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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

1987 8.8 Rear End

  • Thread starter Thread starter dozergreen
  • Start date Start date Mar 6, 2014
D

dozergreen

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Feb 19, 2014
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#1
  • Mar 6, 2014
  • #1
is my 8.8 rear end a 28 spline or did they come out with other splines
 

CarMichael Angelo

my rearend will smell so minty fresh,
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#2
  • Mar 6, 2014
  • #2
it's 28 spline. 31 splines are an aftermarket upgrade.
 
D

dozergreen

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#3
  • Mar 6, 2014
  • #3
madmike1157 said:
it's 28 spline. 31 splines are an aftermarket upgrade.
Click to expand...
ok with that being cleared up I have the tag off it the top line reads 431D the second line reads 3SL55 8.8 8F17 what does the SL stand for I know its 3:55 ratio but is it a locker or limited slip
 

CarMichael Angelo

my rearend will smell so minty fresh,
15 Year Member
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Mar 6, 2014
#4
  • Mar 6, 2014
  • #4
dozergreen said:
ok with that being cleared up I have the tag off it the top line reads 431D the second line reads 3SL55 8.8 8F17 what does the SL stand for I know its 3:55 ratio but is it a locker or limited slip
Click to expand...
Can't tell you what the numbers and letters mean,...ford only put traction loc differentials in as opposed to open diffs. If turning one wheel the other goes in the opposite direction, it's open, and will only spin one tire. If both tires spin in the same direction, AND.....(get a friend to help, or stick a crowbar through the studs that will get jammed between the ground so that tire will not spin) if the tire you're trying to turn will not turn,...then you have a clutch based traction loc differential.

Ford only put a "locker" in a 9",.....and you'd know you had it as soon as you drove it.
 

88LX5.Oh

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Dec 30, 2011
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#5
  • Mar 6, 2014
  • #5
I've never seen an SL one. I usually see stuff like 3L08 or 3L55 where the single L means limited slip. Yours shouldn't be 3.55s because they didn't offer them for the '87. Pretty sure all that was offered were 2.73's, 3.08's, and 3.27's IIRC.
 

84Ttop

They make new pistons every day, so why worry?
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#6
  • Mar 6, 2014
  • #6
Who knows what has been changed since 1987. We are all speculating at this point. Don't assume the tag is 100% accurate or even that you have 28 spline axles. Need to do some checking...
 
D

dozergreen

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Mar 7, 2014
#7
  • Mar 7, 2014
  • #7
84Ttop said:
Who knows what has been changed since 1987. We are all speculating at this point. Don't assume the tag is 100% accurate or even that you have 28 spline axles. Need to do some checking...
Click to expand...
ill just pull the cover and see what ive got thanks for all the info
 
D

dozergreen

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Mar 9, 2014
#8
  • Mar 9, 2014
  • #8
ok mystery solved this rear end is a 1988 8.8 with track lock and 3:55 gears out of a thunder chicken
 
D

dozergreen

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#9
  • Mar 9, 2014
  • #9
now with that out of the way how do I lock it up will a mini spool work
 

mikestang63

SN Certified Technician
Aug 27, 2012
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Mar 9, 2014
#10
  • Mar 9, 2014
  • #10
dozergreen said:
now with that out of the way how do I lock it up will a mini spool work
Click to expand...

You can do that or guys weld the spider gears. Why do you want a locker? It is terrible on the street. I used to have an old Richmond and it would click click click on turns.
 

CarMichael Angelo

my rearend will smell so minty fresh,
15 Year Member
Nov 29, 1999
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Mar 9, 2014
#11
  • Mar 9, 2014
  • #11
A locked rear end is your guaranteed appoint with the curb at the very next instance of rain. It is not a good idea for safety's sake, not to mention the added stress that will be put on the poor old 28 spline C-clip axles as a result.

If you are wanting to improve the performance of the T-loc,..rebuild it.
If you want something better, Eaton, Auburn, and Detroit all make replacement diffs that are far superior to the old T-loc, They will all cost you somewhere between 400-600.00.
 

84Ttop

They make new pistons every day, so why worry?
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Mar 10, 2014
#12
  • Mar 10, 2014
  • #12
I second the notion of just putting new clutches in the trac lok and rock and roll!!!
 
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