Ford 9" trac loc differential numbers
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
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From: Simi Valley, CA
Originally Posted by oem78
Can you please tell me what all these numbers and letters mean. Is this a 28 or 31 spline.Thanks
WDM CN 9EB
350 9 361 A
WDM CN 9EB
350 9 361 A
1973/79 Ford Light Truck Parts Catalog ~ Section 40 ~ Parts List #88
WDM-CN = Ford 9 inch / 31 spline / 3.50-1 / non Limited slip
2-D6TZ-4234-A .. Axle Shaft-31 spline / Use w/ 1/2" brake backing plate bolts.
2-D8TZ-4234-D .. Axle Shaft-31 spline / Use w/ 3/8" brake backing plate bolts
Note: Ford changed the brake backing plate bolt sizes in 1979, why there are two different axles for the same application.
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Tuned
Joined: Oct 2003
Posts: 390
Likes: 2
I was just explaining my axle situation( wanting limited slip or trac-lock or posi traction) to a couple of guys at work, they said all ford 4x4 had limited slip, I said they were wrong, so we went out to the parking lot with packed snow, I started her up and put it in second gear let the clutch out and both rear tires were spinning, then put it in reverse and only the drivers side spun, put it in second again and hit the gas and both tires spun agian , put it in reverse and only the pass. tire spun. What kind of a set up do I have ? tag numbers are listed:
WDW CN 9EB
3 50 9 361 A
Maybe there is a L between the 3 and the 5 on the gear ratio, I will look again tonight, there is definitely a space between the 3 and the 50. It looks like this 3 50. Is there normally a space between these numbers on the tag?
WDW CN 9EB
3 50 9 361 A
Maybe there is a L between the 3 and the 5 on the gear ratio, I will look again tonight, there is definitely a space between the 3 and the 50. It looks like this 3 50. Is there normally a space between these numbers on the tag?
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
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From: Simi Valley, CA
Originally Posted by Mil1ion
Bill, Where EXACTLY in parts list 88 does is typed 31 spline ?
I added the spline count along with the axle part numbers to assist the OP.
> > Go to parts list #88, find the axle part numbers that refer to WDM-CN.
Then go to Ford basic part number 4234 = Section 41, pages 6 & 7.
Read down till you find the correct part numbers.
Not only is the spline count given, but other pertinent info like measurements.
Last edited by NumberDummy; Jan 3, 2008 at 03:30 AM.
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 783
From: Simi Valley, CA
Originally Posted by oem78
I was just explaining my axle situation( wanting limited slip or trac-lock or posi traction) to a couple of guys at work, they said all ford 4x4 had limited slip, I said they were wrong, so we went out to the parking lot with packed snow, I started her up and put it in second gear let the clutch out and both rear tires were spinning, then put it in reverse and only the drivers side spun, put it in second again and hit the gas and both tires spun agian , put it in reverse and only the pass. tire spun. What kind of a set up do I have ? tag numbers are listed:
WDM CN
WDM CN
Verbatum from the Ford parts catalog:
Ford WDM (Non Locking) Service Parts List 88.
If your truck had Limited Slip originally, the axle code suffix (CN) would have been different.
Then it would fall under: Ford WDM (Locking) Service Part List 193.
Limited Slip is an option. So 2 or 4WD could be had with LS...IF the customer ordered it.
Last edited by NumberDummy; Jan 3, 2008 at 03:33 AM.
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Tuned
Joined: Oct 2003
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Detroit locker
I am looking a NOS Detroit locker. The old box looks like a ford box with the number M-4201-D31. I would like to know if this will fit my 1979 F150 9" rear axle with 31 splines? Did Ford use Detroit locker in there 9" rear ends on the F150's if so this is likely a oem part ??
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Tuned
Joined: Oct 2003
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1979 trac loc differential 3rd member Identify numbers
I finally got to the yard and pulled a 3rd member out of a 1979 F150 rear axle 9" with the axle code 3L50. Just for information can anybody tell me what these numbers mean that are on the 3rd member or differential. What looks like a tag with two screws reads 9A10. Stamp in the metal below this tag like thing is W-4205.
Last edited by oem78; Jan 21, 2008 at 10:25 PM. Reason: left information out
Elder User
Joined: Nov 2003
Posts: 778
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From: southeast Idaho
Million, could they have been special ordered from the factory with locker installed or would it have been a dealer installed option? I ask simply because I know of vehicles coming with what was called a no-spin rear end which I believe is another name for detroit locker type rearends. I bought one from a guy about 15 yrs ago that he said was no-spin and found that was actually a detroit locker, he just wanted to change his ratio for better mileage and I just figured I would use it someday and am running it right now to see how well it works and except for the squirllies when it resets it works quite well..
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Tuned
Joined: Oct 2003
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Ford 9" trac loc differential numbers
I finally got to the yard and pulled a used trac loc differential. It cam out of a 1979 F150 4x4 with a 9" Ford rear axle, with a tag that read 3L50. I took the center or 3rd member out, was told it was in good working order when the engine failed in the truck. I would like to know what these numbers are on the center differential. It looks like a tag is on the part, but it is really molded into the metal to look like a tag with two scews, it reads 9A10.
Then stamped below into the metal it reads W- 4205. Any help with these numbers, thanks.
Then stamped below into the metal it reads W- 4205. Any help with these numbers, thanks.
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