My 01 cobra has the 03/04 6 speed tranny in it, does That mean they had to switch over to the aluminium drive shaft when they did it or could I still have the original?
aluminum driveshaft is it worth it?
- Thread starter AJMAJOR
- Start date
Crawl under your car and look.. its not hard to see the shiny difference...
1979-2004 Ford Mustang Driveshaft Info
1. The 2003-2004 Mustang Cobra has an IRS with T56 transmission. DS is already AL in 2003-2004 Mustang Cobras; so, there is no need to upgrade.
It is a 27-spline and measures 43.5”, at least for the ‘03 It fits the 1999-2001 Mustang Cobra with upgrade to T56 transmission. It costs $400+.
2. The 1999-2001 Mustang Cobra has an IRS with T45/T3650 transmission transmissions respectively. The length between these two transmissions differs by only 1/8.” It is a 31-spline and measures 44.5”. A Ford “J”AL DS which is 45.5” will purportedly “fit” because of the stiffer IRS mount, but is very tight. A Ford “J”AL DS costs $300.
3. The 1996-2004 Mustang GT has an SRA with T45/T3650 transmission. It is a 31-spline and measures 45.5”. A Ford “J”AL DS costs $300.
4. The 1979-1995 Mustang GT has an SRA with T5 transmission. It is a 28-spline and measures 45.5”. A Ford “G”AL DS costs $270.
Note: Yokes, Spline-counts, u-joint sizes and such
Cobra T56 requires 27-spline yoke, while most after market beefed T56’s are 31-spline.
Note: Confirmation that only 03 (and possibly 04 Cobra) uses GM 27 spline yoke!
2001 gt t45 swap - Ford Mustang Forums : Corral.net Mustang Forum
But Ford Racing Cobra DS’s are sold as 31 spline now and Borg Warner documents that 03-04 cobra spline count is 31.
I cannot confirm yet that 2000 Cobra R T56 output shaft was 31 spline as well.
http://www.svtperformance.com/forums/cobra-rs-25/356253-00-r-trans-slip-yoke-question.html
TR3650 to T56 swap - 2003-04 Mach 1 Registry Owners Club
http://www.svtperformance.com/forum...-t56-ford-stamped-31-spline-output-shaft.html
Ford 31-spline yoke works for T45 and T3650 transmissions and uses 1330 u-joints.
The 2003-2004 used a bigger irs dfify flange and 1350 u-joints…..
Ford 28-spline yoke works for T5 transmissions and APPEARS TO BE 1330 u-joint toward the end of the Fox body years and other sizes for various earlier years.
******************************************************
A P71 AL DS can be bought off ebay for cheap ($60-$75). It is ~55.5."
and 31 spline yoke can be swapped over to the AL DS.
AL DS cutting and balancing:
A cutting and balancing of a DS shouldn’t run more than $100…more like $170 if they replace the joints for you.
An AL DS is something you get because you want it.
If you want it, get it.
1. The 2003-2004 Mustang Cobra has an IRS with T56 transmission. DS is already AL in 2003-2004 Mustang Cobras; so, there is no need to upgrade.
It is a 27-spline and measures 43.5”, at least for the ‘03 It fits the 1999-2001 Mustang Cobra with upgrade to T56 transmission. It costs $400+.
2. The 1999-2001 Mustang Cobra has an IRS with T45/T3650 transmission transmissions respectively. The length between these two transmissions differs by only 1/8.” It is a 31-spline and measures 44.5”. A Ford “J”AL DS which is 45.5” will purportedly “fit” because of the stiffer IRS mount, but is very tight. A Ford “J”AL DS costs $300.
3. The 1996-2004 Mustang GT has an SRA with T45/T3650 transmission. It is a 31-spline and measures 45.5”. A Ford “J”AL DS costs $300.
4. The 1979-1995 Mustang GT has an SRA with T5 transmission. It is a 28-spline and measures 45.5”. A Ford “G”AL DS costs $270.
Note: Yokes, Spline-counts, u-joint sizes and such
Cobra T56 requires 27-spline yoke, while most after market beefed T56’s are 31-spline.
Note: Confirmation that only 03 (and possibly 04 Cobra) uses GM 27 spline yoke!
2001 gt t45 swap - Ford Mustang Forums : Corral.net Mustang Forum
But Ford Racing Cobra DS’s are sold as 31 spline now and Borg Warner documents that 03-04 cobra spline count is 31.
I cannot confirm yet that 2000 Cobra R T56 output shaft was 31 spline as well.
http://www.svtperformance.com/forums/cobra-rs-25/356253-00-r-trans-slip-yoke-question.html
TR3650 to T56 swap - 2003-04 Mach 1 Registry Owners Club
http://www.svtperformance.com/forum...-t56-ford-stamped-31-spline-output-shaft.html
Ford 31-spline yoke works for T45 and T3650 transmissions and uses 1330 u-joints.
The 2003-2004 used a bigger irs dfify flange and 1350 u-joints…..
Ford 28-spline yoke works for T5 transmissions and APPEARS TO BE 1330 u-joint toward the end of the Fox body years and other sizes for various earlier years.
******************************************************
A P71 AL DS can be bought off ebay for cheap ($60-$75). It is ~55.5."
and 31 spline yoke can be swapped over to the AL DS.
AL DS cutting and balancing:
A cutting and balancing of a DS shouldn’t run more than $100…more like $170 if they replace the joints for you.
An AL DS is something you get because you want it.
If you want it, get it.
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I have the J shaft on mine. Tight fit to get it in, but it fits fine
I run the 03 driveshaft with my T56. All I did was swap the pinion flange on the IRS so I could use the correct U joints for an 03. That combined with an aluminum flywheel and I do notice the car revs up quicker and takes a little more gas pedal to start from a stop. I also don't have the rpm hang that I used to have with the 01 driveshaft. I did the T56, aluminum flywheel/driveshaft install all at once so I don't know which one made the difference.
Overall I'd say go with it. It will drop some weight at the very least. I would only hold off if you are planning on swapping to a different transmission at some point so you know you are getting the right shaft and won't have to change it later on.
Overall I'd say go with it. It will drop some weight at the very least. I would only hold off if you are planning on swapping to a different transmission at some point so you know you are getting the right shaft and won't have to change it later on.
For me it was worth it. Finally my driveline vibrations are gone, after rebuilding the whole drivetrain and suspension the driveshaft was the only stock thing left on the car. It's now smooooth, and there is another shiny thing to look at under the car!
I have one question. I've read the 03/04 pinion flange is thicker than the pinion flange of the 01 cobra. Is that correct? When I buy now a 03/04 pinion flange, cause I have to change the pinion seal anyway and use the 01 cobra spline yoke with a hybrid u-joint, how much shorter is the driveshaft then? What's with the length of the yokes? Is 03/04 spline yoke shorter than the 01 yoke spline?
I think the yokes are 7.5" for all.
As far as the rear pinion flange being thicker, do you mean longer somehow??
I know the pinion flange diameter is larger for the 1350 joints.
You're going to have both flanges on you soon. Please let us all know.
I don't think the 03-04 flanges are any longer, but they may be..
The 99-01 cobra T45 to IRS DS is 44.5" so the terminator DS (43.5") will fit with an inch to spare..probably ok.
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hmm ok, but an inch isnt that a bit much? I think I will replace my pinion flange with a Termi one and use the stock spline yoke with a hybrid yoke.
If you think the terminator pinion flange will change the actual length, fine.
Let us know what the yoke buys you for length, as I don't know if longer slip yokes are longer in the joint part where you need them to make more length, they might be; I have the feeling they are longer in the spline section. It will nice to add to the knowledge base.
Yes 1" from the terminator DS plus the bit (1/2-3/4") 'slop" that the original DS had is quite a bit.
3/4" is the general rule. I think this is for body flex in the unibody subframe...pie-tin.
subframes help.
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I dont think it, but then I dont have to change the flange yoke
But I just measured the spline yoke of the Cobra driveshaft and it's 6.5" long (Center of u-joint to the front of yoke)
On the Ford Racing page, is the length of the spline yoke for the TR3650 and you're right, it's about 7.5" long.
I will order the hybrid u joints and will the spline yoke of my 01 cobra.
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