What Is The Diagnosis

[wells1989]

1990 fox with 56k. Only mods are cat back exhaust, ram air cervinis kit, 17x9 cobra r, maximum motorsport sport strut tower, k-member, and frame connectors.
The car does a lot of sitting especially the last few years. Last thing i did last August was put the chasis stiffening parts on. I drove it 1 time in September and it sat until last night. I drove about 10 miles and when i entered a parking lot i noticed a moaning, squeaky like chatter. I originally thought it was something clutch related. A few more miles around town and i am thinking maybe my rear end. It only makes the noise at slow speeds and when turning.

Can anyone please give me advice and also school me on what type of rear end is in a fox and how it works.

My buddy had an 04 mach 1 with 3k miles on it that did this. He was told the clutches dried out from setting?

Ps the posi is still working!!

 

[stykthyn]

I would put money on your control arm bushings making the noise before your clutches. If you've strengthened the frame you're making your rear arms work that much harder.

 

[Davedacarpainter]

Your rear end is an 8.8" (that is the size of the ring gear on your diff. btw). it uses a traklock differential. You'll either have 2.73 or the optional 3.08 gears. 28 spline c-clip axles. Drum brakes. 4 lug hub.

 

[A5literMan]

Also it could be the driveshaft. Put it on jackstands with someone in the car. Lie beside the car while they put it in gear and let the clutch out. Just to get everything in motion. See if you can isolate where the notice is coming from.

 

[stykthyn]

Also it could be the driveshaft. Put it on jackstands with someone in the car. Lie beside the car while they put it in gear and let the clutch out. Just to get everything in motion. See if you can isolate where the notice is coming from.

My experience, and I could be wrong, is that unsprung suspension will not duplicate the same results. Off the ground one tire will spin faster than the other and both tires will likely exhibit a good amount of oscillation. The drive shaft angle changes dramatically which also influences results there as well.

My gut is really leaning towards bushings. The fact that it's more noticeable during a turn especially at low speed is my biggest tip off in this situation.

 

[A5literMan]

My experience, and I could be wrong, is that unsprung suspension will not duplicate the same results. Off the ground one tire will spin faster than the other and both tires will likely exhibit a good amount of oscillation. The drive shaft angle changes dramatically which also influences results there as well.

My gut is really leaning towards bushings. The fact that it's more noticeable during a turn especially at low speed is my biggest tip off in this situation.

Agree with you. That makes sense. I will say though if a u joint is going bad they will still squeak without suspension load etc.

 

[89oem]

Like above somewhere in the suspension, use will get it to mellow, go away, or tell you exactly whats going out.

Rear, you can spin the wheel and count axle revolutions or easier; read the tag on the differential 2L73 (2.73) or 3L08 (3.08). You can also tell the original gears if the driver door data tag is still there. Under AX will be a code. M=2.73 and Z=3.08. All GT's and 5.0L LX's came with traction loc

 

[wells1989]

I know my car has 3.08 gears based on the doort tag. I took it for another spin yesterday and tried to recreate the noise that was so awful the night before. I was able to make it happen but it was way less noticable. I drove in circles in an intersection.

 

[Boosted92LX]

A traction lock diff that has had the oil changed, but no friction modifier added for the clutches will behave EXACTLY like you are describing. Been there. Done that.

I don't use lube shops anymore.

 

[wells1989]

Considering i have not had my rear diff oil changed in the 10 years i have owned the car and assuming it was never changed prior to that either could this be the problem? Also the fact that my car sat 7 months with out moving would have left the clutches to dry out. My question is will they quite down if i change the lube or is it time to do a rebuild and put in 355s or 373. It would be ashame to not change the gear if i was already in there

 

[Boosted92LX]

Considering i have not had my rear diff oil changed in the 10 years i have owned the car and assuming it was never changed prior to that either could this be the problem? Also the fact that my car sat 7 months with out moving would have left the clutches to dry out. My question is will they quite down if i change the lube or is it time to do a rebuild and put in 355s or 373. It would be ashame to not change the gear if i was already in there

Well, has it been leaking? Are you sure it even has oil in it?

 

[Boosted92LX]

I'd pull the plug and stick something in to see if you have a level.

 

[wells1989]

Def not leaking and has not leaked a drop in the 10 years i have owned it.

 

[Boosted92LX]

Def not leaking and has not leaked a drop in the 10 years i have owned it.

Maybe you have a carrier baering or a wheel bearing crapping out. Wouldn't hurt to do an inspection and oil change.