew that some of the GMCs had some larger stuff,I'll have to look into how much wider they really are.

The ones Spanky mentions are significantly wider, easy to spot just looking at the loose fender even without another near by to compare it to.

Thanks Grigg, I haven't spent enough time around ADs to spot anything on sight,Geez,that could be what I have already,I'll dig into it later.

Another question,I posted a steering question about the truck in HiPo,not sure if the highly modded Big Bolt questions belonged here.I just don't know if most of the folks in there are thinking along the lines of S-10 chassis.Let me know where I should post these high fabrication questions.

I took some rough measurements off a couple of trucks today.

The 53 GMC (GVW=16,000) was approx 72 inches between the inner lips of the two front fenders at the highest point of the fender opening.

The mid 80s Chevy 30 series was approx 74 inches from the outer sidewall to outer sidewall of the two front tires.

The mid 90s Chevy 3500 series dually was approx 74 inches from outer sidewall to outer sidewall of the two front tires.

The outside of the front fenders on the 80s and 90s Chevys were about even with the outside of the tire sidewalls.

When I leave work tomorrow I'll grab a 4 foot level so I can accurately mark and measure these items again and I will correct this post for posterity.

Yes...the topic is back,sorry.If I can get this figured out,I can finally get some sleep...ha!

The 400,450 and 470 are all COEs?

Do the COE fenders fit on a Big Bolt nose?

Would I have to lower it like this?
Red COE

(just kidding about lowering)

The 400,450 and 470 came both COE & Conventional cab.

The COE fenders are different because of the shorter nose.

Ok,i was trying to find some web pictures of those series and I was only coming up with COEs.

Check out www.oldgmctrucks.com , & you'll find some photos of 400, 450, & 470 conventionals.

Kook has one.

I have some photos of a 1950 GMC 450 conventional.

http://i894.photobucket.com/albums/ac149/eagluh1/image_zpsf706d12f.jpg
http://i894.photobucket.com/albums/ac149/eagluh1/image_zpsf2e1de91.jpg
Mine, 1950 GMC 450

Slideshow
http://s894.photobucket.com/user/eagluh1/slideshow/

Are the grills and grille surrounds the same on these trucks,or are they wider also?

Thanks for the directions to the 400 series and up and larger conventional cab fenders.I just suspect they are just so large,they would look out of place on the truck I am beginning to work on.I am still searching and looking for a way to get some additional width without growing the entire fender and spreading the distance of the headlights.A flare maybe?Some fabrication is in store,and a lot of mock-up,if there aren't any examples out there.