Differences in part numbers for cranks?

PM-Performance

PM-Performance

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I am at the point I am looking for a replacement crank for my rebuild and puzzled by all the part numbers for the cranks.

I was led to believe all the cranks from 07-14 GT500 wise were the same crank?
But Ford lists the
07-10 as this: 7R3Z-6303-A
13-17 as this: DR3Z-6303-A
Cobrajet as this: M-6303-C54SC4

What is the difference in all these cranks as I am utterly confused and thinking this is a ploy by Ford to confuse everyone and charge more for diff part numbers?
 
Robin Lawrence

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PM-Performance said:
I am at the point I am looking for a replacement crank for my rebuild and puzzled by all the part numbers for the cranks.

I was led to believe all the cranks from 07-14 GT500 wise were the same crank?
But Ford lists the
07-10 as this: 7R3Z-6303-A
13-17 as this: DR3Z-6303-A
Cobrajet as this: M-6303-C54SC4

What is the difference in all these cranks as I am utterly confused and thinking this is a ploy by Ford to confuse everyone and charge more for diff part numbers?
Click to expand...
From what I have found in my research there are 2 Part numbers for the 5.4 and 5.8 crankshafts


F75Z-6303-AC Is the part number that I get for the 5.4 cranks.
DR3Z-6303-A is the number for the 2013 to 2014 5.8 cranks. I have been told the 5.8 come with the heavy metal required for the extra weight of the Mahle Piston in the 5.8. Also I have been told that the 2013 and 2014 harmonic balancer bolt hole is drilled deeper than the previous 5.4 cranks.
I am going to order the early crank to have a look and verify what I have been told.

Robin
 
PM-Performance

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Robin Lawrence said:
From what I have found in my research there are 2 Part numbers for the 5.4 and 5.8 crankshafts


F75Z-6303-AC Is the part number that I get for the 5.4 cranks.
DR3Z-6303-A is the number for the 2013 to 2014 5.8 cranks. I have been told the 5.8 come with the heavy metal required for the extra weight of the Mahle Piston in the 5.8. Also I have been told that the 2013 and 2014 harmonic balancer bolt hole is drilled deeper than the previous 5.4 cranks.
I am going to order the early crank to have a look and verify what I have been told.

Robin
Click to expand...
Interesting on the weighting thing. That I have not read. I do have mahle's though.
I have read about the hole being drilled deeper, but wasn't sure if that was a standard across the board thing or not.

I just measured my crank from my Ford Racing crate motor ( M-6009-C54SC4) and it is 3.5" deep. I think they quoted that as a "Cobrajet" crank
 
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Catmonkey

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PM-Performance said:
I am at the point I am looking for a replacement crank
Cobrajet as this: M-6303-C54SC4
Click to expand...
This is a standard GT500 crankshaft that was packaged and sold as Ford Racing. It's been discontinued for a while. The other numbers are sold over the parts counter. Supposedly Ford had crankshafts made for the Cobrajets, that were used in the original engines and were not sold through production channels. If anything these were likely stock blanks machined somewhat differently. As long as you have the internals balanced, I don't know that heavy metal plugs will make any difference. If needed, it will be added as part of the balancing process.
 
PM-Performance

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Catmonkey said:
This is a standard GT500 crankshaft that was packaged and sold as Ford Racing. It's been discontinued for a while. The other numbers are sold over the parts counter. Supposedly Ford had crankshafts made for the Cobrajets, that were used in the original engines and were not sold through production channels. If anything these were likely stock blanks machined somewhat differently. As long as you have the internals balanced, I don't know that heavy metal plugs will make any difference. If needed, it will be added as part of the balancing process.
Click to expand...
Supposedly JDM still has the Ford Racing cranks in stock, there is a premium for them though.
I guess it would be nice if someone could confirm the bolt hole depth on a stock gt500 crank for good measure. There is so much back and forth on this, and part numbers, but the reason I ask is because the first one is $300 from Ford. The second one is $1339 from Ford and the last one is $700 from JDM
 
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From the 2013 Ford Racing Catalog:

5.4L COBRA JET CRANKSHAFT
M-6303-C54SC4
• Service replacement part for the 2008 and 2010 Mustang Cobra Jet race car
• Original equipment for 2007-2011 Shelby GT500
• Fits most 5.4L blocks
• Forged steel
• 106 mm stroke
• Standard journal diameters
• 8-bolt flywheel
• Damper bolt hole counter bored to strengthen crank snout for supercharged applications

Crankshaft list price at the time of the catalog was $350. That doesn't mean that JDM doesn't do any other processes to that crankshaft that may inflate the price. I'm not sure the original crankshafts are still available through Ford, so it may be a seller's market. More food for thought. Why would the 13-14 have a deeper bolt hole when Ford used the same crankshaft bolt for all model years?
 
PM-Performance

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Catmonkey said:
From the 2013 Ford Racing Catalog:

5.4L COBRA JET CRANKSHAFT
M-6303-C54SC4
• Service replacement part for the 2008 and 2010 Mustang Cobra Jet race car
• Original equipment for 2007-2011 Shelby GT500
• Fits most 5.4L blocks
• Forged steel
• 106 mm stroke
• Standard journal diameters
• 8-bolt flywheel
• Damper bolt hole counter bored to strengthen crank snout for supercharged applications

Crankshaft list price at the time of the catalog was $350. That doesn't mean that JDM doesn't do any other processes to that crankshaft that may inflate the price. I'm not sure the original crankshafts are still available through Ford, so it may be a seller's market. More food for thought. Why would the 13-14 have a deeper bolt hole when Ford used the same crankshaft bolt for all model years?
Click to expand...

now you see why I am confused right?
All the Ford parts sites list the OEM crank as avail for order.
Not sure the 13/14 is any deeper, but that is a valid question as well
 
Dusten

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PM-Performance said:
Interesting on the weighting thing. That I have not read. I do have mahle's though.
I have read about the hole being drilled deeper, but wasn't sure if that was a standard across the board thing or not.

I just measured my crank from my Ford Racing crate motor ( M-6009-C54SC4) and it is 3.5" deep. I think they quoted that as a "Cobrajet" crank
Click to expand...
correct that is a CJ crankshaft. the standard 5.4 crank is 2"
 
PM-Performance

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RedVenom48 said:
No, its exclusivity. Anything attached to Trinity, legacy or still in production get the Trinity tax.
Click to expand...
Thanks for confirmation.
It’s silly to be honest, but I guess that’s capitalism right? Lol.
I will be ordering an oem crank at that $300 mark in the upcoming days. Just wanted to make sure I wasn’t missing something before I pulled the trigger
 

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