Replacing rear differential...

Synchros shot? Weird noises while shifting? Not sure what needs to be replaced?
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six
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Replacing rear differential...

Post by six »

So, I was wondering...

My Crown Vic has a 3.27:1 rear axle with an open diff. How difficult would it be for me to switch it to a 3.73:1 limited-slip? Is it something that I can tackle myself? I can get all the parts... it just a matter of installing it...

Thanks.
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mad_finn
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Re: Replacing rear differential...

Post by mad_finn »

Basicly its guite simple... get new axel wich has been used in crown vic, then drop the old axel, and put new on it... basicly "bolt on" thingy...

here is link how to do it IF it has leaf springs, allthough, its not much harder if it has any other common springs...
http://www.associatedcontent.com/articl ... e_how.html
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Re: Replacing rear differential...

Post by IMBoring25 »

We swapped the 3.27 open in my Grand Marquis for a 3.55 locker by swapping the whole axle for one out of an '85 Town Car. The problem with the whole-axle swap for six's application is that the 3.73 was never offered in the Panther platform. A Marauder, Town Car, or some years of P71 would have a 3.55 locker available, but 3.73 was never offered.

That makes it a matter of changing the ring and pinion and adding the clutch packs. I've never really looked into it, but I've understood it's not too bad to do, though you need to make sure you get the gears meshed correctly. Also remember to change the speedometer drive gear, unless they've changed where they do the speedo pickup.
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six
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Re: Replacing rear differential...

Post by six »

I can get the gears and trac-lok diff pretty easy. I'm planning on letting the pros do it because I know something will go wrong if I do it...

The 2003+ Panthers don't use the speedo gear anymore. Speed info is taken from the PCM, so I would need to have a reflash to correct my speedo after I change to 3.73 gears.
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Re: Replacing rear differential...

Post by Rope-Pusher »

Some folks might call it an easy swap, but I'd say that's a matter of a pinion. If you swap in a new diff carrier with limited slip and a new ring and pinion set, you may need to play with it (shims) to get the correct bearing preload and to get the pinion gear correctly engaged with the ring gear (down on one knee, open ring box in hand, etc.). If you don't, it can end up being quite a mesh.
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Re: Replacing rear differential...

Post by theholycow »

Yep, I've read plenty of threads for people who want to DIY and it often looks like a big hassle. Some of them gave up and took it to a pro.
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six
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Re: Replacing rear differential...

Post by six »

Rope-Pusher <-- He's funny :lol:

"...quite a mesh" hahaha
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Re: Replacing rear differential...

Post by LHOswald »

i thought the "a pinion" one was pretty good as well
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Re: Replacing rear differential...

Post by noob5,000,000 »

That's one of those things I'll probably never attempt to DIY. Setting the gear lash and stuff is too intimidating.
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