The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!

Ford Racing Suspension Upgrades

it could be checked, but it's prolly close enough, you might want to find a single piece aluminum (not carbon fiber) driveshaft and save about 500 pounds.
and BTW, that 2 piece PITA will double over and smash your hands if you
are not careful removing it.

Blacksheep, I've had a friend of mine who does a little side work with a tuner here in town tell me the one-piece driveshaft causes a vibration when installed. I googled it, and it appears it's quite a common problem.

Have you experienced this? I've tried to look back through the forums, but don't seem to find it as common on here. My car is my daily, and I very much want the one piece, but I don't want to suffer anymore than I have to...

thoughts?
 

Bill Pemberton

0ld Ford Automotive Racing Terror
6,413
5,310
Exp. Type
W2W Racing
Exp. Level
20+ Years
Blair, Nebraska
Have not had with my cars , though have heard mention from some of the guys I know who went with Carbon Fiber ones. Blacksheep Uno would likely have your best answer , as that young man has worked on a zillion Stangs ( Phoenix Race Cars and plenty of customer Mustangs).
 
628
198
My Dynotech aluminum one is smooth as glass up to 150+. I have coilovers and an adjustable UCA and it required just a tiny adjustment to get pinion angle in spec.

There are other great brands out there apparently but be aware that there is one that consistently has issues that are well-documented on this and other forums. The one with the CV joint (that fails over and over).
 

Bill Pemberton

0ld Ford Automotive Racing Terror
6,413
5,310
Exp. Type
W2W Racing
Exp. Level
20+ Years
Blair, Nebraska
Should have mentioned , I did have a vibration with my Boss 302S and it ended up being a bolt on the exhaust system that was hitting underneath at speed - nothing to do with the driveshaft. I know we fixed a friend's Boss with a similar situation , where a hanger had busted but would bang and vibrate under load.

Not very technical , but with my Mustang and my past ACR, the vibrations I had were exhaust related.
 
4,389
4,790
Blacksheep, I've had a friend of mine who does a little side work with a tuner here in town tell me the one-piece driveshaft causes a vibration when installed. I googled it, and it appears it's quite a common problem.

Have you experienced this? I've tried to look back through the forums, but don't seem to find it as common on here. My car is my daily, and I very much want the one piece, but I don't want to suffer anymore than I have to...

thoughts?

The one in my 99 GT has been at 150 mph, the one in my 07 GT500 has been at 125 mph, no issues with either one, I do not like carbon fiber driveshafts for this one reason, if road debris, rocks, whatever crap is bouncing around out there nicks the driveshaft you now have a recipe for disaster. Once the outer..usually glossy, protective clear is compromised it can let in water, grime, grease and like everything that is held together by glue, it will start to degrade. In race cars that stuff gets inspected all the time, and you can find guys with little bottles of clear covering those holes up. The cars I've seen all run aluminum shafts because they are light and dependable without all the delamination drama.
Of course, if you choose to run carbon fiber, there's always this..
https://www.aircraftspruce.com/cata...daPq6D2Pt2OHi8be22DgkdjBZ1JDA0oBoCM3EQAvD_BwE
 
Last edited:

TymeSlayer

Tramps like us, Baby we were born to run...
3,765
2,664
Exp. Type
HPDE
Exp. Level
3-5 Years
Brighton, Colorado
In the Boss, the weights for the OEM two-piece was 39.05 lbs. My DSS one-piece aluminum was 20.27 and my DSS one-piece Carbon Fiber is 17.73 lbs. I have no issues with the DSS driveshaft and have taken it up to 150mph with no noticeable vibration.

Despite @blacksheep-1 concerns, I will throw on the DSS CF one I have but perhaps will laminate it before installation.

Disclaimer: I do not, as a habit do the opposite as blacksheep as he is more in tune to this stuff than I but I do like my Watts Link and look forward to seeing how the CF DS performs on my Boss.
 
4,389
4,790
Changing out the 2 piece, just makes life easier, after wrestling that 2 piece one around, and the extra components are a pain.. IMO, once you decide to change it out, you might as well go with aluminum or CF, I don't know of anyone who makes a steel one anyway, but keep in mind that the weight is probably more advantageous in reducing the overall weight of the car as much as anything else, that weight is awful close to center mass, so it's not like you're accelerating anything 1 foot out from the rotational center, if so, the advantages of CF might be more apparent..but I don't think there is enough there to warrant the possible issues.
 
Yeah, I’m not the type to live with a CF driveshaft on my street car. They’re absolutely necessary on a race car, but mine gets rained on and shiznit. I’ll be happy with an aluminum one.
 

TymeSlayer

Tramps like us, Baby we were born to run...
3,765
2,664
Exp. Type
HPDE
Exp. Level
3-5 Years
Brighton, Colorado
I do have BMR non-adjustable LCAs, FRPP T lowering springs and there was no need to change the pinion angle with the CV in the rear. The DS went on after I had installed the LCAs and other than losing a boot early, it works flawlessly. There was no need for adjustable LCAs.
 
What should the rear pinion angle be? I can't seem to find a set number.

Some of the aftermarket websites say it must be calculated by measuring the front driveshaft angle and the trans output flange, subtract the driveshaft measurement from the output flange measurement, and the answer is what the pinion angle should be.

Sorry for my ignorance; I've not had any experience with 2-piece driveshafts until now.
 
Last edited:
Can't remember the exact correct pinion angle, but you shouldn't need to worry about it if the rear is lowered less than about 2". I had Steeda "Boss" lowering springs on mine which are supposed to lower the rear about .8" (it was actually a bit more than 1" on my car) and ran a Dynotech 3 1/2" aluminum 1-piece DS, and had zero vibrations whatsoever.
 
Last edited:
Can't remember the exact correct pinion angle, but you shouldn't need to worry about it if the rear is lowered less than about 2". I had Steeda "Boss" lowering springs on mine which are supposed to lower the rear about .8" (it was actually a bit more than 1" on my car) and ran a Dynotech 3" aluminum 1-piece DS, and had zero vibrations whatsoever.

The vibrations aren’t my issue... now there’s a very loud “clunking” noise due to play in the stock 2-piece driveshaft. It happens when the clutch is engaged or released. I backed the car up on ramps to investigate, and the driveshaft has about 1/16” of play from front to back, and about 1/8” to 3/16” of slop when you grab it with your hand and twist/rotate it.

There is also a noticeable whine above 65 mph, although again; no vibration.

I took it to Ford for an alignment, and they said it was out of spec (-0.2°) but couldn’t adjust it as my FRPP LCA’s are non adjustable, and I didn’t use an upper link.

Thing is, I 1) don’t know what the spec is, as they didn’t tell me, and 2) I’ll have to wait until the adjustable upper rear control arm comes from Steeda. Even then, I’m not sure it’ll fix this new problem, or what to set the pinion angle at.
 
Can't remember the exact correct pinion angle, but you shouldn't need to worry about it if the rear is lowered less than about 2". I had Steeda "Boss" lowering springs on mine which are supposed to lower the rear about .8" (it was actually a bit more than 1" on my car) and ran a Dynotech 3" aluminum 1-piece DS, and had zero vibrations whatsoever.


https://trackmustangsonline.com/threads/driveshaft-issues-after-suspension-work.14912/#post-222185

Here’s a more detailed write up I did over what I’m having issues with.
 

TMO Supporting Vendors

Top