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O ring found on the end of stock axels.

  • Thread starter Thread starter Blueinfan
  • Start date Start date Oct 13, 2021
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Blueinfan

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#1
  • Oct 13, 2021
  • #1
Hi Mustang community,

Need some help. I removed the axel from my 1991 Ford Mustang Convertible and noticed that the axels had an O ring where the C-Clip goes. Does anyone know what purpose do they have there, where can I get them, and official name?
 

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manicmechanic007

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#2
  • Oct 13, 2021
  • #2
Find another one
It is supposed to be there to cushion the axle noise
 
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Blueinfan

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#3
  • Oct 13, 2021
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manicmechanic007 said:
Find another one
It is supposed to be there to cushion the axle noise
Click to expand...
Can I use any O rings or have to use one made for the axel?
 

manicmechanic007

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#4
  • Oct 13, 2021
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You may not find another that works easy without Ford Parts counter
I do not remember the size but a standard o ring kit does not have the right one I think
Call a place like Six States
 

manicmechanic007

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#5
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It is a regular o ring
I think any one you find that lets you install the c clip would be okay
Red green black blue yes sir its just there for a little cushion
 
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Blueinfan

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#6
  • Oct 13, 2021
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manicmechanic007 said:
It is a regular o ring
I think any one you find that lets you install the c clip would be okay
Red green black blue yes sir its just there for a little cushion
Click to expand...
Thank you!
 
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Blueinfan

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#7
  • Oct 13, 2021
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Blueinfan said:
Thank you!
Click to expand...
I'm going to buy one and put it back the way it was from the factory.
 
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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Oct 13, 2021
#8
  • Oct 13, 2021
  • #8
Nitrile ( Buna-N) and viton are a common o-ring material that will tolerate oils well. Viton will take a bit more heat, but I don’t think in this application it matters

O-rings are standard sizes. Should be easy to track down one of similar size.

Let me see if I have one of those kicking around to measure and get the standard size


Edit: it appears to be a -018 size O-ring. My o ring is a bit beat up as well, so it’s possible it’s stretched and really a -017. I can grab a few at work tomorrow to try out.
 
Last edited: Oct 13, 2021
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7991LXnSHO

wanna catch the space herp
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#9
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Why hav
Mustang5L5 said:
Nitrile ( Buna-N) and viton are a common o-ring material that will tolerate oils well. Viton will take a bit more heat, but I don’t think in this application it matters

O-rings are standard sizes. Should be easy to track down one of similar size.

Let me see if I have one of those kicking around to measure and get the standard size


Edit: it appears to be a -018 size O-ring. My o ring is a bit beat up as well, so it’s possible it’s stretched and really a -017. I can grab a few at work tomorrow to try out.
Click to expand...
Why have I not heard of or read about this before?
There were no O rings on the axle ends in my 87 Cougar. (I think the standard V-6 had a 7.5” diff, but the same axle set up.) The rear would clunk when shoved side to side when parked. The Stealership said that was normal, and I found nothing that looked worn and nothing else wrong except end play. This probably would have helped for a few miles.
I would want as tough an o ring as I could get, for both gear oil and sideways forces.
 

Mustang5L5

That is…until I whipped out my Bissell
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#10
  • Oct 13, 2021
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I always thought the purpose of the O-ring was simply to hold the C-clips in place during assembly. The c-clip just slides over the o-ring and the tension holds it in place

With the C-clip in place, and the axles pulled outwards with the center pin in place, there really isn't a whole lot of movement in the c-clip. I don't see how a little rubber O-ring is going to help with NVH but it's not something I really put much thought into.

On the used axles I checked, only 1 had the o-ring intact, and it was pretty crushed. In fact, it has two flats that aligned perfectly with where the C-clip fit over it. Supports the "assembly holding device" theory. I wouldn't lose any sleep over not putting it back on.
 

manicmechanic007

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#11
  • Oct 14, 2021
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Yours will be noisy then 5L5
 

OldManRiver

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#12
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The O-rings have absolutely nothing to do with deadening noise,they were installed as an assembly aid.
 
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91TwighlightGT

20+ Year Stangneter
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#13
  • Oct 14, 2021
  • #13
I think they are probably as good at reducing noise as the hood insulator is at being a fire blanket.
 
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Mustang5L5

That is…until I whipped out my Bissell
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Oct 14, 2021
#14
  • Oct 14, 2021
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I didn’t have any -018 o-rings but a -017 fit fine
 
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manicmechanic007

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#15
  • Oct 14, 2021
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OldManRiver said:
The O-rings have absolutely nothing to do with deadening noise,they were installed as an assembly aid.
Click to expand...
You are mistaken
 

General karthief

wonder how much it would cost to ship you a pair
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#16
  • Oct 14, 2021
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Does it matter??
Prolly not.
Never noticed an O ring on any axle I've removed.
I'm with the assembly aid theory
But until proof surfaces, does it matter?
I think not.
 

manicmechanic007

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#17
  • Oct 15, 2021
  • #17
I stand corrected c clip retention it is
Not sure when they started using them
1991 or so
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,265
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Massachusetts
Oct 15, 2021
#18
  • Oct 15, 2021
  • #18
I don’t think it’s a subject worth debating.

If you want to stick them back on, -017 or -018 o-ring is what you want. I used the -017 although I think -018 is the correct size. I’m just unable to confirm as I don’t have that size in my o-ring bin because one of my minions failed to reorder.
 

7991LXnSHO

wanna catch the space herp
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#19
  • Oct 15, 2021
  • #19
Mustang5L5 said:
I don’t think it’s a subject worth debating.

If you want to stick them back on, -017 or -018 o-ring is what you want. I used the -017 although I think -018 is the correct size. I’m just unable to confirm as I don’t have that size in my o-ring bin because one of my minions failed to reorder.
Click to expand...
Is this the employee?
 
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General karthief

wonder how much it would cost to ship you a pair
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#20
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(Feverishly looking for that Trump 'you're fired' gif (or meme or whatever they are called)
 
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