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    Guest Message by DevFuse
     

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    24 Inch Hubs To 22.5 Conversion



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    10 replies to this topic

    #1 OFFLINE   genster

    genster

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    Posted 23 July 2008 - 04:33 PM

    hey guys, i currently run 12r24 tires with 6 spoke hubs on the front axle of my mack and am wondering what all would be involved in swapping them to 22.5 6 spoke hubs to run a wider super single or flotation tire. the current height is 48 inches tall, and i want to stay at that height if possible. will the brakes be too large to fit the 22.5 hub and would it bolt up?? any help will be greatly appreciated.

    #2 OFFLINE   bobo

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    Posted 23 July 2008 - 10:03 PM

    hey guys, i currently run 12r24 tires with 6 spoke hubs on the front axle of my mack and am wondering what all would be involved in swapping them to 22.5 6 spoke hubs to run a wider super single or flotation tire. the current height is 48 inches tall, and i want to stay at that height if possible. will the brakes be too large to fit the 22.5 hub and would it bolt up?? any help will be greatly appreciated.



    hey, the brakes will be the same no matter what size wheel you run, unless you have roto chambers? what you need to find out is the inner bearing set number, and cross reference it over to the smaller hub. any parts jobber can do this for you. why stay with the spokes? why not change over to a hub pilot? the hub pilot will most likely be cheaper to buy. tire size you might want to run would be 385, 425, or 445, But they are not cheap!! Ive done a number of hub/wheel change over ask away!

    #3 OFFLINE   HK Trucking

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    Posted 24 July 2008 - 05:25 AM

    hey guys, i currently run 12r24 tires with 6 spoke hubs on the front axle of my mack and am wondering what all would be involved in swapping them to 22.5 6 spoke hubs to run a wider super single or flotation tire. the current height is 48 inches tall, and i want to stay at that height if possible. will the brakes be too large to fit the 22.5 hub and would it bolt up?? any help will be greatly appreciated.


    Actually, you'll need 20" Dayton 6 spoke hubs to go with 22.5" (tubeless) Dayton rims.

    Be sure to get the rims with the proper offset, as there are frequently clearance issues between the inside edge of the wide rims and the tie rod ends on certain front axles.

    As stated previously, unless you want to stay with the spoke hubs for appearance reasons, a set of 10 stud unimount hubs would enable you to use any 10 stud unimount wheel of any diameter or width (of course you'd have to also use the unimount type brake drums with the unimount hubs).
    "If You Can't Shift It Smoothly, You Shouldn't Be Driving It"

    #4 OFFLINE   genster

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    Posted 24 July 2008 - 08:17 PM

    hey, the brakes will be the same no matter what size wheel you run, unless you have roto chambers? what you need to find out is the inner bearing set number, and cross reference it over to the smaller hub. any parts jobber can do this for you. why stay with the spokes? why not change over to a hub pilot? the hub pilot will most likely be cheaper to buy. tire size you might want to run would be 385, 425, or 445, But they are not cheap!! Ive done a number of hub/wheel change over ask away!



    what are roto chambers?? ive never heard of them before. i'll just need to find out what is cheaper, changing hubs and running a 20 inch dayton, or changing hubs and running a hub pilot for 22.5 rims. i would think open 22.5's would be cheaper and easier to find, but i could be mistaken. hub pilots are nicer in that the rims wont spin, and you dont need to make sure its centered. i know those tires arent cheap, at work we put a pair of 385's on a truck and they were $7-800 a piece. ahhhh, its only money!....

    Edited by genster, 24 July 2008 - 08:25 PM.


    #5 OFFLINE   genster

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    Posted 24 July 2008 - 08:24 PM

    Actually, you'll need 20" Dayton 6 spoke hubs to go with 22.5" (tubeless) Dayton rims.

    Be sure to get the rims with the proper offset, as there are frequently clearance issues between the inside edge of the wide rims and the tie rod ends on certain front axles.

    As stated previously, unless you want to stay with the spoke hubs for appearance reasons, a set of 10 stud unimount hubs would enable you to use any 10 stud unimount wheel of any diameter or width (of course you'd have to also use the unimount type brake drums with the unimount hubs).


    if i went to the 10 stud, then i would need new brakes totally, or just brake drums?? im assuming just drums which would mount thru the studs. but if i went with the 20 inch dayton spoke hubs would i need new brakes also? my drums currently measure 18 inches in diameter, and that seems pretty big for a 20 inch hub to fit over for clearance issues.

    is that the 2.5 inch rule? a 20 inch spoke uses 22.5's tubeless, and a 22 inch spoke uses 24.5 tubeless?

    thanks to all for putting up with my ignorance! :unsure:

    #6 OFFLINE   HK Trucking

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    Posted 24 July 2008 - 09:21 PM

    if i went to the 10 stud, then i would need new brakes totally, or just brake drums??


    Just drums.

    im assuming just drums which would mount thru the studs. but if i went with the 20 inch dayton spoke hubs would i need new brakes also? my drums currently measure 18 inches in diameter, and that seems pretty big for a 20 inch hub to fit over for clearance issues.


    You've got 16.5" brakes - the drum is 18" outside diameter.

    is that the 2.5 inch rule? a 20 inch spoke uses 22.5's tubeless, and a 22 inch spoke uses 24.5 tubeless?


    Yes, that's pretty much how it works.
    "If You Can't Shift It Smoothly, You Shouldn't Be Driving It"

    #7 OFFLINE   Maxville

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    Posted 13 August 2008 - 08:28 PM

    What model of truck are you dealing with....

    I just did a conversion on a heavy axled DM886sx, Beautiful old flintstone hooded super heavy axled setup. We started with just pulling the hubs off. bearings and seals were totally different, I believe this truck has the 23,000lb front axle.
    I have a couple of 20,000lb or 18,000lb axles lying around so we pulled an axle in the shop and proceeded to start measuring..........

    we ended up removing everything from the king pins out from the heavy axle and replacing it with the "lighter" axled "stuff" we had to retain the original steering lever and both cross steering levers.

    The king pins on the heavier axle were totally different, however the tapered hole where the king pin resides in the axle was the same. so the "lighter" set of king pins worked perfectly. If you have just a 18 or 20 front then all you should need is the hubs and drums (seals etc).

    If you end up needing to do what we did, your cheapest bet would be to buy a complete front axle to get your parts, around here that would run a bout $1000.00.

    #8 OFFLINE   David

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    Posted 14 August 2008 - 08:22 PM

    I have a DM897 with 22.5. I'll trade you what ever is necessary for the swap.

    #9 OFFLINE   genster

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    Posted 14 August 2008 - 10:01 PM

    1988 DM 690 SX with a 17-18K front axle. I'm wanting to do the front axle at least to get more flotation, since its a 5,000 gallon tank spreader and I dont want as much compaction. I'm thinking the tandem rears have a fairly decent sized foot print because of the large tire diameter.

    on another note, are super singles (385, 425 etc.) sizes made or popular in a 24.5 rim?? I've only seen them in 22.5 rim size.

    Maxville, that looked like a nice rollover on that tank spreader of yours :unsure: .....and i think you guys had a few solids in the lagoon too!

    Edited by genster, 21 August 2008 - 08:37 PM.


    #10 OFFLINE   genster

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    Posted 21 August 2008 - 08:47 PM

    I have a DM897 with 22.5. I'll trade you what ever is necessary for the swap.


    what for axle is it? 22.5 daytons?

    #11 OFFLINE   David

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    Posted 21 August 2008 - 09:35 PM

    what for axle is it? 22.5 daytons?


    My mistake. It has 22" (or 24.5") Daytons




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