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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | does anyone know where to get wheel adapters from 8-6.5 to the larger 10 bolt used on the 1.5 ton trucks(the front was five lug-rear was 10 bolt/ | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | Sounds like you're asking about 10 lug on 7.25" circle? Or 10 lug on 8.75" circle? | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | What year and model truck are you dealing with?
The front axle used on some 1-1/2 ton trucks is the same as that used on 3/4- and 1-ton trucks. You may be able to swap hubs and brakes to achieve what you are after. And that would be a better and safer solution than using adapters.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more... It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | 10 lug 7.25 on a 1970 c-30 | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | or the bigger circle.I can get 4 rims with new goodyears from a 1970 c-40 or 50 truck.thought they would look cool on her. | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | I think the odds of finding hubs and rear drums from that truck are nill at best.I only want to swap the rear not the front. | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | For that matter swap the whole axle, it'll be as cheap or cheaper than having adapters made. It'll come with disc brakes. If you get a Dana 70HD you've got gears from 3.54 and slower. If you find a Dana 80 you've got choices from 3.31 and slower.
Grigg | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | around here,trying to find a c-40,50 rear end is impossible.2the rear end from a 3500hd is around 12-1400$just for a reae.then I would have to get a driveshaft made up,swap the whole brake system over since that is a disc brake rear.then have emergency brake cables made.the whole swap is around 1900$.much cheaper to go with adapters.If i found a c-40 or 50 rear ,that is wider than the truck so the body we just spent 4500$ to have fabbed up is useless.we need adapters! | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | dana 70 or 80 do not have that pattern .I think?the rear in our 1996 dodge 3500 with a cummins and 4wd has a dana 80 in the rear and that has the 8-6.5 bolt pattern.the rear in my 2006 dodge crew cab ,cummins 4wd is also a dana 80 and that has the bigger hub and 8-6.5 bolt pattern.the rear in our 3500 hd chevy has 10bolt pattern dana 80different axle ends than the dodge but is also a different pattern than the c-40 or 50 rear.I think if I found a 22.5 rim with the 7.25 bolt pattern,we could weld up the holes and drill new ones.with the bigger pattern,we could bulid an adapter. | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | oh and we want to keep our 6.17"s in the rear.we just had a posi unit bulit just for this truck....786$by dteroit locker. | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | I'm thoroughly confused then, can't figure out what you're trying to do..
If you do want a Dana axle with disc brakes and 10 lug on 7.25" circle they do exist, just like your 80 in the 3500HD, and my 70HD from a P-30 chassis. I'm sure you can get one cheaper than you estimate. But sounds like you don't want one?
Not sure I understand the point of welding and re-drilling the pattern on the elusive 22.5" 10 lug on 7.25" circle wheel?
If you know what you need but it is just "impossible" to find in your area take a drive, you can get a long way from home and back again in just a day. I've yet to give up on finding and retrieving a part (that does actualy exist) seems most always what I need can be found at a price I like even after factoring in travel time. It may take some searching, but I'm pretty sure that if you really want something it's out there to be had for a deal that suits you.
What's the goal in all this?
Grigg
Last edited by Grigg; 01/01/2010 6:45 PM.
| | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | none of the wrecking yards here have any of the old stuff laying around.when the price of scrap hit 12$a lb for it everyone threw away stuff especially the old trucks from 1952-88 0r 89.so most of the rears and other stuff like rims and wheels all went to the scrap yard.the second thing in our rules for the 2010 deason,we have to run 20" or bigger rim in the rear.they think that by doing this this will slow the trucks down a lot.we are doing 300ft in a 6700lb truck in about 4.23secs.with 5 men standing on the back.with 8r19.5 recaps(height rule in tires)we are spining these tires at least 150 or so ft to they grab.So by running a taller rim and tire they(the rules committe) thinks it will slow down the trucks and make it safer.plus we just put a cpuple grand in this rear and really do not want to change it. | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | So this discussion is about a truck used in tractor pull events?
What rear does it have under it now? The factory rear should have been either the HO72 Eaton or maybe a Dana 60. I don't recall ever hearing about a 6.17 available for the Eaton and I don't pay much attention to the Dana options.
Its possible the existing rear can be refit with hubs that will fit the wheels you want. That would be stronger and possibly cheaper than having adapters made.
And since many of the adapters on the market are designed to mount big wheels for looks, I'm not sure I'd trust them in this kind of high stress application.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more... It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | this truck is NOT used in tractor pulling eventsit is used infire dept drill team events(go on you tube and look up fire dept drill team and look up events for b rigs.).this truck was a factory 6.17 ratio truck(option code R-90;18"wheels,6.17 ratio and extreme duty suspension)1970 chevrolet. | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | this truck is NOT used in tractor pulling eventsit is used infire dept drill team events(go on you tube and look up fire dept drill team and look up events for b rigs.).this truck was a factory 6.17 ratio truck(option code R-90;18"wheels,6.17 ratio and extreme duty suspension)1970 chevrolet.the rear is ho72.the front pumpkin come out and the rear cover unbolts. | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | Well I don't know anything about fire dept drill team events or the rules associated with them.
You haven't answered my question regarding who made that rear axle you have. Google searching for C-30 and R-90 doesn't come up with anything on the first couple of pages.
The rears that you would expect to find under a '70 C30 are either an Eaton HO72 or a Dana. Which of those is this, or if it's not one of those, what is it?
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more... It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | if you check with the last paragraph above yours i said it was a Ho72 rear.the rear is a GM unit.if you check with the factory chevrolet options book,on 30 series truck,page 189 middle of page......R_90 option 18"tires and wheels,heavy suspension and 350 -4brl carb.4spd tranmission and brake warning lite delete(?) truck.6.17 only gear ratio avaible for this truck.only option was a turbo 400 tranny. there was a option R_99 whish is exact same truck but with 19.5 wheels.And it is raced every week end and does not brake the rear.other depts are runnig a dana 80 and braking the axles. | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | You did say its a HO72, I must have missed that.
But I'm still skeptical that its a HO72 with 6.17 gears. I've never heard of a 6.17 available for the HO72 though it is a ratio offered in the Dana 60 which was offered in '70. Can you post a picture of your axle?
I don't have a copy of the options book you refer to is that book available online somewhere? If so can you post a link to it?
But we're getting away from my purpose in identifying the rear. If it is a Dana there may be a 10-lug hub available that can be adapted to it. That would make running the wheels you want a simple operation.
If it is an HO72 it probably has 1/2-inch lugs that are a little small to start with. Adding an adapter is going to put more stress on them and make breakage more likely. I know you are very committed to your existing axle, but if its an HO72 the smart move may be an axle swap.
Although having said that, I do know that there is some interchangeability between the HO72 and its successor, the GM 14-bolt. I don't know if that includes hubs, but since 10-lug hubs are available for the 14-bolt it might be worth investigating.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more... It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | ...but since 10-lug hubs are available for the 14-bolt it might be worth investigating. I'm unaware of this. Excluding the 1.5 and 2 ton axles from the 50's and back with drum brakes. The only axles I know of now with the 10 lug on 7.25" circle are Dana 70HD, Dana 80, and one model of a Rockwell (square tube axle). These are all axles available in either a 3500HD or a P-30 chassis. Grigg | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | no,go back to 1967.You could of bought a heavy spec truck(cab&chassis;there is one in the pics section here on this web.truck is gray with red rims)this truck has or had the 10bolt,5hand hole ,7.25 bolt pattern rims.they bulit this up to 1972 then seized production in this since no one was buying it.that rear ens is the gm HO72 rear with different brake hubs.now trying to find something that was rear in the 60's ,now in 2010 is the same as finding james r. haffa.not happening.so we are looking for a easier solution to a expensive problem. | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | gary cornaglias 1968 c-30 1 ton.....gray prime with red wheels. | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | ...but since 10-lug hubs are available for the 14-bolt it might be worth investigating. I'm unaware of this. I thought I remembered reading it in one of your posts, if you're not aware of it my memory is faulty. Wouldn't be the first time.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more... It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | no,go back to 1967.You could of bought a heavy spec truck(cab&chassis;there is one in the pics section here on this web.truck is gray with red rims)this truck has or had the 10bolt,5hand hole ,7.25 bolt pattern rims.they bulit this up to 1972 then seized production in this since no one was buying it.that rear ens is the gm HO72 rear with different brake hubs.now trying to find something that was rear in the 60's ,now in 2010 is the same as finding james r. haffa.not happening.so we are looking for a easier solution to a expensive problem. I looked at the pictures of that truck. It looks like something that probably had an Eaton HO72, but I can't count the lugs in those pictures and don't see anything else that would identify the rear under it. Those look like typical 16-inch 8-lug wheels to me. Eaton made rears with 10-lugs but I don't believe they were ever put under 1-ton trucks. I'd sure like to see a picture of the rear under your truck.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more... It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | if you look at the that truck it has 5 HAND HOLE RIMS(ONLY ON 1.5 TON)FIVE LUG FRONT(ONLY ON 1.5 TON).THIS IS A HEAVY SPEC TRUCK(1.5TON).ALL18" AND19.5" WERE HO72 REARS.tHAT WAS THE ONLY REAR USED IN THESE TRUCKS.ALL OF MINE HAVE THE HO72 REARS.SINCE THE RACE TRUCK WAS GIVEN A FRESH REAR WITH ALL HANDMADE INTERNALS,WE DID NOT WANT TO CHANGE IT SINCE BIG MONEY WAS PUT IN TO IT.WE YHOUGHT SINCE GRIGG WAS A MACHINEST AND SEEMS TO KNOW ALOT ABOUT THESE TRUCKS AND HIS PRIVY OF KNOWLEDGE ON ADAPTERS,HE WOULD KNOW ABOUT ADAPTERS.AND SINCE THIS FORUM IS ON TON OR MORE TRUCKS,ITHOUGHT SOMEONE ELSE WOULD BE HIP ON THE R-SERIES TRUCKS BUT I GUESS ME AND MR.CORNAGILLA ARE THE ONLY ONES WITH THESE TRUCKS.DID YOU EVER SEE 16" 5(FIVE) HAND HOLE RIMS......EVER!NEVER WERE MADE....NEVER!IF YOU TAKE HIS PICTURE SAVE IT ON YOUR PICTURES ,THEN ZOOM IN YOU WILL SEE 10 LUGS REAR AND FIVE FRONT. | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | ...WE DID NOT WANT TO CHANGE IT SINCE BIG MONEY WAS PUT IN TO IT.
WE YHOUGHT SINCE GRIGG WAS A MACHINEST AND SEEMS TO KNOW ALOT ABOUT THESE TRUCKS AND HIS PRIVY OF KNOWLEDGE ON ADAPTERS,HE WOULD KNOW ABOUT ADAPTERS.
AND SINCE THIS FORUM IS ON TON OR MORE TRUCKS,.. If money is not a problem try some adapters. I know adapters are out there, but I have no experience with them, so other than pointing you toward a google search for Adapters I can't offer much help on them. ( Edit) I do know about these adapters which were used to run 20" and work just the same for the newer 22.5" rims. However they are extremely hard to find, but as I mentioned, if something is out there (actually does exist) and you want to find it then chances are you can, I did. This section is for 1 tons only, the big bolts section deals with trucks larger than a ton, which sounds like your truck more resembles than a 1 ton. Sorry I don't have all your answers or know about your special truck. I know more about the Advance Design trucks and about the late model 5 and 10 lug axles. I know very little about the trucks in between, like yours. Grigg | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | Well right or wrong all I've done is try to help. Clearly my help is not desired and I'll now withdraw from this thread.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more... It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Jan 2008 Posts: 28 Apprentice | | Apprentice Joined: Jan 2008 Posts: 28 | what is wierd on these truck is that they have the same end caps as on the newer 3500hd's.meaning the end cap that holds the axle on the tube has five bolts and so doesmy 70's chevies.but the actuall center section is HO72 and the newer is dana 80.which according to rock climbers is a junk rear meaning they brake easily.my uncle who is a x-machinest for KRUPPS in germany says if I can get 4 rims he'll machine a plate to weld in and should work.so now the 2nd question where to get 4 rims....know of any for sale grigg | | |
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