Trying to fix vibe.. what do they replace in the rear?

[RJCobra]

new tires

 

[svt1.8t]

i have brand new eagle f1 gsd3 on 18 black fr500 wheels, i've had the shake since i drove it home from the dealer

 

[MY DREAM]

Alright every one, I have some info that might be usefull. I have had my drive shaft replaced and my tires balanced with no luck of the vibe going away. The other day, I dont know why but at 85mph I pushed in the clutch and the vibe went away. So I tried it at all different speeds that the vibe occures at, and every time I pushed in the clutch it went away. That right thier would tell me that from the drive shaft back to the rear wheels everything is good cause with the clutch pushed in, from the drive shaft back everything is still turning the same speed as before. Now when you do this the clutch will slow down and the engine RPM will also slow down. Does anyone think that this could be a clutch prob? I just wanted to get the word out so that anyone with the prob could try pushing in thier clutch while the vibe is pressent to see if it go's away. This could help narrow the prob down for some folks. I will be taking Cobra in this weekend to see what they can find out.

James

 

[03soniccobra01]

OK...after two driveshafts, two rear ends, New Halfshafts and hubs, New rear bushings. My vibe is gone. Get this.....The first time I noticed it was after the new rear end. I got a new one because of the slop in the rear.(Lost cause)...Anyway the input flange on the diff was slightly TWISTED? Just enough to throw everything out of balance. Could not believe it! No vide for me now!!!!! My dealer is the best in the southwest. They always take care of me well! :thumbsup:

 

[hmwave]

So I tried it at all different speeds that the vibe occures at, and every time I pushed in the clutch it went away. That right thier would tell me that from the drive shaft back to the rear wheels everything is good cause with the clutch pushed in, from the drive shaft back everything is still turning the same speed as before. Now when you do this the clutch will slow down and the engine RPM will also slow down. Does anyone think that this could be a clutch prob?
James

Mine does exactly the same.

However the vibe going away with the clutch down does not mean there is nothing wrong in the driveshaft, diff etc. No-load vibration (or lack of it) is not the same as load vibration as any worn bushings or u-joints under load can cause a vibe.

A better test is to roll along a flat road in calm conditions, accelerate lightly to the 'vibe speed', then let off the gas pedal to see if the vibe goes away. Even then, if the vibe lessens, it could still be any worn or out of balance part in the driveline.

My drag racing friend tells me the symptoms on my car point to worn u-joints. I'll check with the dealer to make sure they were replaced last time they tried to fix the vibe. They are trying again soon.

I have a new Fidanza wheel and CF DF going in soon so I'll let you know if that makes any difference to the vibe.

The only real way to find the cause is to put the EARS on the car and methodically find the vibe source then replace/fix parts to eliminate it. That can be a time consuming process so dealers may be reluctant to do that if Ford won't pay them the shop time (even it it leaves you an unhappy customer).

 

[03 DSG Snake]

I've had my original driveshaft taken out and balanced at a drivetrain shop as well as putting in a newer part # from the 04 Cobra. Mine also lessens greatly with the clutch being pressed in at highway speeds... GRRR :fm:

 

[drkchk03svt]

Well after calling MM and talking to a friend of mine they both tell me the same thing. My swaying is with out a doubt coming from bad bushings. I guess that is my next step.

 

[hmwave]

Well after calling MM and talking to a friend of mine they both tell me the same thing. My swaying is with out a doubt coming from bad bushings. I guess that is my next step.

Bad stock bushings?

 

[Chucko]

a ford powertrain tech told me that the problem occurs because of the pinion angle is in-correct ..... in first and second they is sufficient torque to compress the bushings in the irs dif ... but once you shift into 3,4,5,6, the vibration starts ... you what is needed is to add shims,washers etc between the irs and the irs brace/ remove, trim the bushing between the irs dif and the cage .... the front of the dif needs to be raised to correct the problem

once you put the car in nuetral and the vibration stops then the problem is your clutch or tranny

I've been slowly coming to the same conclusion myself. I've read many threads here and elsewhere that shows that the differential bushings are too compliant allowing the pinion angle to be incorrect under certain loading conditions, not to mention that the pinion angle may be incorrectly adjusted in the first place.

Seems like the best solution is to use the MM Aluminum Diff Bushing Kit (found here) and get the pinion angle adjusted properly and solve the problem once and for all.

 

[drkchk03svt]

Bad stock bushings?

It could be stock or aftermarket. A cracked bushing would cause swaying in the rear end under power.

 

[redstaf426]

Balanced my drive shaft at local rear end shop($70),vibe is gone Completely.My vibe was really really bad,too.It physically felt exactly like wheel hopping at 120 mph,felt like my rear end is going to fly off under my car..I didn't take it back to the dealer because I figure if the stock drive shaft is off balanced,why would a replacement drive shaft from Ford be balanced?I mean it is manufactured,and balanced,by the same people....

 

[crimecrusher]

I've had this vibe fixed 4 times so far with tire balancing, 2 new drive shafts and a new rear end. Each time it comes back and then I was told it was the tires. Now I have new tires and the vibe is still there. The car has been at the dealer for two weeks and I'm being told they are putting in a new drive shaft "again." Could this be the transmission?

What is the buy back policy? I want to keep the car unless I get a new shelby GT500 next year.

 

[hmwave]

Mine does exactly the same.

However the vibe going away with the clutch down does not mean there is nothing wrong in the driveshaft, diff etc. No-load vibration (or lack of it) is not the same as load vibration as any worn bushings or u-joints under load can cause a vibe.

A better test is to roll along a flat road in calm conditions, accelerate lightly to the 'vibe speed', then let off the gas pedal to see if the vibe goes away. Even then, if the vibe lessens, it could still be any worn or out of balance part in the driveline.

My drag racing friend tells me the symptoms on my car point to worn u-joints. I'll check with the dealer to make sure they were replaced last time they tried to fix the vibe. They are trying again soon.

I have a new Fidanza wheel and CF DF going in soon so I'll let you know if that makes any difference to the vibe.

The only real way to find the cause is to put the EARS on the car and methodically find the vibe source then replace/fix parts to eliminate it. That can be a time consuming process so dealers may be reluctant to do that if Ford won't pay them the shop time (even it it leaves you an unhappy customer).

The CF DF and Fidanza are now on the car and pretty much ALL of my vibe has gone especially the one around 2000rpm.
The tech found that a roller needle in the pilot bearing was missing so that might have been the vibe problem with mine.

 

[Nysbadmk8]

Ford quality.... Im having all these issues too. Seat belt retractor, Vibration At 60mph+ Steering wheel sqeek, stalling... god... anything else?

edit.. I have TOB issues too! Fun stuff

 

[hmwave]

Ford quality.... Im having all these issues too. Seat belt retractor, Vibration At 60mph+ Steering wheel sqeek, stalling... god... anything else?

edit.. I have TOB issues too! Fun stuff

What kind of vibe at 60+, steering wheel?

My steering creak has FINALLY been fixed. My tech tack welded the front LCA pin and the creaking has gone!

Stalling requires a new flash.