Detailed discussion on multiple problems!

[Svt_devin]

I'm trying to find someone who knows every aspect of 03-04 cobras to talk to about the problems my car is having. The current topic is my rear end is gear whining louder than it ever has which is my main concern, it also wheel hops and clunks pretty good. All this started after I money shifted from top of 3rd to 2nd and broke the cover which led me to rebuild the rear end with ftbr bushings and ford racing cover. If anyone is interested in having a long detailed convo with me to maybe figure this out id greatly appreciate it. This car has me worried sick right now!

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[P49Y-CY]

C'mon, you can at least post a summary of the problem and then go from there, can't you? There are a lot of people on here who can provide specific details.

 

[Svt_devin]

I agree, I updated the post

 

[BlckBox04]

if the rear is whining and you can confirm it definitely has oil, it's probably not set up with the correct back lash or your pinion angel is wrong.

 

[01yellercobra]

Did you rebuild the center section or just replace the cover? The aluminum bushings transmit more gear noise. If you want it quieter go with poly. As for the clunk, welcome to owning an IRS car. It's the nature of the beast. One of the culprits is the front cradle mount bolts are too small. They need to be replaced with 9/16" bolts (I think).

As for the hop that's another IRS trait. Good springs/shocks can help as well as good tires. IMO you never get it rid of it 100%. I have all of the FTBR bushings, coilovers, and drag radials and it'll still hop once in a while. Depending on where I am.

 

[Comp04svt]

Maybe you could post an in car video so we can hear the noise? Was the ring and pinion rebuilt/replaced, or did you just do the cover and bushings? Did you do the full FTBR kit? What springs and shocks are you running and how many miles on those? What tire are you running out back? Like mentioned above, did you upgrade the cradle bolts?

The FTBR bushings do transmit some gear whine into the car, namely the aluminum front diff bushings. Some cars whine more than others and some claim no additional noise. My car was whisper quiet before I upgraded the bushings/cover, and now some gear noise is present, mainly on cruise and decel. Hasn't really bothered me much to be honest. With the windows down I don't hear anything. Plan to just add some dynomat to the rear seats.

 

[Svt_devin]

if the rear is whining and you can confirm it definitely has oil, it's probably not set up with the correct back lash or your pinion angel is wrong.

I'm almost certain my pinion angle is wrong. I'm going to fix it and check the whine and come back with an update

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[BlckBox04]

I'm almost certain my pinion angle is wrong. I'm going to fix it and check the whine and come back with an update

That'll definitely cause noises

 

[SVT_Troy]

Did you get the milled diff mount with the FTBR kit?


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[Svt_devin]

Did you get the milled diff mount with the FTBR kit?


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Yes

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