Rear Differential question

[Kevin2011]

My old 94' F-250 has a limited slip rear end. It is fantastic for plowing. I am not convinced yet that my new 99 F-350 is the same. I have not driven it enough to be certain. Does anyone know, if it turns out to be a regular differential, if I can convert it over to a limited slip with just a gear change or do I have to replace the entire unit.

Thanks

[sniper_101]

Originally Posted by Kevin2011

My old 94' F-250 has a limited slip rear end. It is fantastic for plowing. I am not convinced yet that my new 99 F-350 is the same. I have not driven it enough to be certain. Does anyone know, if it turns out to be a regular differential, if I can convert it over to a limited slip with just a gear change or do I have to replace the entire unit.

Thanks

I could be wrong, but I do believe I read the 10.25" carrier will work in the 10.5", but not the other way around. If so swap the current ring onto the other carrier, reset all clearances/lash and plow away.

If I'm wrong on this, pretend I was never here! Someone smarter will chime in shortly.

[mustangman02232]

if you have the money, put a detroit true trac in it

[forddieseldoctor]

To change it over to limited slip you need to swap the center carrier for one that has the clutch packs in it.

[PGreenSVT]

I would opt for the ARB air locker or the Eaton E locker over the Detroit locker. That would allow you to turn it on an off as needed. Detroit's can be a bit of a nuisance on the street. Of course a clutch bases system like Ford's will be cheaper but doesn't lock up very well IMO.

[jbev59]

The ARB and EATON lockers are NICE but they are exspensive . I would find a factory possi ford carrier . I think they are called trac loc

[Kevin2011]

I noticed in the snow that both spin fairly easily. But on dry tar I was getting into traffic and nailed it to get out of the way and I spun out on 1 tire for a while. So I am still uncertain if I have posi.

[Bad Night]

Originally Posted by Kevin2011

I noticed in the snow that both spin fairly easily. But on dry tar I was getting into traffic and nailed it to get out of the way and I spun out on 1 tire for a while. So I am still uncertain if I have posi.

One wheel peel doesn't mean it's not a posi , could have worn cluch pack . Is there a tag on the rear end ? Otherwise pull the cover ant take a peek

[Kevin2011]

Ok thanks I will check. umm er what would the tag say - "posi"??

And if I were to open it up (which I need to do to change the oil) what am I looking for to indicate it a posi?

[Bad Night]

Well my dana80 says ls . Don't know about the Sterlings . Well it will have the have clutch packs , I can't remember if you can see them without pulling the center section now that I think of it . If I remember correctly , if it's a posi . if you spin the passenger tire forward the drivers tire will turn forward as well , an open rear end the drivers tire will spin backwards .