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8.8 Gear Swap "need Help"

  • Thread starter Thread starter Cobraj93
  • Start date Start date May 3, 2016
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Cobraj93

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May 3, 2016
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May 3, 2016
#1
  • May 3, 2016
  • #1
Hi All! I am performing a gear swap in my 93 GT. I am replacing a 3.73 with a 4.10. (Both Ford Racing gearsets). Also replacing diff with Detroit Truetrac and 31 spline Moser axles. All bearings, races, and seals replaced. My question is with the gear wear pattern I am getting. It seems to be wiping the marking compound off of the complete tooth rather than a small section like I think it should have. I'm not sure if it's my pinion depth is set wrong and causing it. I have 22 in/lbs of drag on pinion. I used the same shim that I removed from the old pinion since they were both Ford Racing. It was a .025" shim. I have between .008" and .010" of backlash on the ring gear. Anybody have any ideas? I have attached some pictures.



 

Davedacarpainter

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May 6, 2016
#2
  • May 6, 2016
  • #2
That's a good question, I'm getting ready to put my rear together with all new pieces too.

That is a wide pattern, I would think pinion depth would be the problem.

Let me get our resident genius to chime in, if he doesn't know, he'll know where to get the answer.

@jrichker , help.
 

jrichker

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#3
  • May 6, 2016
  • #3
Google is your friend...

Pick the picture that best matches your pattern and select to open the page associated with it...
https://www.google.com/search?q=rin...Oil7nM:;yjASb_unn7K9SM:&imgrc=UCLoTvjYOil7nM:
 
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Cobraj93

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May 3, 2016
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May 7, 2016
#4
  • May 7, 2016
  • #4
After much research I found out there are 2 machining processes used in machining ring and pinion gears. The 2 processes are "face milled" and "face hobbed". All new Ford 8.8-inch original equipment and Ford Racing gears are face hobbed. This is where I was messing up. Face hobbed gear sets have a different set up procedure when making adjustments. All the searches I found on Google showed only the adjustments for face milled gears. Check out this link. It is extremely informative.
http://diyford.com/ford-axle-ring-pinion-assembly-guide/
 
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Davedacarpainter

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Nov 28, 2015
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May 8, 2016
#5
  • May 8, 2016
  • #5
Cobraj93 said:
After much research I found out there are 2 machining processes used in machining ring and pinion gears. The 2 processes are "face milled" and "face hobbed". All new Ford 8.8-inch original equipment and Ford Racing gears are face hobbed. This is where I was messing up. Face hobbed gear sets have a different set up procedure when making adjustments. All the searches I found on Google showed only the adjustments for face milled gears. Check out this link. It is extremely informative.
http://diyford.com/ford-axle-ring-pinion-assembly-guide/
Click to expand...
I've learned a new thing! Thanks brother.
 
C

Cobraj93

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May 3, 2016
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May 8, 2016
#6
  • May 8, 2016
  • #6
No problem. Hopefully this will help with your rebuild!!
 

Davedacarpainter

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May 9, 2016
#7
  • May 9, 2016
  • #7
Cobraj93 said:
No problem. Hopefully this will help with your rebuild!!
Click to expand...
It will, thanks
 
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