Problem with rear diff LS swap

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Feb 5, 2011 | 07:59 PM

Vettestir

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Problem with rear diff LS swap

Let me start out by stating I am by no means a mechanic. So I decided to add an eaton posi to the rear of my 2002 F250 with a Ford 10.5/373 rear (with the help of a friend). So when we added the posi and took out the old "carriage", we also removed the pick up for the rear ABS speed sensor. Now of course my speedo is funky and the ABS light stays on. I've done searches and don't see anyone mentioning this problem. Did I do something wrong? Is there a bypass for the rear ABS sensor? I'm at my wits end and surely hope someone out there can help. Thanks in advance!

Feb 5, 2011 | 08:27 PM

2002 F350V10

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Somehow you must put the pickup back on the unit. The rear abs sensor is a very critical input which controls the abs, speedometer, and plus the trans shift, possibly more. When the sensor was bad on a truck of mine, even the check engine light was lit up, along with the abs light, the dead speedo , and trans shifts were off and hard.

Feb 5, 2011 | 11:56 PM

99f350sd

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From: Lyndonville, Vermont

You don't remove any of the speed sensor stuff. It all goes back on..
You are supposed to use the same ring gear it gets bolted to the diff you have...If you pull the tone ring off ford says get a new one...

Dick

Feb 6, 2011 | 08:22 AM

Vettestir

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The "tone ring" is cast as part of the ford unit which you replace with the LS? That said, I had to put the unit back together without the tone ring. I can't believe I would be the only one encountering this problem. Did I purchase the wrong eaton posi and there's another one out there that has the tone ring included?

FYI - I did reuse the original 373 ring and the tone ring was not attached!

Feb 6, 2011 | 09:41 AM

Zedrive

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From: Maple Ridge, Canada

I don''t think the original carrier has the tone ring cast in. Look closer at the original carrier the ring is a separate piece.

Feb 6, 2011 | 06:17 PM

99f350sd

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From: Lyndonville, Vermont

Quote:

Originally Posted by Zedrive

I don''t think the original carrier has the tone ring cast in. Look closer at the original carrier the ring is a separate piece.

He is correct. You need to buy a new ring put it on and you will be fine.. I wouldn't drive the truck until you do this as you could damage something. No one puts a new diff in with out keeping the ring in there.

Dick

Feb 7, 2011 | 09:17 AM

Vettestir

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I'm Rockin and Rollin

Quote:

Originally Posted by Zedrive

I don''t think the original carrier has the tone ring cast in. Look closer at the original carrier the ring is a separate piece.

Thank goodness! After three sets of eyes and looking at the original carrier myself... 4 times. I read your post and said what the hell and wacked the tone ring with a hammer. Two hits later and the thing fell right off. Within 2 hours I had the rear pulled, the tone ring installed, and I was on the road. I'm lookin good and feelin the same. Thanks so much!