MacaRowni

Hi Everyone,

New to this forum and hoping to get some sound advice. I ran into some trouble with the V6 Mustang from 2007 (automatic). What better can help me, than people who hopefully know more about this.

Back in 2017 in the summer I drove above 200km/h (120mph+) and my driveshaft exploded (I removed the speed limiter, little did I know...), it was the stock driveshaft. It destroyed a lot under the car and itself. In the end it got replaced with a 05-09 driveshaft from a GT. I actually wanted a new product from americanmuscle but they installed for some reason by their own input a one piece 05-09 GT driveshaft.

This left me for some reason with an unknown *clunk* sound whenever I put it in drive or reverse. Though it didn't bother me that much.

Fast forward a few years and we're in 2021. I wanted to upgrade the rear end as in my opinion the stock rear-end doesn't takes you of the line that well and in corners it just didn't feel that nice and tidy. Due to the differential mostly I think, or that must be in my mind.

So I bought the following:
- Limited slip from Yukon
- 3.73 gears from Yukon
- Bearing kit
- Ford performance friction modifier

So everything got installed and the first impressions were very very good. The old differential was after all very loose and destroying itself and the gears. So it was a good change. The majority of the *clunk* noise is gone. However I got introduced to a plethora of new sounds. Making me return it to the garage as it doesn't feel safe to drive.

2 of the sounds will be resolved as one was unfortunately coming from the pinion bearing. But that will be fixed, another bearing from the wheel made a sound and that also will be fixed. But now here comes the thing...

He noticed that the driveshaft that is under the car, suddenly has room up and down and back and forth, and is currently vibrating a little bit too much. He commented that the driveshaft isn't supposed to be under my car and recommends going back to the stock driveshaft or something different

- Is the GT driveshaft not able to sit under a V6, with changes done to the Differential and Gears?
- Is it OK to go back to the stock driveshaft, without it causing any new issues or slowing it down, is there any impact there performance wise?
- What replacement would be good to do, or just going back to the stock and put the limiter back on?

Hopefully someone can help me out with the questions or maybe even have a solution out of experience.

Looking forward to your replies and input.

houtex

Quote:

In the end it got replaced with a 05-09 driveshaft from a GT. I actually wanted a

That is the problem, full stop. They are different lengths for both the automatic and the manual, as well as the GT vs the V6. Every website lists four different driveshafts for this reason for any '05-10 Mustang, V6 vs V8, manual vs automatic. Not having the correct driveshaft will either tighten things up and make noise and ruin things, or be loose and slop about back and forth and ruin things. In any event, the wrong driveshaft will most likely just ruin things period. Seals, shaft teeth, joints...

Get the correct driveshaft. It will do nothing but help, if not eliminate the problem, but not having the correct driveshaft is a bad move(tm). in my opinion. Proper parts for the car, please and always!

Off topic a little... it sounds like you're saying 'someone else' did the work and acquired/installed the improper driveshaft. If that's the case, well, darn shame that. I'd be at least looking at them askance and not taking my car back to them after this, to be honest....

If it was you... well, don't do that again. Get the right part, don't settle/be in a hurry.

Regardless of the history, it can be fixed, and hopefully nothing bad's happened to either the transmission output or the axle input. Hope that helps, and welcome to the forums! Good luck!

Bert

Houtex covered most of it; a couple other related points:

• one-piece aluminum driveshaft is prone to vibration if the pinion angle is not perfect; plus the pinion angle changes under different load conditions so they are very difficult, if not impossible, to get to run completely vibration free. The ones with CV joints are supposed to eliminate this issue; but they have other issues, like slop in the joints (from what i have read)
• OEM driveshaft has the joint in the middle to help with this issue
• safest thing is to use OEM driveshaft, and don't exceed its speed limit, which means yes you should restore the original speed limiter
• there might be some aftermarket driveshafts that have the center joint and are higher speed rated; you'd need to research that

MacaRowni

Hi @Bert & @houtex ,

Thank you so much for the replies. These answers were exactly what I needed!

In answer to this, if you're willing to read
The whole repairing after the Driveshaft exploded was a complete disaster. It was my first day of vacation, taking the car for a long roadtrip to Italy and back to the Netherlands. The accident happend 4 hours into the trip when I was in Germany... the car got towed away and brought to a random garage by my insurance company. The first three garages didn't want anything to do with an American car, or didn't know what to do with it. In the end it got sent to an official licensed Ford Garage...I asked them to buy a one piece aluminium drive shaft from american muscle for my type of car. Even gave them the exact link.

I followed my roadtrip with a different car. 3 weeks went by and they said they fixed the car. When I came by, my exhaust system was still completely bent and held together with ti-rips.. no joke. I declined this repair and said they had to fix this better. This was also the garage that installed the GT driveshaft. But little did I know at that time they put a 05-09 driveshaft on. And my knowledge was to the part that I thought.. well hey, thats a solution too... until I am reading this from you guys.

I've noted the current garage to buy the OEM part and install it. I will put back the Speed limiter to prevent any issues. I will let you guys know about the repair if it fixed everything in the end. Perhaps I can send the pictures of the exploded driveshaft if you're interested haha...

Thanks again for the knowledge share.

houtex

OH! Well, over there, that's more understandable regarding the why of things! Parts aren't as plentiful, I'm sure, in the emergency needs. Not that it excuses what they did, mind, just a bit more understandable.

Hope it gets all taken care of and workin' for ya!

Bert

the story makes a lot more sense to me now, thanks for the long version . . . that's a really frustrating experience, unfortunately "sh*t happens" as we say here in the states, I guess they have "flakes*" over there in Europe too

* listen to Frank Zappa's "Flakes" on Youtube for the full depth of that reference, LOL