Keep breaking wheel studs...

[sixohtofiveoh]

It was the drive shaft causing wheel hop, I installed a factory GT500 drive shaft and ripped a few big burn outs on the street. None of the issues I used to have. My theory is that since my one piece was imbalanced so that when I was loosing traction it was vibrating the rear end like wheel hop. Axle was in perfect shape.

 

[psfracer]

^^^what I don't get is why would it only do it on one side repeatedly. Doesn't make any sense.

 

[RocketcarX]

I don't think it was the driveshaft either ^^^. It pretty much has to be the wheel or the axle. I don't think the street is an accurate test for wheel hop. How do you know the axle was true? have you put the car in the air and watched the wheel roll under engine power while in gear?

 

[sixohtofiveoh]

I don't think it was the driveshaft either ^^^. It pretty much has to be the wheel or the axle. I don't think the street is an accurate test for wheel hop. How do you know the axle was true? have you put the car in the air and watched the wheel roll under engine power while in gear?

I had it on jack stands and it rolled fine, and like I've said it's did it on three sets of wheels. Also for the one wheel things about the way the suspension links into the rear end, the drive shaft and the way the limited slip works. There aren't mounts on the outer most edge of the the axles besides the lca's this allows a certain about of play for the rear end to move upward. A unbalanced drive shaft only spins one way while the car is in drive creating a upward and downward force in that one direction while its spinning, like a person spinning with a weight on a string. That combined with the limited slip locking that wheel up first, you have a recipe for unequal forces acting on one wheel. Like I said, it only broke when I lost traction, not under normal driving conditions. I've gone 10k miles with out a burnout, got a bit loose leaving a light to get on a on ramp. And pow broken wheel stud. Did the same thing, no vibrations over 80 mph like I had before and no broken wheels studs...

 

[Kenaizer]

I had it on jack stands and it rolled fine, and like I've said it's did it on three sets of wheels. Also for the one wheel things about the way the suspension links into the rear end, the drive shaft and the way the limited slip works. There aren't mounts on the outer most edge of the the axles besides the lca's this allows a certain about of play for the rear end to move upward. A unbalanced drive shaft only spins one way while the car is in drive creating a upward and downward force in that one direction while its spinning, like a person spinning with a weight on a string. That combined with the limited slip locking that wheel up first, you have a recipe for unequal forces acting on one wheel. Like I said, it only broke when I lost traction, not under normal driving conditions. I've gone 10k miles with out a burnout, got a bit loose leaving a light to get on a on ramp. And pow broken wheel stud. Did the same thing, no vibrations over 80 mph like I had before and no broken wheels studs...

Hang on, Google is bogging down trying to translate that for me.

 

[fdjizm]

Hang on, Google is bogging down trying to translate that for me.

he said his studs broke again.

 

[sixohtofiveoh]

Basically I did everything that I'd break wheel studs doing before, and I didn't break one. All I did was check for a bent axle and it wasn't bent. Changed the drive shaft did the same things no more broken wheel studs. If you don't understand cool, but like it or not changing the drive shaft fixed it.

 

[stkjock]

so that I understand - you swapped a 1 pc DS for a OEM style DS and you think that has fixed the issue?


if so, IMO, the OEM DS has hidden the underline issue, its dampening benefits have caused the next "phase" of the vibrations to be lessened and the studs not break.

 

[RocketcarX]

so that I understand - you swapped a 1 pc DS for a OEM style DS and you think that has fixed the issue?


if so, IMO, the OEM DS has hidden the underline issue, its dampening benefits have caused the next "phase" of the vibrations to be lessened and the studs not break.

This^^^ I don't believe the car is "fixed".

 

[sixohtofiveoh]

Well there is no long a vibration after 80 miles an hour, I took it all the way up to 130 and there was still no vibration. Normal driving never broke the lug studs, only burnouts or loss of traction. I had 10k miles on the last set of studs, lost traction leaving a light hard once and snapped 3 of them. I feel like if it was an axle it'd happen a lot more, and the axle bearing would be pouring differential oil. I've had this problem since my TR6060 swap at 16k miles, the car now has 40k on it. I feel like after 24k miles with a bent axle, there would be more damage that just breaking lug studs during burnouts.

 

[stkjock]

are you sure it's not wheel hop?

have u upgraded your LCA/UCA?

 

[10seclx]

Going out on a limb here. When you install the new studs are you possibly hammering on them to hard when you pull them through the axle causing them to have stress cracks? I still agree with most I think it's more than likely an axle issue. I put Moser axles in my wife's car. It had a bent axle and she NEVER beats on that car they are shity axles from the factory.

 

[sixohtofiveoh]

I have BMR LCA's but not a UCA. My driveshaft was missing a weight, plus the design wasn't very good. It wasn't a brand name one but one I purchased from a place which I will not name. The CV was in the front, and the yoke would only allow you use four bolts. Like I said before I'm almost sure the unbalanced drive shaft was causing the wheel hop.
I don't hammer studs in, I draw them in using a lug nut and washers. 2011+ Mustangs also come with 31 spline axles so there a bit stronger than previous S197's.

When I say it broke lug studs it was pretty instantaneous, not like it'd break a few miles down the road. Like burn out and you could hear them snapping.

 

[RocketcarX]

I have BMR LCA's but not a UCA. My driveshaft was missing a weight, plus the design wasn't very good. It wasn't a brand name one but one I purchased from a place which I will not name. The CV was in the front, and the yoke would only allow you use four bolts. Like I said before I'm almost sure the unbalanced drive shaft was causing the wheel hop.
I don't hammer studs in, I draw them in using a lug nut and washers. 2011+ Mustangs also come with 31 spline axles so there a bit stronger than previous S197's.

There's your problem. If you are going to draw them in, you need to use the style bearing that is in a power steering installer set up. Combine that with 70 ft-lbs of lug nut torque and that is a recipe for broken when studs.

 

[stkjock]

I have BMR LCA's but not a UCA. My driveshaft was missing a weight, plus the design wasn't very good. It wasn't a brand name one but one I purchased from a place which I will not name. The CV was in the front, and the yoke would only allow you use four bolts. Like I said before I'm almost sure the unbalanced drive shaft was causing the wheel hop.
I don't hammer studs in, I draw them in using a lug nut and washers. 2011+ Mustangs also come with 31 spline axles so there a bit stronger than previous S197's.

31 spline axles have been standard on all s197s

 

[sixohtofiveoh]

I've never seen it done that way, I've always done it the way I've been doing it. Like I said its also on the driver side. I installed the passenger side the same way and they've been fine.

 

[fdjizm]

2011+ Mustangs also come with 31 spline axles so there a bit stronger than previous S197's.

 

[psfracer]

Well, I am not arguing about the driveshaft was responsible--simple fact is if you replaced it and you are no longer shearing studs on that one side, then somehow it corrected the problem. I am just trying to understand the "why", thats all.

In the past when I have seen this problem, it has been either 1) the wrong lug nut used with the wheel, 2) the wheel itself (damaged), 3) the lug nuts backing off, or 4) bent axle. We covered all of the above and eliminated each, so I guess that shows the driveshaft was responsible somehow. I am just confused about the "why".

 

[sixohtofiveoh]

The driver's side is the side that the ring gear is attached to, like I said I think the driveshaft was causing wheel hop and the studs were breaking before the LSD locked up all the way.

 

[psfracer]

^^ yeah I am still not getting it. Are you saying the driveshaft was so out of balance it could cause a rearend that is roughly 190lbs (with gear oil) to hop? I mean, I had an out of balance driveshaft once and it caused a vibration in the seat at 120mph which I felt. Also wheel hop in itself was pretty common in my brothers 2011 when he would gun it from a stop, and he never broke any studs.

When people go to the track and dump the clutch at 6000 rpm to a M/T ET street or whatever, you would think that would put a lot more force on the Wheel/Lug/Stud--but rarely if ever have I seen a 5.0 shear studs at the track.

Like I said it just doesn't add up. But if that is what fixed it then it is what it is.