REAR END NOISE 2004 Mach 1

[xXDSGMach1Xx]

Hey guys I recently bought a 2004 Mach 1 with 4,800 miles on it. I drove it 10 miles from the dealer and had a clunking/grinding noise in the rear end. ( mostly while turning.) I took the car back and they changed the fluids (2 times now). I get the car back both times still doing it. I have noticed it does it after you drive it 10-20 miles. It gets bad enough that feels like the rear axle is hopping. The car is 100% stock with the 3.55s from factory. I just dropped the car off again, very unhappy about this. Do you guys have any ideas? email me if you want [email protected]

 

[trinity_gt]

The limited slip differential is likely the source of the problem. When the fluid was changed was a bottle of friction modifier added (or was a fluid with the additive already present used)?

4800 miles? That's it? You might just drive around with it for a few hundred miles to blow the cobwebs out of it...

 

[xXDSGMach1Xx]

The dealers service manager said they used Fluid with the modifier in it. I just picked it up an hour ago and noise is still there. I am completely disgusted with this now. Ha yeah it only has 4,884 miles

 

[twogts4us]

I'm really saddened to hear your dilemma. This just isn't right. Did you buy it from the dealership that has been trying to fix it? If so, you have leverage.

 

[xXDSGMach1Xx]

no its not right ha really sucks. I did buy it from a dealer. I have had the car for 20 days and its been back to them 4 times. The last time at the shop they told me they thought it was the brake calipers (DUMB). Now its not a Ford dealers it is a Cadillac dealer but still...

 

[jetmech807]

An 8 year old car with just shy of 5000 miles has sat......a lot. Not good. In the right environment could have had some condensation form in the housing maybe or driven through or sat in water at some point. Either way, maybe some water has got in there and corroded the axle/carrier/pinion bearings a bit.

Sent from my PC36100 using Tapatalk

 

[twogts4us]

Yeah it sounds to me that they will have to pull the rear end apart to diagnose the issue. Did it have a clear title? (not salvage)

 

[xXDSGMach1Xx]

clear title.. 1 owner ( a woman ). dealership called today. They say its the clutches and they say they are not paying full.. they want me to pay 50%... I bought the car drove 10 miles and this issue appeared.. Should I be paying for it?

 

[Black'02]

I agree, it sounds like the clutches in the limited slip. I dont think you should be paying for it, I noticed that when mine had the same issue it wouldnt start unless the rear end was sufficiently warmed up as well. It sounds like they sold it to you with this problem. Good luck getting it fixed, sounds like it's a really nice car once that gets squared away.

 

[xXDSGMach1Xx]

I can't blame the dealer for knowing the problem. I pretty much bought it the day they got it in. I bought it and wouldn't even let them clean it. Didn't want some kid trying to buff it for some reason and messing up the paint. So I can't point fingers and say they knew. But I can say they should take care of it.

 

[xXDSGMach1Xx]

I also noticed today it gets a lot worse as the rear end gets warmer. and if i do circles ( because thats the only time it does it ) it will not make an noises with the clutch pushed in. release the clutch after coasting the noises come back.

 

[Bob Cutts]

Thanks jfisher for bringing up this problem and your email responses. Here are my results. It is the clutch pack in the differential see Technical Service Bulletin. My car noise was described as a moan by the dealer.

TSB
04-24-20 LIMITED SLIP AXLE CHATTER, SHUDDER, BINDING SENSATION, OR VIBRATION DURING LOW SPEED TURNING MANEUVERS

Publication Date: November 30, 2004

Thanks,
Mach1bob

PS They have to replace the differential assembly, around $2000