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I was determine to get rid of my car’s rear end whine ( changed gears twice, checked set up twice, changed brand of gear oil, dynamat trunk and rear seat areas, etc ). Damn it nothing got rid of or even reduced the gear whine.

I almost threw in the towel and then decided to try a heavier weight gear oil. Swapped out the 80/140 gear oil with 75/250 gear oil and it made a very noticeable improvement ! Its not a total solution but its a HUGE improvement. I only hear occasional gear whine now, much more enjoyable to drive. ( btw, not recommended for use when below 40 degrees ).
 

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What fluid did you go with? I been meaning to drain mine and try Amsoil. I had RP in both my 373 diff cars and they both whine like crazy.
I have RP in the trans too and absolutely despise it!
 

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What fluid did you go with? I been meaning to drain mine and try Amsoil. I had RP in both my 373 diff cars and they both whine like crazy.
I have RP in the trans too and absolutely despise it!

I am with you on the RP in the rear end, allot of noise! Use the Mobil 1 syn ATF in the transmision. It is the way to go in the transmision.
 

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I was determine to get rid of my car’s rear end whine ( changed gears twice, checked set up twice, changed brand of gear oil, dynamat trunk and rear seat areas, etc ). Damn it nothing got rid of or even reduced the gear whine.

I almost threw in the towel and then decided to try a heavier weight gear oil. Swapped out the 80/140 gear oil with 75/250 gear oil and it made a very noticeable improvement ! Its not a total solution but its a HUGE improvement. I only hear occasional gear whine now, much more enjoyable to drive. ( btw, not recommended for use when below 40 degrees ).
There has been a lot of threads on this issue. I too have had whine issues. What brand of gears did you go with for your swaps? What kind of break did you use? Do you do a lot of hard launches? Wonder if there is something wrong with the housing?
 

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I am with you on the RP in the rear end, allot of noise! Use the Mobil 1 syn ATF in the transmision. It is the way to go in the transmision.
I was gonna do AMSoil in everything, but I may do the Mobil1 in my trans in hopes for easier cold shifting. I ran M1 in my severely overpowered 170k mile and abused T5 in my SN and I swear that was the reason that trans stayed together. It was an anomoly and just took everything I threw at it. . . Man I really miss a toploader. lol
 

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You might want to check with a experienced rear end shop. The guy I know in the business told me never exceed 140 weight oil. anything heavier was made for slow turning gears and this is because the heavier the oil the more heat it generates. and this can cause Bearing failure. and on the highway these rears get hot. I have seen several deformed gears because of heat. If it was a good fix increasing the oil weight everyone would do it!
 

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Discussion Starter #8
Gear whine is inherent in the 8.8
The message I was attempting to share with others is going to 75/250 gear oil will Noticeably decrease rear end gear whine. The issue is practically nobody knows 75/250 gear oil is available.
And no Joe the multi viscosity will preclude overheating.
 

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I have been setting up gears since, well lets see... 1976. I had a Mustang Restoration shop in the Denver aarea. Over the years I have set up a few, a bunch, of gear sets. Nearly two years ago I put a set of 373s in my Shelby, no whine to be of concerne. Where are you folks having this done? Are you sure they know what they are doing? If set correctly with pattern , preload and backspace there should be no issue with gear and/or bearing noise. 'Heavier oil' will run hotter.
I'm not an expert but I have set up dozens upon dozens of rear gear sets without annoying 'noise', find someone that has experience and KNOWS how to do it correctly. Sometimes you will get bad gears, but not often. It takes time and sometimes two or three times to get it right, preload and pattern often talkes a couple iterations to get it right with the proper backlash... have you watched it done, were they using a dial gauge, checking run pattern? I have a nodular (N case) nine inch with 411s and a Detroit locker narrowed to 48 inches going into my 426 Plymouth and I know there will not be an objectional 'whine'. It took three crush sleeves to get it right, that means taking it apart and back together three times to get the right shims in it. Not everyone will do that, too much trouble, they will settle with close enough.... Get someone that will get it right!
Sorry for the little rant, but it is somewhat aggregating to hear about excessive gear whine when it CAN be done correctly!

I'll go back to my napping now, thats what retired people do.
 

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I have been setting up gears since, well lets see... 1976. I had a Mustang Restoration shop in the Denver aarea. Over the years I have set up a few, a bunch, of gear sets. Nearly two years ago I put a set of 373s in my Shelby, no whine to be of concerne. Where are you folks having this done? Are you sure they know what they are doing? If set correctly with pattern , preload and backspace there should be no issue with gear and/or bearing noise. 'Heavier oil' will run hotter.
I'm not an expert but I have set up dozens upon dozens of rear gear sets without annoying 'noise', find someone that has experience and KNOWS how to do it correctly. Sometimes you will get bad gears, but not often. It takes time and sometimes two or three times to get it right, preload and pattern often talkes a couple iterations to get it right with the proper backlash... have you watched it done, were they using a dial gauge, checking run pattern? I have a nodular (N case) nine inch with 411s and a Detroit locker narrowed to 48 inches going into my 426 Plymouth and I know there will not be an objectional 'whine'. It took three crush sleeves to get it right, that means taking it apart and back together three times to get the right shims in it. Not everyone will do that, too much trouble, they will settle with close enough.... Get someone that will get it right!
Sorry for the little rant, but it is somewhat aggregating to hear about excessive gear whine when it CAN be done correctly!

I'll go back to my napping now, thats what retired people do.
I have set up a few 9" third members myself back in the day. I never used any sort of dial indicator. I always used white lead to see the pattern I wanted and shimmed accordingly. I always set them up like Example "A" and nevah had any gear whine on the drive side or coast side. Yes it does take some time to get it right.

200640
 

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The white lead or yellow grease is to check the run pattern. The dial gauge is used to set the backlash, which needs to be between .007 to .010. It is adjusted with the locking load ring nuts of the ring gear on a nine inch. The 8.8 does not have these, it is done by the shims on either side on the ring gear to move it to or from the pinion. The backlash is important to get correct. A dial gauge/indicated is the ONLY way to set this correctly without 'guessing'. Most 'factory' set gears will be between .07 and .017, they do not always use the dial gauge like a lot of other builders, setting them by gauge is a better more accurate method.

Now back to my nap.
 

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I had 411 gears installed in November and my gears are silent. and I agree with Cause Backlash is were the whine most likely comes from. And to you other statement we all know 250 exists its just not meant for this application! We are just trying to save you problems.
 

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Seems the tighter tolerance for backlash is less problematic. Mine is at .010" and I have no whine. However, once it starts I don't think you'll get rid of it unless it's a fresh install. I have heard of rear ends being set up that had no problems until it had hard launch on drag radials/slicks. I have to wonder how well a crush sleeve works in that sort of application. If I were to change to 4.10s, I will resort to a crush sleeve eliminator. I intended to install one when I installed my True Trak, but I whimped out. If it ain't broke.....
 

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Seems the tighter tolerance for backlash is less problematic. Mine is at .010" and I have no whine. However, once it starts I don't think you'll get rid of it unless it's a fresh install. I have heard of rear ends being set up that had no problems until it had hard launch on drag radials/slicks. I have to wonder how well a crush sleeve works in that sort of application. If I were to change to 4.10s, I will resort to a crush sleeve eliminator. I intended to install one when I installed my True Trak, but I whimped out. If it ain't broke.....
John you are absolutely correct, I'm not too concerned regarding setting up with the pinion crush sleeve, I have always used them and trust me when I say I have done my full share of hard launches. They have worked for me in 9 inchers since I learned how to it in around '76. (so about 44 years ago) I believe in stay with what you KNOW.
I too, like you have to believe that those with the 'whine' have gears set up too lose and then hammering on those exasperates the issue.
Just my somewhat experienced opinion and not that of the management...
 
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