Newer 5th Gen Owner Rear End Noise

[2011SS2SS]

OK. I got the car in Feb. It is a 2011 Camaro 6 speed 2SS. The only mod for the time being is a CAI.

When I got the car the rear end was louder than I expected. However, I did not notice it as much w/the radio blaring & exhaust being pretty loud. The other day I took it out & had the AC off, radio down, & was coasting through a parking lot. It sounds like I can hear the teeth of the gears connecting at low speed.

It is whining when I am going slower down the road. Not extremely loud, but it has been like this for a while now. So, I decided to change the diff fluid. I put in Royal Purple 75-90 which is the weight the manual calls for. I also put in the friction modifier the book calls for...

Still loud & seems to have added a chatter... Although I must be honest; I may have moved something on the exhaust causing the chatter as it was closer to the drain than I expected...

My questions: Are the rear ends in these cars louder than most?? I think I know what's ahead & am dreading it bigger than crap. ANY advice is appreciated.

[Rock-It Man]

No, not loud.

Some people have experienced a groan during slow speed tight turns, particularly when cold and/or in reverse. This can be reduced by changing the fluid and using the correct friction modifier, but it is an inherent characteristic of limited slip differential and cannot be entirely eliminated. It's harmless.

On the other hand, whining or chattering gears are a sign of excessive backlash, which could be caused by either wear or poor setup when installing new gears.

[2011SS2SS]

Originally Posted by Rock-It Man

No, not loud.

Some people have experienced a groan during slow speed tight turns, particularly when cold and/or in reverse. This can be reduced by changing the fluid and using the correct friction modifier, but it is an inherent characteristic of limited slip differential and cannot be entirely eliminated. It's harmless.

On the other hand, whining or chattering gears are a sign of excessive backlash, which could be caused by either wear or poor setup when installing new gears.

It only has 50k miles on it & I have not changed the gears... It seems like the stock ratio as well. Seems like it is pretty early to have a gear failure as I am not extremely hard on it... Wish I could get a video of the noise, but that would be hard to do...

[Camaro__ss]

It might be a wheel bearing. See if it goes away when you exert lateral force by swerving at high speed, either direction. A wheel hub bearing will go away for a second as it is unloaded. That was my experience.

[pnwdan]

RP Max Gear 75w90 has friction modifier in it already.

That being said, are you sure it's the rear end and not the tires or something else? These cars are loud in the back due to not having any sound deadening back there.

[InFiD3ViL]

Not trying to be a smart ass, but there is such a thing as too much friction modifier. As pnwdan said, RP already has it mixed in.

['10CamaroDude]

If it is a GROWLING noise, it's probably your wheel bearings, but to continue:

Differentials will whine when the gears wear, or pinion preload loosens up. You should
not hear the teeth meshing, unless there is no oil in the differential. Gear grinding
will present itself as a humming noise. I am willing to bet it's a wheel bearing.

The pinion, and carrier ride on bearings too, so if a bearing is failing inside the
differential the noise is virtually the same as the one created by a failing wheel
bearing making it hard to isolate.

If it is a wheel bearing, turns will change the volume of the growling. So, if you're
on the highway, and no one is around, weave in and out of the lanes, and listen.
Of the growling changes, it's a wheel bearing.

[2011SS2SS]

Originally Posted by '10CamaroDude

If it is a GROWLING noise, it's probably your wheel bearings, but to continue:

Differentials will whine when the gears wear, or pinion preload loosens up. You should
not hear the teeth meshing, unless there is no oil in the differential. Gear grinding
will present itself as a humming noise. I am willing to bet it's a wheel bearing.

The pinion, and carrier ride on bearings too, so if a bearing is failing inside the
differential the noise is virtually the same as the one created by a failing wheel
bearing making it hard to isolate.

If it is a wheel bearing, turns will change the volume of the growling. So, if you're
on the highway, and no one is around, weave in and out of the lanes, and listen.
Of the growling changes, it's a wheel bearing.

This actually makes sense...

I will try it tomorrow if it doesn't storm as the weather is saying.

As for the Additive comments... I wasn't aware Royal Purple had additive in it... Should've paid more attention. I may try draining it & refilling w/just Royal Purple. Not sure it matters much TBH tho. The fluid change didn't change the noise. There is a chatter, but I am not sure it wasn't there to begin with... Thanks for the advice guys; at least I have a direction to head/things to try...

[Rock-It Man]

Originally Posted by 2011SS2SS

This actually makes sense...

I will try it tomorrow if it doesn't storm as the weather is saying.

As for the Additive comments... I wasn't aware Royal Purple had additive in it... Should've paid more attention. I may try draining it & refilling w/just Royal Purple. Not sure it matters much TBH tho. The fluid change didn't change the noise. There is a chatter, but I am not sure it wasn't there to begin with... Thanks for the advice guys; at least I have a direction to head/things to try...

If you use the Delco oil that is specified for LSD, which does have friction modifier, you still need the additional friction modifier for the Camaro. This is all spelled out in the owners manual. At some point in Gen 5, both part numbers were superseded, but this is easy to track down. Just go to Summit Racing and input the numbers in your OM. If superseded, the new ones will show up in your search. Don't have the OM? You can download it from the Chevy website.

It's not rocker science.

As for Royal Purple, people have reported mixed results using it with no modifier.

Personally, I stick with all the fluids specified by GM engineers because I'm an engineer too.

['10CamaroDude]

Right, the same GM "Engineers" for the breaking blend-door, because the motor
moves beyond the stop point of the door, and twists it apart... The same
"Engineers" that made the PCV orifices too small, realize it later after oil leak
complaints, and updated the part. The SAME "Engineers" responsible for LLT timing
chain failures... The same "Engineers" for the oil consumption in the V6, through the
PCV system, then updated the RH valve cover gasket after all the engine failures due to
low oil.

THOSE "ENGINEERS?"

Oh....

[Silveradoss573]

I used gm #88862624 diff fluid which already has the modifier in it. Seen a lot of people in previous threads have issues with royal purple. I too was looking at running royal purple before I saw all the complaints. My rear diff is nice and quiet and no chatter as if yet.

[Rock-It Man]

Originally Posted by Silveradoss573

I used gm #88862624 diff fluid which already has the modifier in it. Seen a lot of people in previous threads have issues with royal purple. I too was looking at running royal purple before I saw all the complaints. My rear diff is nice and quiet and no chatter as if yet.

How long ago did you put this in?

This is the correct diff fluid for Gen 6. I've read that it may be incompatible with the seals in Gen 5 rear ends, but would love to hear otherwise.

[Silveradoss573]

Originally Posted by Rock-It Man

How long ago did you put this in?

This is the correct diff fluid for Gen 6. I've read that it may be incompatible with the seals in Gen 5 rear ends, but would love to hear otherwise.

I drained and filled the diff shortly after I bought the car almost 2 years ago. I was messaged by a few on here and was told by my dealer as well that it's compatible and safe to use. That's all I had to go on at the time other than a few threads I came across on here. I mean so far no leaks or anything. Now I will admit I don't drive it much though.

[gsxrturbo]

DOES yr diff have aftermarket bushings,like hard poly.It will make yr diff seem alot louder