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31 Spline Conversion Question

  • Thread starter Thread starter foureyefox347
  • Start date Start date Jan 18, 2014

foureyefox347

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Jan 18, 2014
#1
  • Jan 18, 2014
  • #1
So I put a 28 spline set up together richmond 3.73s and carbon clutch packs now my question is can I just change my 2 spider gears that have the splines and put 31 spline axle in or is the carrier a different size And im guessing the end bearing and seal is different
 

Noobz347

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#2
  • Jan 18, 2014
  • #2
http://www.stangnet.com/mustang-forums/threads/28-to-31-spline.874356/#post-8789927
 

25thmustang

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Sep 5, 2003
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Jan 18, 2014
#3
  • Jan 18, 2014
  • #3
You need a 31 spline carrier and axles. I used a truck 31 spline carrier and FMS axles. Around $250 and I had 31s over my 28s...
 

foureyefox347

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Jan 18, 2014
#4
  • Jan 18, 2014
  • #4
but ive been looking in to are part catalog thou ford and it looks like the carriers for a 98 explorer and a 90 mustang are the same part number so i don't see y i couldn't just swap the spider gears and s clip with out putting new carrier in then i wouldn't have to take it back apart cuz all i would have to do is take the pin out take the s clip out pull the c clips pull axles turn the top spiders out and pull the 28 spline gears and put in the clutch packs on the 31 spline gears and put it back together the other question i have is i took some out of a 8.8 irs im worrying if they would work and the other question is do i have to get new axle bearings and seals cuz there thicker and im getting the moser 4 lug 31 spline axles so idk
 

foureyefox347

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Jan 18, 2014
#5
  • Jan 18, 2014
  • #5
nvm about the same part number thing they have a different part number i was looking at the catalog wrong
 
M

mind84

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Nov 26, 2013
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Jan 19, 2014
#6
  • Jan 19, 2014
  • #6
I am in the middle of gathering parts for my differential rebuild and mod. I don't know about just being able to swap out the spider gears but you will need to get new housing ends welded in for larger bearings. Strangeengineering seems to make good ones for $70. Looked into going to 31spline but decided on just going to stronger components as I plan on a mild street build. I found this article helpful:


http://www.carcraft.com/techarticles/116_ford_8_8_rear_end/
 

madspeed

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Jan 19, 2014
#7
  • Jan 19, 2014
  • #7
foureyefox347 said:
but ive been looking in to are part catalog thou ford and it looks like the carriers for a 98 explorer and a 90 mustang are the same part number so i don't see y i couldn't just swap the spider gears and s clip with out putting new carrier in then i wouldn't have to take it back apart cuz all i would have to do is take the pin out take the s clip out pull the c clips pull axles turn the top spiders out and pull the 28 spline gears and put in the clutch packs on the 31 spline gears and put it back together the other question i have is i took some out of a 8.8 irs im worrying if they would work and the other question is do i have to get new axle bearings and seals cuz there thicker and im getting the moser 4 lug 31 spline axles so idk
Click to expand...


Punkt u a shun would be great
 

RangerJoe

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#8
  • Jan 19, 2014
  • #8
No, it won't work. I tried it a few years ago. If I remember correctly, it had something to do with the retaining pin being different. The bearings and seals are the same though.

Joe
 
M

mind84

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Nov 26, 2013
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Jan 19, 2014
#9
  • Jan 19, 2014
  • #9
RangerJoe said:
No, it won't work. I tried it a few years ago. If I remember correctly, it had something to do with the retaining pin being different. The bearings and seals are the same though.

Joe
Click to expand...
So am I getting something wrong here guys. From what I saw the the 31 spline axle is much larger in diameter, hence the higher spline count. Larger axles would require a larger bearing and the space for it i.e. housing ends. Unless they make a bearing with the same outer diameter and larger inner race with smaller bearings, but that would defeat the purpose. Can some one explain this.
 

RangerJoe

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Jan 20, 2014
#10
  • Jan 20, 2014
  • #10
mind84 said:
So am I getting something wrong here guys. From what I saw the the 31 spline axle is much larger in diameter, hence the higher spline count. Larger axles would require a larger bearing and the space for it i.e. housing ends. Unless they make a bearing with the same outer diameter and larger inner race with smaller bearings, but that would defeat the purpose. Can some one explain this.
Click to expand...

The bearing are the same. Remember, the bearings press over the carrier where the axles enter. Any axle size difference is probably made up with the thickness of the carrier material. I say all this because I bought standard replacement bearings for my 31 spline differential. They worked out fine.

1993 Mustang replacement bearing for 28 spline carrier.

http://www.autozone.com/autozone/pa...6o3ap?itemIdentifier=788570_677165_6534_29009

2000 Ford Explorer with 31 spline carrier.

http://www.autozone.com/autozone/pa...je79jZ6o3ap?itemIdentifier=788570_483688_6534_

Same part number.

Joe
 
M

mind84

Member
Nov 26, 2013
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Jan 20, 2014
#11
  • Jan 20, 2014
  • #11
I thought he was talking about axle bearings not carrier bearings. Nevermind then, my world makes sense again.
 

foureyefox347

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Waukesha, Wisconsin
Jan 21, 2014
#12
  • Jan 21, 2014
  • #12
i am asking about the axle bearings the carrier bearings should be the same but i did some more research and i have to buy a 31 spline carrier anyways but i guess my only question left is will the axles fit in my tubes with 28 spline axle bearing and seals and if no does anyone know the part numbers of what i need to use
 

RangerJoe

I leave the horn on while driving
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#13
  • Jan 21, 2014
  • #13
Lol. My bad. My 31 spline axles came with new axle bearings, most do. I would call the manufacturer of the axles and ask.

Joe
 
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