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Rear End De-code ?

  • Thread starter Thread starter Bad67MF
  • Start date Start date Dec 4, 2004

Bad67MF

Member
Sep 29, 2004
60
0
6
Sparks Nevada
Dec 4, 2004
#1
  • Dec 4, 2004
  • #1
I picked up a rear end and was told that it came from an 86' 5.0. I know it is 4-lug and possibley a 7.5 but not sure. Could anybody help with de-coding the tag # ?
201A
2SL73A887L19
Thanks!
 

jb89coupe

New Member
Sep 3, 2004
416
0
0
CT
Dec 4, 2004
#2
  • Dec 4, 2004
  • #2
Bad67MF said:
I picked up a rear end and was told that it came from an 86' 5.0. I know it is 4-lug and possibley a 7.5 but not sure. Could anybody help with de-coding the tag # ?
201A
2SL73A887L19
Thanks!
Click to expand...

273 8.8"
 

Bad67MF

Member
Sep 29, 2004
60
0
6
Sparks Nevada
Dec 4, 2004
#3
  • Dec 4, 2004
  • #3
jb89coupe said:
273 8.8"
Click to expand...
Are you sure 8.8? The bolt pattern has 10 bolts, 2 of them are in the center up and down like the pic's I se of 7.5's. And not in the center from side to side like the pic's of the 8.8. Thanks for your help. I am going to sell this and just don't want to misrepresent it.
 

bryanrevans

New Member
Sep 10, 2004
296
0
0
Chicopee,Mass
Dec 4, 2004
#4
  • Dec 4, 2004
  • #4
86 was first year of 8.8 wich is 10 bolt pattern.Maybe thats not 86???What part of tag lets you know its 2.73
 

jb89coupe

New Member
Sep 3, 2004
416
0
0
CT
Dec 4, 2004
#5
  • Dec 4, 2004
  • #5
bryanrevans said:
86 was first year of 8.8 wich is 10 bolt pattern.Maybe thats not 86???What part of tag lets you know its 2.73
Click to expand...
2SL73A887L19 = 2xx73x88xxxx = 2.73, 8.8"
This method is from some website I stumbled on a while back, so I guess there's a chance it's wrong, but it's been right every time I've used it. I'll dig through my favorites folder and see if I can find out what the other stuff means too.
 

Cobra tt

New Member
Dec 4, 2004
21
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0
Dec 4, 2004
#6
  • Dec 4, 2004
  • #6
I have a narrow crown victoria rear end with 3:55 gears, Daytona rims to boot!
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Dec 4, 2004
#7
  • Dec 4, 2004
  • #7
The gear ratio is easy - just rotate the pinion flange and count the ratio of pinion turns to one turn of the axle. So many of these have been modded that I wouldn't trust the part number to indicate the gear ratio that's in the housing anyway. While you're spinning things - rotate one axle and watch the other. If the other axle rotates in the same direction, you've got a working traclok. If the other axle rotates in the opposite direction then you've either got a non-working traclok, or you've got an open diff.
 
J

JB66

New Member
Aug 21, 2004
565
1
0
New York
Dec 4, 2004
#8
  • Dec 4, 2004
  • #8
axle decoding courtesy of coldfusion

Maybe this will help.
 

Attachments

  • axletag.webp
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Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Dec 4, 2004
#9
  • Dec 4, 2004
  • #9
That's great JB66 - clear and easy to understand. That should help with the 8.8 vs 7.5 part. Only helps with the gear ratio if you know the entire history of the rear end and that it's never been re-geared.
 
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