Rear axles stability

PonyGTrider

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Good morning all,
Just wondering if anybody has any knowledge or if it is possible to maintain the axles from moving up and down at the splines side (Inside the differential) it is annoying the bumping noise of the axles playing around.

Or if that noise is an indication of excessive play on the side gears.
I have a Detroit trutrack differential with 3:55 gears and 31 splines moser axles.

Ana ideas if bearings can be adapted to the rear axle inner tubes close to the differential to maintain the axles trueness.

Axial play (In and out) is not the issue and no other noises coming from the rear end.

Please feel free to comment, thanks a bunch
 
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91TwighlightGT

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I think it is your differential...

 
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PonyGTrider

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I think it is your differential...

I think it is your differential...

I
I think it is your differential...


Thanks man!
I read that thread and somethings make sense while others don't but I will look into it.
My main issue is not chattering but instead bumping noise and with the car standing I grab any rear tire from the top and start rocking it in and out the tip of the axle (Where the splines are) moves up and down. is there a way to adjust such excessive play? It seems and feels like the side gears have too much play in their bores...
Is there any remedy to at least reduce or limit that unwanted movement to keep the axles more stable?
 

PonyGTrider

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I am not sure, but maybe these would solve it?


Those C clips eliminators will take care of any axial play but the in the end of the axles inside the differential will stay the same.
I will have to open the differential and inspect the side gears for possible excessive wear inside the bores. That definitely would play a role on the issue I’m having.
So let me ask, the spline that engage the carrier has movement?
 

PonyGTrider

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So let me ask, the spline that engage the carrier has movement?

That I don’t know I haven’t open the differential yet. When do that I will proceed to inspect splines/side gears fitment or possible wear in the carrier bores where the side gears ride in. I’m not sure what else could be the root of my issues.(Maybe Tun a heavier gear oil? I just don’t know what else to do
 

WhiteCobra95

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For clarity, what are you doing to assess this play? Is this from rotating the axle or tire? Or is is this from pushing and pulling the axle against the carrier?

If it's from rotation, you could have too much lash between the ring and pinion. This means that your gears weren't shimmed correctly. Usually this results in a big clunk when you tip in and out of the gas pedal while cruising. In this scenario the driveline winds up in different directions between coasting and applying positive torque to the rear axle. When you change directions, the added lash in the rear end allows the gears to slap and you get that clunk sound. This can also be caused by bad u-joints.
 
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PonyGTrider

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For clarity, what are you doing to assess this play? Is this from rotating the axle or tire? Or is is this from pushing and pulling the axle against the carrier?

If it's from rotation, you could have too much lash between the ring and pinion. This means that your gears weren't shimmed correctly. Usually this results in a big clunk when you tip in and out of the gas pedal while cruising. In this scenario the driveline winds up in different directions between coasting and applying positive torque to the rear axle. When you change directions, the added lash in the rear end allows the gears to slap and you get that clunk sound. This can also be caused by bad u-joints.
 

PonyGTrider

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None of that,
Axles in and out (Axial play) don’t have that.
Rotational play(Backlash) don’t have that.
If your car is standing, go and stick both hands over a rear tire grab the tire from the inside pull it hard and try to rock the car from that point and you will feel the axle moving up and down. In my case I feel it moves a bit too much, and it sounds like bumping specially when going over a rough street.
 

General karthief

wonder how much it would cost to ship you a pair
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If you are rocking the car like you described (rear tires on the ground) and there is a slight clunking noise I believe that to be normal, if the gears in the rear had any up and down play at that end of the axle, where the spline engages the spider gears or up and down movement in the spider gears I think it would be whining like a big dog.
You can pull the rear cover and inspect it really easily, if it has never been off now is a good time to change the fluid anyway.
DISCLAIMER: this is my opinion and not based on any actual mechanical experience. :jester:
 

PonyGTrider

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If you are rocking the car like you described (rear tires on the ground) and there is a slight clunking noise I believe that to be normal, if the gears in the rear had any up and down play at that end of the axle, where the spline engages the spider gears or up and down movement in the spider gears I think it would be whining like a big dog.
You can pull the rear cover and inspect it really easily, if it has never been off now is a good time to change the fluid anyway.
DISCLAIMER: this is my opinion and not based on any actual mechanical experience. :jester:
If you are rocking the car like you described (rear tires on the ground) and there is a slight clunking noise I believe that to be normal, if the gears in the rear had any up and down play at that end of the axle, where the spline engages the spider gears or up and down movement in the spider gears I think it would be whining like a big dog.
You can pull the rear cover and inspect it really easily, if it has never been off now is a good time to change the fluid anyway.
DISCLAIMER: this is my opinion and not based on any actual mechanical experience. :jester:

I feel that axle tip moving up and down but I hear no whining noises and the bumping noise happens only when driving on a bumpy road. I still have no chance to open the rear end to inspect it for any abnormalities.
 

revhead347

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Someone was mentioning the C-clips in the link. There was talk about some spacer etc. That's why I brought it up. I hope my Truetrac doesn't make noise when it shows up.

Kurt
 
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PonyGTrider

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Someone was mentioning the C-clips in the link. There was talk about some spacer etc. That's why I brought it up. I hope my Truetrac doesn't make noise when it shows up.

Kurt

You will be happy with it has been quiet since I installed it, very comfortable. It’s just that noise that I will have to find where’s coming from
I would love to use a spool but it is almost prohibited for a DD in a parking lot

Like anything else the truetrac has its limits on power handling (Which I don’t know the spec)

I’ve been happy for the most part of it.
 

revhead347

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You will be happy with it has been quiet since I installed it, very comfortable. It’s just that noise that I will have to find where’s coming from
I would love to use a spool but it is almost prohibited for a DD in a parking lot

Like anything else the truetrac has its limits on power handling (Which I don’t know the spec)

I’ve been happy for the most part of it.

My buddy has one in his 9 second Mustang, and says it works flawlessly. I am trying to avoid a spool. This is going in my 33 spline braced axle with 9" ends, not C-clip eliminators.

Kurt
 
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7991LXnSHO

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From the Eaton site -
How much horsepower and torque will the Truetrac handle?
Detroit Truetrac is designed to handle more torque (power) than the axle shafts it drives. Horsepower has little influence on the differential since it is more of a function of engine RPM. Each model of Truetrac is designed to unique torque capacity specifications; however, they are all developed to handle the extreme torque loads typical in professional racing and military applications. The torque limit is largely limited by the “barrel” diameter (the inside diameter of the ring gear) but is also limited in c-clip models by the reduced pinion gear sets due to the c-clip installation pocket. Since these parameters are dictated by the axle design and ring gear strength, the Truetrac differential should not be the limiting component in the axle’s torque capacity.
 

PonyGTrider

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My buddy has one in his 9 second Mustang, and says it works flawlessly. I am trying to avoid a spool. This is going in my 33 spline braced axle with 9" ends, not C-clip eliminators.

Kurt

There you have it, like I said you will be happy. You need a good power for 9 secs, that means that differential handles it very good.

Maybe I’m having problems somewhere else because My has no whining, vibration or things like that just no noises.

Good luck to you!
 

PonyGTrider

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From the Eaton site -
How much horsepower and torque will the Truetrac handle?
Detroit Truetrac is designed to handle more torque (power) than the axle shafts it drives. Horsepower has little influence on the differential since it is more of a function of engine RPM. Each model of Truetrac is designed to unique torque capacity specifications; however, they are all developed to handle the extreme torque loads typical in professional racing and military applications. The torque limit is largely limited by the “barrel” diameter (the inside diameter of the ring gear) but is also limited in c-clip models by the reduced pinion gear sets due to the c-clip installation pocket. Since these parameters are dictated by the axle design and ring gear strength, the Truetrac differential should not be the limiting component in the axle’s torque capacity.

Excellent and helpful information you shared. Thank you much :)