Axle code double check - Numberdummy?
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Cross-Country
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From: Texas
Axle code double check - Numberdummy?
1979 F150, no tag on axle, door sticker has axle code 13.
Internet has many references saying 2.75 gear, question: Can code confirm 31 spline axles with large bearing?
Internet has many references saying 2.75 gear, question: Can code confirm 31 spline axles with large bearing?
Ford Parts Specialist
Joined: Nov 2006
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From: Simi Valley, CA
Without the tag, I cannot confirm whether the axle shafts have 28 or 31 splines. It's probably 31, based on the 3,750 lbs. axle capacity
If the tag number is known, it's listed with a specific part number axle shafts in one of the two 9" parts lists.
Then you find the part number in the rear axle shaft application chart to get the specs. This has been a PITA rigamarole for decades.
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From: Texas
Ok, much scraping. Actually found part of the tag plastered to third member. Didn't see it before.
Code starts with WDM-CJ
Measured the flange bolt pattern last time had drums off. 3.5" x 2.375", should be big bearing.
So, looks like 28 spline, but with big bearings?
Code starts with WDM-CJ
Measured the flange bolt pattern last time had drums off. 3.5" x 2.375", should be big bearing.
So, looks like 28 spline, but with big bearings?
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
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From: Simi Valley, CA
It could have the large ball type axle bearing, or the tapered roller axle bearing/seal combination, spline count makes no difference.
1974/79: There's no way to know without pulling an axleshaft and taking a look-see.
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Cross-Country
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From: Texas
Was worried about that. Unfortunately, truck is my daily driver. Taking it apart, seeing whats there, internet and message boards, ordering parts, putting it together week later - Not an option.
Threw the dice on a bearing set that matches up for large bearing 28 spline. Hopefully that does it, if not will have to put it together with whats there and try again next week.
To make sure I'm clear, and do appreciate your time, is there an additional seal that I will definitely have no matter which bearing set is already there? Sorry for asking, but all videos and info I'm finding apparently do not cover all combinations. Most people with trucks go for 31 spline axles and have large bearings or cars with 28 spline and small bearings. Can't find anything that matches my setup.
Threw the dice on a bearing set that matches up for large bearing 28 spline. Hopefully that does it, if not will have to put it together with whats there and try again next week.
To make sure I'm clear, and do appreciate your time, is there an additional seal that I will definitely have no matter which bearing set is already there? Sorry for asking, but all videos and info I'm finding apparently do not cover all combinations. Most people with trucks go for 31 spline axles and have large bearings or cars with 28 spline and small bearings. Can't find anything that matches my setup.
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Well, it's good to know at least!
But to answer your previous question, NO, you do not use a separate seal for both types of bearing. Only the sealed ball bearing type gets the inner seal. The tapered Set-20 bearings you have do not use a separate inner seal because they need to be lubricated by the gear lube in the differential.
The seals in your case are part of the bearing assembly and are always now part of the purchase. I don't remember if you could ever buy them separately (I used to think you could) but I have not seen a listing for anything but the "Set-20" which is bearing, race and seal all in one.
Paul
But to answer your previous question, NO, you do not use a separate seal for both types of bearing. Only the sealed ball bearing type gets the inner seal. The tapered Set-20 bearings you have do not use a separate inner seal because they need to be lubricated by the gear lube in the differential.
The seals in your case are part of the bearing assembly and are always now part of the purchase. I don't remember if you could ever buy them separately (I used to think you could) but I have not seen a listing for anything but the "Set-20" which is bearing, race and seal all in one.
Paul
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From: Simi Valley, CA
But to answer your previous question, NO, you do not use a separate seal for both types of bearing. Only the sealed ball bearing type gets the inner seal.
The tapered Set-20 bearings you have do not use a separate inner seal because they need to be lubricated by the gear lube in the differential.
The seals in your case are part of the bearing assembly and are always now part of the purchase.
I don't remember if you could ever buy them separately (I used to think you could) but I have not seen a listing for anything but the "Set-20" which is bearing, race and seal all in one.
The tapered Set-20 bearings you have do not use a separate inner seal because they need to be lubricated by the gear lube in the differential.
The seals in your case are part of the bearing assembly and are always now part of the purchase.
I don't remember if you could ever buy them separately (I used to think you could) but I have not seen a listing for anything but the "Set-20" which is bearing, race and seal all in one.
I don't know how auto parts stores sell the bearing and/or seal, because I never bought either from them.
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