Clunk noise in rear end area

[mbsvt]

So Im looking to buy this 03 cobra 80,139 miles
Looks a little rough,but on the test drive, on take off
and on and off the gas and when shifting gears, there is a lot of clunking noise coming from the rear end area.
Humm.....
Any help with this. :shrug: Not normal for sure, but owner was told
all cobras have this issue.
Back lash in rear? IRS busings? Trans?
TKS
MB

 

[icyrolly]

mine has same miles and does the same...im awaiting answers my self

 

[01cobravortech]

FTBR Frequently Asked Questions

We've had the answers for years. You guys just haven't bother to use the search feature on this clunk subject that's been discussed ad nauseum.

 

[perry2k12]

My car does it and the diff bushings are shot. Replacing them this winter because it's more than likely the problem

 

[CobraBob]

As explained in the FTBR FAQs, it could be the rear differential support bushing or the front subframe mounting bolts. And there are solutions to resolve that IF either of those are the issue. It might also be normal play in the drivetrain. .. Clunk Issue

 

[candy3369]

I have this too and it is so annoying. If I baby the car changing gears and give it the perfect amount of gas, I can drive it without doing it.

My dad teaches mechanics at the college and those guys are fixing to do rear ends....he says, "Candy you should let me drive it up there and we can fix it" I'm thinking I don't know about letting college kids learning rear ends even look at my car!!!

 

[Blueline]

There are so many reasons for a clunk in the drivetrain. I re-did my entire rear 40 miles after I bought my car. I did all new gears, bearing etc.... Make sure you check your -U- joints too along with bushings etc. After I finished my rebuild I have absolutely NO play in my drivetrain. When I shift gears or start from a stop its smooth as butter. As far as bushings, I have poly bushings throughout the entire rear, these were installed by the previous owner. When I put my car on the lift, I could spin my driveshaft about 1/4 -1/2 turn before the pinion started moving the ring gear. My rear was completely shot, not saying thats your problem, but get under there and start looking at things. Good luck!

 

[candy3369]

Just called my uncle who is a Ford mechanic, owns a 70 Mustang 351 Stroker that he did a complete rotisserie on, he said bring it to him and he will fix it for me. I will let him look at it before I buy any parts. Lucky for me my whole family is in cars because I see this getting expensive at the Ford dealership!

 

[icyrolly]

FTBR Frequently Asked Questions

We've had the answers for years. You guys just haven't bother to use the search feature on this clunk subject that's been discussed ad nauseum.

i know what the answers are...just not enthused about laying on a creeper for hours to fix...i got new pinion support bushings from steeda, going to start there...

 

[Mystic03]

be sure the rear irs bracket is snugged they tend to shake loose and definetly will be obnoxious when taking off loud clunking

 

[TRBO VNM]

mine has same miles and does the same...im awaiting answers my self

i know what the answers are...just not enthused about laying on a creeper for hours to fix...i got new pinion support bushings from steeda, going to start there...

:shrug:

 

[keith89]

On top of the bushings, it could be the backlash has loosened up. The IRS pinion depth needs to be set up with a solid spacer instead of a crush sleeve. I believe this is the issue I'm having now. When I had my 3.73's installed, it was fine, but a few months later i started getting a clunk and i noticed i could move my driveshaft a good amount without the axles turning. I've been driving around the issue right now but I'll have to drop the diff again eventually and will probably go with 3.27's and have the pinion set up with a solid spacer.

 

[Blueline]

Keith who does your rears? I have a great guy in northern NJ.

 

[keith89]

Keith who does your rears? I have a great guy in northern NJ.

I'm actually looking for someone to do it or try it myself. They were done a few years ago when Travis and Frank were at Difeo Ford. I was told it is normal but I'd rather have it checked again since it was fine for a few months. There's a good 10-15 degrees of play in the driveshaft without the axles moving. In stop and go traffic, the driveshaft will just bounce back and forth if i'm not careful with the clutch. It's pretty annoying.

 

[Blueline]

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