Check out this link...This is the first I've heard of this and am not sure what to think...

http://www.blueovalnews.com/plugins/p2_news/printarticle.php?p2_articleid=237

ShelbyWise

Here is a copy of the actual article re: GT500 Crankshaft Failures...

2007 Shelby Mustang GT500 Engine Failures?
By Lane, Robert
Published: April 21, 2006


(DEARBORN, MI) - StangsUnleashed.com - Dearborn, we may have a problem. An engine problem with the 2007 Shelby GT500, to be specific. StangsUnleashed has learned that the un-thinkable could happen: the upcoming launch of the GT500 could be delayed or pushed back due to an alleged engine crankshaft problem.
Sources close to the 2007 Shelby GT500 program are alleging that the crankshafts in the 5.4L GT500 engines are fracturing or breaking at the snout (nose) where the engine damper rides. The sources are alleging that the GT500 crankshaft breakage can be attributed to two complimentary issues. According to our reliable sources, Ford designed a crankshaft damper specifically for the GT500, but the damper weighs in at a hefty 26 pounds.
The weight of the GT500's damper, combined with the stress of the SuperCharger pulling on the crankshaft may be placing too much stress on the crankshaft's snout, which is causing the failures. By comparison, the balancer on the SVT Lightning's 5.4L SuperCharged engine weighs less than 1/2 of the GT500s. The GT500's balancer is similar to the Ford GTs, however is totally different from the SVT Lightning. Unlike the GT500, the SVT Lightning uses a stand alone pulley bracket support system, which threads into the damper itself.
Should the GT500 crankshaft allegations prove to be true and the launch of the GT500 is delayed, it could have a potentially devastating affect, not only on the GT500, but it could throw off the timing of other SVT products like the 2008 GT500. Moreover, consumers' feathers are already ruffled over the GT500 due to a variety of issues. Even though order banks opened weeks ago, Ford has failed to provide exterior color examples. They have also failed to provide consumers with absolute horsepower/torque ratings, MSRP pricing and keep in good communication with their PowerLease customers.
Could a crankshaft issue/delay be the reason why Ford has not released any new information on the 2007 Shelby GT500? On 19 April, we asked Ford questions about this story, however, they never responded.

ShelbyWise

Shelbywise, 07 Shelby, or anyone else out there: Any updated info, rumors, etc on this?:confused:

98Snake...Check out the link below.

ShelbyWise;)

http://www.stangsunleashed.com/forums/index.php?showtopic=808&hl=gt500+crankshaft

Looking at the block I noticed it is stamped/roll marked Roush?? so is roush making all motors for the ford mustangs or are my eyes playing tricks on me...

They had 1 crankshaft snap at the nose.This is old news.This was not a production motor/car.They do a lot of testing on the motors,frames and just about anything they can possibly tweak.I've seen a Shelby with a v10 but you won't see it in production.They take these FU1 and FU2(these are trial build cars,1st build and 2nd build)and they beat them to hell to see how much abuse they can take.They take the limits off in the computer(rpm limits,timing,speed and a list of other parameters) and see what kind of data they get.I hope you get what I am telling you.

As far as Roush goes,they do a lot of testing for Ford.About a year ago I saw Roush taking trailer loads of Shelby's out of the plant to do various tests and to make after market parts.They have close ties.This is business as usual!Roush does not make Shelby engines.Each motor is built by hand in a 2 man team and each motor has a tag with signatures of the 2 men building it.It is built at the Romeo engine plant.

Did you see 4.6L terminator engine.That is not a Shelby engine.The other is a prototype not production engine.

They had 1 crankshaft snap at the nose.This is old news.This was not a production motor/car.They do a lot of testing on the motors,frames and just about anything they can possibly tweak.I've seen a Shelby with a v10 but you won't see it in production.They take these FU1 and FU2(these are trial build cars,1st build and 2nd build)and they beat them to hell to see how much abuse they can take.They take the limits off in the computer(rpm limits,timing,speed and a list of other parameters) and see what kind of data they get.I hope you get what I am telling you.

As far as Roush goes,they do a lot of testing for Ford.About a year ago I saw Roush taking trailer loads of Shelby's out of the plant to do various tests and to make after market parts.They have close ties.This is business as usual!Roush does not make Shelby engines.Each motor is built by hand in a 2 man team and each motor has a tag with signatures of the 2 men building it.It is built at the Romeo engine plant.

Hi 07Shelby!

Hey, you mentioned that two people build each engine and sign a "tag"....can you specify more about this? In other words, where is it, and if I want documentation, can I easily remove this tag and keep it somewhere?

Thanks,

Terry

It is located on top of the engine on the left hand side.Yes I think it would be easy to take off.I don't know why you would want to take it off though.The tag is made of metal and is nice to show people on the car.

Hi 07Shelby!

Hey, you mentioned that two people build each engine and sign a "tag"....can you specify more about this? In other words, where is it, and if I want documentation, can I easily remove this tag and keep it somewhere?

Thanks,

Terry


Terry,
The metal tag is located on top of the valve cover and is glued on.

All Cobra engines since '96 have been hand-built by two mechanics on the infamous Romeo Niche Line. The signature plate is found on all of these cars on the passenger side valve cover.

I'm with you 07.

If you remove the TAG, you're more lible to miss place it or loose it anyway. Then your stuck. I'm sure it's been put on in such a way that it wouldn't come off under normal wear and tear. Those guys are proud of their engines, and I can't wait to meet them..

All Cobra engines since '96 have been hand-built by two mechanics on the infamous Romeo Niche Line. The signature plate is found on all of these cars on the passenger side valve cover.

It's on the drivers side on the 5.4L.

Hi 07Shelby!

Hey, you mentioned that two people build each engine and sign a "tag"....can you specify more about this? In other words, where is it, and if I want documentation, can I easily remove this tag and keep it somewhere?

Thanks,

Terry

Dave,

Did your name used to be Terry ?

Dave,

Did your name used to be Terry ?

Dave's prob not on any more. Post is 4.5 yrs old. :boohoo:

My metal tag is missing on my 5.4L GT500 crate motor, how do I find a replacement? All the other barcode labels are there?????????? Fortyrag