Thanks Rich!!

 

Sorry gentlmen for taking so long to report my findings. I have been playing with the pinion angle. I still have the vibration/hum at 90 (it has gotten better) but I have gotten rid of the vibrations up to that speed. I have been tuning the pinion a degree at a time. If get all the vibration out of the driveline I will report my settings.

 

I am at +4 degrees and the vibration is 70% gone. I am going to keep trying different angles.

 

Still adjusting the pinion angle, vibration is still there over 90.

 

This is a strange one, I can't believe the pinion angle is that far off.

 

Hey Jared,
I have been following this thread with alot of interest. I am not trying to be a butthead here....I know it's hard to hear my voice since I am typing this. I have never known anyone to have 5-6 driveshafts of different manufacturers and all of them vibrate. You are in a class all to your own now. Second...I know we want our cars to be perfect. But you are tweeking your pinion angle 1 degree at a time to try and stop a vibration that you assume is coming from the driveshaft. So I want to break your focus on it being a driveshaft issue all together. Start looking outside of this box your stuck in. Sypder(Ron) seemed to think about 15 posts back that you found the answer to your issue but you never gave a clear response to his question. Next..this may sound like a stupid question but have you considered the vibration you are feeling at 90mph and above is something else then a driveshaft issue?? Could it be a tire balance issue? An alignment issue? To eliminate all of the possibilites I would install my stock driveshaft back into the car and start from scratch again. After as many DS's as you have had and no one else ever having this kind of issue with an aftermarket DS it is possible that you are focused in the wrong area to fixed your problem. Again I am not being pissey or mean but I have been in your situation over the years with other types of problems and I know how easy it is to get focused on one thing and let the independant thinking stop working. That is my only point with this post. Think about it!!
Scott

 

Interesting.....

 

I'm not trying to sound like an a$$ but I have to ask.
1 Do you have aftermarket rims? (Some are hub centric some aint )
2 Do you have the right lug nuts for them? ( Some rims have a diffrent seat angle )
3 Are you postive its not in the rear end? ( Bearings.crush sleave ,Center section ect.)
4 Do you have any play in the tailshaft of your trans?
5 Is your trans mount bad ?

 

1. no
2. stock
3.yes, this vibration was there with the stock trac-loc and FRPP 4.10 gears with the JPC shaft. I now have a new FRPP 4.10s with a trutrac.
4. no
5. no

 

WOW !! I think I would look at a warped rear end housing or bent axle.

 

no one else having problems with a one piece shaft?

 

Hi Jared,
You haven't been around in awhile .Since you sent our driveshaft back a couple of weeks ago and we gave you a full refund we know that you are not running our driveshaft. Did you reinstall your OEM two-piece shaft? If so, did this eliminate your harmonic vibration? Since your problem we have read on other forums of Mustang owners complaining of harmonic vibrations with afermarket aluminum driveshafts. In all these cases there seems to be other mods that these Mustangs all have in common. 4:10 gears and rigid, racing type suspensions which both create harmonics that the aluminum driveshaft will transmit. The rubber sound deadener inside the OEM two-piece driveshaft does a great job in masking these harmonics. We are currently working on a new aluminum driveshaft that will have a rubber sound deadener inside of it. This shaft will be a trade-off between the heavy two-piece OEM driveshaft and the light-weight one-piece aluminum driveshaft. When we have the prototype ready we will be looking for a "test mule" to test it out. Anyone who currently is having harmonic vibration issues with a aftermarket aluminum driveshaft and would like to be considered PM us.
Robert

 

I picked up some NVH - 63-65 mph - when I had the Spydershaft installed. I took the car out to Ron's shop and he rotated the shaft 180 degrees and that took some of it out. No real vibration, just noise on accel/decel in the 60+ mph range. I'm running stock suspension so there was no reason to change the pinion angle. The only mod I have is the CHE K member with torque limiters. I recedntly added Tokico D Specs and had the strut TSB doen and that seemed to help a little more. After reading other posts it appears that some NVH is going to occur once you remove the stock DS.

 

I would like to clarify what I said in my last post. I'm not saying that these mods are guaranteed to cause NVH. There are plenty of our customers who are lowered with 4:10 gears who are completely satisfied. These mods in our opinion will increase the possibility of NVH. especially the racing type suspension.

 

The N part of NVH is not a big deal and most people won't hear the noise because of their exhaust system. Virbration on the other hand is a problem and should be dealt with before bad things start to happen

 

I know that you feel that way, but believe me when I say there are plenty of people that don't. We manufacture aluminum driveshafts for many different performance applications and we have encountered diiferent groups who are totally against aluminum driveshafts because of urban legends they have read about harmonic vibrations with aluminum driveshafts. We had one performance foreign car forum in which a member was bad mouthing a aluminum driveshaft that they had purchased from a company out west. His complaint was harmonic vibration. We convinced him to try one of ours and we gave it to him at cost. We figured it was good advertising. We install a full length foam insert inside all of our aluminum driveshafts. He was pleasantly surprised to discover that his harmonic vibration was gone after installing our shaft. He sang our praises to his fellow forum members but the urban legend was so ingrained with these guys that most members didn't believe him. To this day we have only sold a handful of these shafts. We gave up and no longer waste any time on that particular forum. We can't force people into believe something that they don't want to.
Robert

 

Just wanted to update, I installed the factory shaft and I have no vibration at all. I do have a spydershaft for sale. I wonder what is going on with some of the s197's? Yeah sure I will test one.

 

This is interesting to me. Review this thread. http://forums.bradbarnett.net/showthread.php?t=470605 Your only modification appears to be 4:10's to the rear end suspension. Many of us with the Spydershaft are having no issues. It is appearing more and more everyday and with every post on 1 pc. driveshafts that rear gear changes and rear end suspension mods may be the cause of vibrations. Interesting....
Scott

 

I have had a number of aftermarket driveshafts trying to get the vibe out (JTGrant, you ain't the only one) -- the best I've done is up to 90 OK, then vibe thereafter. I wonder if all the happy aftermarket driveshaft owners have taken their car over 90 and beyond -- I suspect not.

Pinion angle is important, but I also question the quality of some of the cut down Ranger shafts. I've observed significant runout when running the car on jackstands:

http://www.youtube.com/watch?v=UCU7LsfXMFg

Note - if you want to do this with you car -- BE VERY CAREFUL -- it is dangerous -- don't want to get caught up in a rotating shaft!!!

Based on my experience I would say Caveat Emptor to all who are considering "upgrading" to a one piece shaft.

 

Well the answer is YES but only to 110-115 mph. I wuss out after that. But I still have the totally stock rear suspension. That may be the key!!