Drive train noise from the rearend...

[BYRDPE]

I am having an intermit popping noise coming from the drivetrain. It usually happens after I shift and let out the clutch. It doesn't do it every time but it's seems like it's starting to get worse. Today I jacked up the front and rear to inspect the motormounts, drive shaft, u-joints and the tranny mount and they are all in good shape. While I had it up I decided to run it through the gears to see if I could pinpoint the noise. I put it in 1st and let out the clutch and then when I put it in
2nd and popped the clutch and I could hear that the sound was coming from the rear end.
Any idea what could be amiss in there? It's a metal to metal sound.
BTW....I also checked the fluid level in the diff and it is full.
Thanks

 

[white99gt]

Have you checked the upper axle bushings?They will get worn and cause a pop noise because they will get worn enough to hit the mounting ring.

 

[BYRDPE]

Have you checked the upper axle bushings?They will get worn and cause a pop noise because they will get worn enough to hit the mounting ring.

Hmm...they looked fine when I replaced the uppers with FRP HD uppers.
I'll have to recheck them.
Come to think of it I didn't notice any of this noise until I replaced the uppers and the rear end cover.

 

[white99gt]

Hmm...they looked fine when I replaced the uppers with FRP HD uppers.
I'll have to recheck them.
Come to think of it I didn't notice any of this noise until I replaced the uppers and the rear end cover.

You installed the hd uppers without the bushings?
DId you torque them up in the air or with the car sitting on the suspension?
It could have helped finish off the bushings if they were torqued will the rear end was hanging.

 

[BYRDPE]

You installed the hd uppers without the bushings?
DId you torque them up in the air or with the car sitting on the suspension?
It could have helped finish off the bushings if they were torqued will the rear end was hanging.

Yes I did install them without changing the bushings cause they looked fine. And yes the car was on jack stands when I torqued the down.
I have an aluminum DS and the metal to metal sound sounds like metal on aluminum. The DS was the first thing I checked because of the sound of metal hitting aluminum.
I still could hear the noise even with the suspension unloaded.

 

[white99gt]

Yes I did install them without changing the bushings cause they looked fine. And yes the car was on jack stands when I torqued the down.
I have an aluminum DS and the metal to metal sound sounds like metal on aluminum. The DS was the first thing I checked because of the sound of metal hitting aluminum.
I still could hear the noise even with the suspension unloaded.

How many miles on them(stock bushings).Mine "looked" ok at 200k but when i applied pressure(screw driver in the bolt hole).I could see the cracks in the bushings).

what type of rear cover did you install?

 

[BYRDPE]

How many miles on them(stock bushings).Mine "looked" ok at 200k but when i applied pressure(screw driver in the bolt hole).I could see the cracks in the bushings).

what type of rear cover did you install?

Mac rear cover.
I'll remove the uppers and check the bushings to rule the out or change them.
They have 92K miles on them.

 

[white99gt]

Mac rear cover.
I'll remove the uppers and check the bushings to rule the out or change them.
They have 92K miles on them.

92k plus the age of the car.I would replace them ,im betting they are shot.

The mac cover have the cap bolts? How tight were the bolts torqued for the caps?

 

[BYRDPE]

92k plus the age of the car.I would replace them ,im betting they are shot.

The mac cover have the cap bolts? How tight were the bolts torqued for the caps?

I don't remember the torque settings but I just locked the nuts after the screws made contact.
I also loosened them up entirely to rule them out.

 

[Fox8950]

The rear end gears I have are kind of sloppy and after the aluminum drive shaft went on, it turned into a giant microphone for the clunk sound they made every so often. Time for a rebuild here not sure if thats even close to what you are hearing just a thought.

 

[BYRDPE]

The rear end gears I have are kind of sloppy and after the aluminum drive shaft went on, it turned into a giant microphone for the clunk sound they made every so often. Time for a rebuild here not sure if thats even close to what you are hearing just a thought.

Thanks for the reply.
I'm going to get her back up in the air and have a buddy run it through the gears while I listen.
Hopefully I can pinpoint the issue.

 

[Mr Grim]

The stock bushings use a steel sleeve with serrations on both ends, to help the bushing seat to the bracket. Aftermarket bushings usually don't have the serrations, allowing the bushing to slide slightly as you accel and decel. I had to use an impact to get the arms tight enough not to pop. You might be able to look around the edge of the bushings to see if there is any signs of movement.
OK, I just saw that you are using the stock bushings....I would still check for movement there.

 

[PUNISHER RACING]

is your d/s hitting the e-brake cable?

 

[BYRDPE]

The stock bushings use a steel sleeve with serrations on both ends, to help the bushing seat to the bracket. Aftermarket bushings usually don't have the serrations, allowing the bushing to slide slightly as you accel and decel. I had to use an impact to get the arms tight enough not to pop. You might be able to look around the edge of the bushings to see if there is any signs of movement.
OK, I just saw that you are using the stock bushings....I would still check for movement there.

I'll definitely check this out.

is your d/s hitting the e-brake cable?

It wasn't when I had it on the stands.
If this was happening I believe the sound would be continueous.
I'ts definitely involving the DS cause I can hear the aluminum hitting metal sound.
What about the pinion flange? Could anything be checked there?