Just wanted to post some photos showing what can happen when a driveshaft comes into contact with other vehicle components.
The first 2 photos show an aluminum shaft that has been damaged by an emergency brake cable. In this case 1/4" more clearance would have made all the difference. Instead, this shaft has been seriously compromised and would shortly have been destroyed. Either by the cable cutting it completely in 1/2 or by the shaft twisting in two. The other photos show a steel shaft from a large box truck that came in for repair while I was writing this thread. It has been completely cut in 1/2. One of the photos shows the shaft after Robert retubed it.

 

To add on the e-brake support bolt, for those with a 4" DS and lowered vehicles, especially those who trimmed sections off their bump stops, watch out!... especially if you decide to carry rear passengers.

Makes me want to relocate mine even though it appears to have sufficient clearance.

For a visual, here's what we're talking about..

Rear center section of tunnel, e-brake cable (for passenger side) support bracket and bolt, directly above driveshaft.

 

Is this from a 2005-up Mustang?
Mike E

 

Robert,

I like your presence on these forums more and more everyday. You have been very helpful to your customers.

Keep it up!

 

[quote=mikeelia;1069540]Is this from a 2005-up Mustang?
Mike E[/quote
Hi Mike,
No, the aluminum shaft was off of a late 90's Mustang. This thread is not intended to be a scare tatic to sell more 3.5 inch diameter driveshafts. It is intended as an informational tool to help you make an informed purchase decision. Some have claimed that the 1/4 inch added clearance the 3.5 provides over the 4.0 diameter makes little or no difference. This photo proves this to be a false statement, don't you agree? As time goes on with the 2005 and up GT's this will end up happening to someone, whether it is with a stock driveshaft or a aftermarket aluminum shaft. All you need is for your emergency brake cable to start sagging, some knucklehead at the muffler shop to position a clamp the wrong way, your exhaust system starts rusting badly and sagging the list can go on and on. If you can purchase a driveshaft that gives you alittle extra leeway at a comparable price why wouldn't you? By the way, our 3.5 inch diameter shaft has a higher torsional yield rating than the cut-down Ranger driveshafts that most, if not all of the competition sells. These shafts have .083 wall tubing. We once were able to purchase these 4.0 inch components seperately, but now like most, if not everyone else our 4.0 diameter driveshafts are shortened Ranger driveshafts. Some of these driveshafts right out of the box have balance issues because of the mass production of these shafts. Without giving up too much info for the competition to latch onto, the way that these issues are addressed determines whether they can become an acceptable Mustang shaft or not. This, we believe is why some say adjust the pinion angle, no adapter, must have been damaged in shipping etc. The right know-how and equipment goes the little extra mile that can make all the difference in the world!
Robert

 

The OEM driveshaft is 3.5", correct?

 

I installed a 4" Shaftmaster DS recently, the 3.5" DS was not available when I bought mine, and I have no clearance issues or vibration on my lowered '06 GT. I probably would not have bought a 3.5" DS if it was available because of the extra $$, but I am completely satisfied with the one I bought.

 

I don't want to answer you incorrectly on this. From LEO 06GT's pictures of his install I would guess that the rear shaft is 3.0 inch in diameter and the front appears to be 3.5 tappering down to 3.0 inch. I would PM Taco Bill or LEO 06Gt and see if they could measure their OEM driveshaft so you know precisely what diameter it is.
Robert

 

I found this on my Mustang Specs document regarding the driveshaft for the GT

(52.3) Overall Length

 

We seem to be stirring up some emotions from this thread and have people claiming that we are saying things that we never have said. For the record, we are not saying that the 4.0 inch aluminum driveshaft is unsafe to use, we never said this. We still offer this shaft ourselves so why would we say it's unsafe. We simply are offering our customers what they asked for. An alternative. We fully expect that in time everyone will be offering this option. In all my 25 years of repairing driveshafts I have seen quite often the damage that can be caused from objects rubbing on a driveshaft's tube as shown in our photos. We feel that we are providing any potential customer with information to make their call on which way they would like to go.
Robert
Note:
Our critical speed rating for our driveshafts come from using the driveshaft calculator on Wallace Racing's web-site. On Mark William's web-site their critical speed rating for a shaft this length is over 8000 rpms. Wallace Racing uses only the tube length in their calculation whereas Mark Williams uses center to center of u-joints. The aluminum shaft that is being used on these mustangs use on the average 10 inches less tubing than on a driveshaft for pre '05 Mustangs. Dana Corp. ratings normally have lower ratings(more conservative) than anyone else. For instance they rate the 1330 series u-joints that are used in these driveshafts to be good for 150 ft. lbs. torque and a maximum of 5000 rpms.