Dana s60 rear end noise
08-28-2015, 09:48 PM
#1
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Dana s60 rear end noise
Hey guys I have a 97 SS camaro with the mods in my signature. My question is about a whirling or howl in the rear end aND a cyclical vibration.
I just noticed the other day that there was a small puddle under my rear end. I cleaned it off to pinpoint where it's coming from. It seems centered around the drain plug.
My rear end gets a whirling or howl mostly around 60mph but actually 50 since my speedo is off. Only when I'm not putting any load on it but it goes away as I slow down.
Also I get a cyclical vibration which I am told is from an imbalance drive shaft or bad pinion angle.
I do not know how long it has been leaking for so it could be low on fluid and this would cause a howling type of sound correct? Also I heard turning a drive shaft half way and putting it back helps with an imbalance. And last but not least if checking and or changing the pinion angle fix any of this will there be any long term affects to the gears. The rear end has about 1k on it and I'd hate to have parts replaced.
Thanks for any input guys and or gals
I just noticed the other day that there was a small puddle under my rear end. I cleaned it off to pinpoint where it's coming from. It seems centered around the drain plug.
My rear end gets a whirling or howl mostly around 60mph but actually 50 since my speedo is off. Only when I'm not putting any load on it but it goes away as I slow down.
Also I get a cyclical vibration which I am told is from an imbalance drive shaft or bad pinion angle.
I do not know how long it has been leaking for so it could be low on fluid and this would cause a howling type of sound correct? Also I heard turning a drive shaft half way and putting it back helps with an imbalance. And last but not least if checking and or changing the pinion angle fix any of this will there be any long term affects to the gears. The rear end has about 1k on it and I'd hate to have parts replaced.
Thanks for any input guys and or gals
08-29-2015, 07:41 PM
#2
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Re: Dana s60 rear end noise
When you installed it, did you check the pinion angle? Do you have an adjustable torque arm?
Why not check the level?
At what speed do you get the vibration? The stock DS are notorious for vibration at speeds above 60-70 MPH if you have installed higher numerical gears.
Why not check the level?
At what speed do you get the vibration? The stock DS are notorious for vibration at speeds above 60-70 MPH if you have installed higher numerical gears.
08-30-2015, 12:36 AM
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Re: Dana s60 rear end noise
When you installed it, did you check the pinion angle? Do you have an adjustable torque arm?
Why not check the level?
At what speed do you get the vibration? The stock DS are notorious for vibration at speeds above 60-70 MPH if you have installed higher numerical gears.
Why not check the level?
At what speed do you get the vibration? The stock DS are notorious for vibration at speeds above 60-70 MPH if you have installed higher numerical gears.
What is the best way to check the angle and to adjust it? It's been a while but I do have an angle finder. The driveshaft is not stock I have a 4l80e in the car do its a custom shaft...... again shouldn't it be balanced? The vibrations arent very noticeable in the lower speeds but cruising around say 50 and up its there. Also when I romp on it and get it going the vibrations intensify with the rpms. 3:73 gears btw. Checking the pinion angle should be my first start you think?
Thank u for any input u give me.
08-30-2015, 10:27 AM
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Re: Dana s60 rear end noise
Had no way of knowing the details of your drive line. Lack of a "signature" is always a problem. Logically a quality aftermarket DS will be properly balanced.
Harmonic vibration could easily be related to driveline geometry, as the u-joints are subjected to destructive forces that are generated when the angles at each joint are not close to identical. I would start by verifying the the engine/trans alignment is level. If the tail shaft is pointing up or downward at a severe angle, that has to be taken into account when setting the pinion angle.
Ideally, with the drivetrain under max torque load, you want the engin/trans axis parallel to the pinion shaft axis. That makes the u-joint angles equal. The Dana 60 has a higher pinion shaft centerline than the GM 10-bolt and 12-bolt reads, so that may be affecting the geometry. The torque reaction under load twists the nose of the pinion shaft upwards, and you a trying to set the static pinion angle so the upward movement of the pinion nose puts the system in the correct parallel alignment.
Harmonic vibration could easily be related to driveline geometry, as the u-joints are subjected to destructive forces that are generated when the angles at each joint are not close to identical. I would start by verifying the the engine/trans alignment is level. If the tail shaft is pointing up or downward at a severe angle, that has to be taken into account when setting the pinion angle.
Ideally, with the drivetrain under max torque load, you want the engin/trans axis parallel to the pinion shaft axis. That makes the u-joint angles equal. The Dana 60 has a higher pinion shaft centerline than the GM 10-bolt and 12-bolt reads, so that may be affecting the geometry. The torque reaction under load twists the nose of the pinion shaft upwards, and you a trying to set the static pinion angle so the upward movement of the pinion nose puts the system in the correct parallel alignment.
08-30-2015, 11:42 AM
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Re: Dana s60 rear end noise
Had no way of knowing the details of your drive line. Lack of a "signature" is always a problem. Logically a quality aftermarket DS will be properly balanced.
Harmonic vibration could easily be related to driveline geometry, as the u-joints are subjected to destructive forces that are generated when the angles at each joint are not close to identical. I would start by verifying the the engine/trans alignment is level. If the tail shaft is pointing up or downward at a severe angle, that has to be taken into account when setting the pinion angle.
Ideally, with the drivetrain under max torque load, you want the engin/trans axis parallel to the pinion shaft axis. That makes the u-joint angles equal. The Dana 60 has a higher pinion shaft centerline than the GM 10-bolt and 12-bolt reads, so that may be affecting the geometry. The torque reaction under load twists the nose of the pinion shaft upwards, and you a trying to set the static pinion angle so the upward movement of the pinion nose puts the system in the correct parallel alignment.
Harmonic vibration could easily be related to driveline geometry, as the u-joints are subjected to destructive forces that are generated when the angles at each joint are not close to identical. I would start by verifying the the engine/trans alignment is level. If the tail shaft is pointing up or downward at a severe angle, that has to be taken into account when setting the pinion angle.
Ideally, with the drivetrain under max torque load, you want the engin/trans axis parallel to the pinion shaft axis. That makes the u-joint angles equal. The Dana 60 has a higher pinion shaft centerline than the GM 10-bolt and 12-bolt reads, so that may be affecting the geometry. The torque reaction under load twists the nose of the pinion shaft upwards, and you a trying to set the static pinion angle so the upward movement of the pinion nose puts the system in the correct parallel alignment.
08-30-2015, 11:59 AM
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Re: Dana s60 rear end noise
I noticed you referenced the mods in your signature, but signature did not show up. That is often the result of posting from a phone app, some of which do not append the signature. You really lose a lot by not using the full site.
09-06-2015, 12:28 PM
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Re: Dana s60 rear end noise
Ok so I checked the pinion angle the rear pinion. Was at 0 and the driveshaft angle pointing toward the front end was about 1 or 2 degrees it was hard to tell bc I just crawled under the car lol. Now I would say the driveshaft could be out of balance but I don't believe I would get an out of balance shaft from the person who made it .
Maybe the angle of the transmission tail could be off from a too high or too low mount? With the 4l80e he had to make a custom tranny mount and customized the BMR tq arm to a body mount rather a tranny mount bc of the 4l80e. Also maybe a bad u joint? I also run MT drag radials at about 20 to 22 lbs
I've read that strange did say with poly bushings that there would be some noise and vibration but this seems a little excessive.
How much does a few degrees off angle would it affect a vehicle and vibration issues.
Let me know any opinions I have t kids so it may take time for me to respond back...
Maybe the angle of the transmission tail could be off from a too high or too low mount? With the 4l80e he had to make a custom tranny mount and customized the BMR tq arm to a body mount rather a tranny mount bc of the 4l80e. Also maybe a bad u joint? I also run MT drag radials at about 20 to 22 lbs
I've read that strange did say with poly bushings that there would be some noise and vibration but this seems a little excessive.
How much does a few degrees off angle would it affect a vehicle and vibration issues.
Let me know any opinions I have t kids so it may take time for me to respond back...
09-06-2015, 08:57 PM
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Re: Dana s60 rear end noise
Was the driveshaft pointing 1 - 2 degrees upward or downward as it went forward? You need accurate measurements, preferably with a magnetic digital angle finder/level.
The key to alignment is in my last paragraph...... With the driveline under max torque load you want the trans output shaft centerline parallel to the pinion shaft centerline. Static (no torque load) you want the pinion shaft centerline 1 - 2 degrees downward from the parallel line, so when when the pinion shaft/rear axle assembly rotates upward under load, the center lines at parallel.
If the engine/trans is level, and the pinion centerline is below the trans output shaft centerline, you want the difference between the pinion shaft and the driveshaft to be negative 1 - 2 degrees, resulting in a "\/" configuration, point pointing downward.
Yes, if the trans output shaft is not horizontal, pointing upwards or downwards, or if the S60 pinion centerline is above the trans output centerline, the geometry is different than the above.
I watched Steve Spohn (Spohn Performance) set mine with a $300 level gauge. He had just installed a custom heavy duty torque arm that we designed to clear the Gear Vendors O/D. He had the pinion shaft at a negative 1.8 degrees from the driveshaft, \/ pointing down. That was probably 10 years ago, and my 17 year old 12-bolt is still noise free.
The key to alignment is in my last paragraph...... With the driveline under max torque load you want the trans output shaft centerline parallel to the pinion shaft centerline. Static (no torque load) you want the pinion shaft centerline 1 - 2 degrees downward from the parallel line, so when when the pinion shaft/rear axle assembly rotates upward under load, the center lines at parallel.
If the engine/trans is level, and the pinion centerline is below the trans output shaft centerline, you want the difference between the pinion shaft and the driveshaft to be negative 1 - 2 degrees, resulting in a "\/" configuration, point pointing downward.
Yes, if the trans output shaft is not horizontal, pointing upwards or downwards, or if the S60 pinion centerline is above the trans output centerline, the geometry is different than the above.
I watched Steve Spohn (Spohn Performance) set mine with a $300 level gauge. He had just installed a custom heavy duty torque arm that we designed to clear the Gear Vendors O/D. He had the pinion shaft at a negative 1.8 degrees from the driveshaft, \/ pointing down. That was probably 10 years ago, and my 17 year old 12-bolt is still noise free.
09-07-2015, 08:02 PM
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Re: Dana s60 rear end noise
OK so I was finally able to get more into the car today. I think I have a few culprits. To be clear tho with the mods and everything I have with the car I do not expect it to run as quiet or vibration free as a brand new car, especially with poly bushing and body mounted tq arm etc but as stated these are some things that seem not quite right.
So again with the pinion angle and all I was able to work that out. Seems I made an error on it and it's now adjusted to a good angle.
Now with that said I did lose a lot of noise and vibrations. Car does feel a little better now.
To continue as I was under there I noticed a few things. My exhaust hanger for my y pipe is broke. I do get some bumps from it but I knew that it was the exhaust just didn't know the hanger was broken.
Also I think the cyclical vibration I am getting is an imbalance on one of my rear wheels. I cannot find a wheel weight on one of my rear tires but all the others have them. This could also be why I get the vibration through the car starting at about 50mph and getting worse the faster I go.
Now I just need to get these worked out and I will let u know.
Adjusting the pinion tho did get rid of a lot of vibration under load and also the rear end oil is coming from the gasket from the pumpkin cover.
Seems like I have quite a bit of small issues which I am much happier with than one big one. I'll keep u updated on how it works out.
So again with the pinion angle and all I was able to work that out. Seems I made an error on it and it's now adjusted to a good angle.
Now with that said I did lose a lot of noise and vibrations. Car does feel a little better now.
To continue as I was under there I noticed a few things. My exhaust hanger for my y pipe is broke. I do get some bumps from it but I knew that it was the exhaust just didn't know the hanger was broken.
Also I think the cyclical vibration I am getting is an imbalance on one of my rear wheels. I cannot find a wheel weight on one of my rear tires but all the others have them. This could also be why I get the vibration through the car starting at about 50mph and getting worse the faster I go.
Now I just need to get these worked out and I will let u know.
Adjusting the pinion tho did get rid of a lot of vibration under load and also the rear end oil is coming from the gasket from the pumpkin cover.
Seems like I have quite a bit of small issues which I am much happier with than one big one. I'll keep u updated on how it works out.
09-07-2015, 08:56 PM
#12
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Re: Dana s60 rear end noise
Check the rear tire pressures (cold) and make sure they are identical. Make sure both the rear tires have the same diameter. The can be accomplished by measuring the circumference with a string at the center of the tread. Not likely the cause of the cyclic noise, but worth checking.
I bought a digital tire pressure gauge calibrated to 1/10th of a PSI. While it was mainly for my slicks, I use it on all my vehicles, including the SUV my employer provides.
I bought a digital tire pressure gauge calibrated to 1/10th of a PSI. While it was mainly for my slicks, I use it on all my vehicles, including the SUV my employer provides.
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