Difference between 99 24v & 04 CR short blocks?

Discussion in 'Tow Rigs and Trailers' started by untchabl, Dec 25, 2019.

  1. untchabl

    untchabl On the rocks

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    Mar 30, 2009
    Location:
    Bear Creek, NC 27207
    I just bought an 04 Ram 3500 with the Common Rail with a hole in the block. I have a beat up but complete, running 99 24v truck with a bad auto trans. Can I use the 99 24v bottom end and put the 04 head on it and swap it in the 04 truck? My Google searches are some saying it will work but majority says it won't.
     
  2. Junkyard Dog

    Junkyard Dog Well-Known Member

    Joined:
    Mar 21, 2005
    Location:
    Sanford, NC
    Is it HO motor or non? I think piston bowls were different between the two. The non HO CR may have the same bowl design though. Seems like I remember the 24v block being more similar to a 12v and a CR having some different casting shapes. If you need I have a CR short block in storage I can get some photos of if needed.
     
  3. untchabl

    untchabl On the rocks

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    I'm pulling the CR engine out of the truck and tearing it down. Don't want to pull the 24v from the running 99 truck if it won't work.

    How do I know if it's an HO CR engine?
     
  4. Junkyard Dog

    Junkyard Dog Well-Known Member

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    Mar 21, 2005
    Location:
    Sanford, NC
    What HP is it. Will be either a 305/550 or 325/600. Their were some piston bowl differences between the two of I ain't mistaken. Want to say the 305HP ones were similar if not the same as your 24v
     
  5. untchabl

    untchabl On the rocks

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    I'll check when I get home this evening and see if it's an HO or not.
     
  6. untchabl

    untchabl On the rocks

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    According to my VIN number, it's an HO engine. The sticker on the engine is missing.
     
  7. Jody Treadway

    Jody Treadway Croc wearing fool Moderator

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    Location:
    Hendersonville, NC
    All 04 are HO. 04 1/2 are the 600 ft/lb version
     
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  8. untchabl

    untchabl On the rocks

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    @Jody Treadway do you have any knowledge on the common rail vs the older 24v short blocks?
     
  9. Jody Treadway

    Jody Treadway Croc wearing fool Moderator

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    Mar 20, 2005
    Location:
    Hendersonville, NC
    Not specifically
    The resident Cummins expert here is @Hurdt299
    I don't know the block differences like he does
     
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  10. Hurdt299

    Hurdt299 Well-Known Member

    Joined:
    Nov 13, 2006
    Location:
    Asheville, NC
    Short answer is no, you can't do it. The CR has three different pistons (03-04, 04.5-05 and 06-07) 04 and 04.5 were different due to the 3rd injection event added in 04.5. This event was necessary to create higher EGTs to keep the added Cat cleaned out. If you buy a used motor you need to be sure 100% which one you have. The 8th digit of the VIN on your truck will be either a 6 if it is an 04 and a C if it is an 04.5. 04.5 also has a bigger turbo. The 03/04 has an HE341 and 04.5-07 has the HE 351. These trucks are getting old enough now that you cannot tell by looking at things like turbo. I have sold many used HE351s to people that were putting them on their 03/04 trucks. None of the CR pistons will have the same bowl design as a 24 valve. The timing gears are straight cut in a CR, where they are helical (angle) cut in 24 valve and older, so your CP3 would not work with a 24 valve cam gear. The timing gear case, from what I have read (I cannot personally attest to this), has a different bolt pattern on a CR, so you cannot swap cases to put your CP3 on the 24 valve. If you have any more questions, feel free to text me at 828-691-5196.
     
  11. Jody Treadway

    Jody Treadway Croc wearing fool Moderator

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    See what I mean?
    Dude knows his stuff!
     
  12. untchabl

    untchabl On the rocks

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    Mar 30, 2009
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    Bear Creek, NC 27207
    @Hurdt299 the 8th digit of the VIN is a C, so it should be an HO. If you don't mind, I'll text you tomorrow and get some more knowledge from you. Thanks for all the info so far.
     
  13. Hurdt299

    Hurdt299 Well-Known Member

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    Nov 13, 2006
    Location:
    Asheville, NC
    Appreciate it brother

    Glad to be some help. Text me anytime.
     

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