8.8 diff bolts into v6?

Zane Cunningham

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I bet this has already been covered but I can't find anything definitive on it.
I'm looking at buying just the 8.8 gears and then a housing or case separately(don't ask, I'm broke and buying them used). Then putting that in my current rear end (2000 v6). It has a t5 and from what I've read the driveshaft will fit up but do the axles bolt in correctly? Or is it smarter or easier to get an entire rear end?
Also if there's anything else I have to worry about swapping, speedo or wiring or anything I have to move/delete
 

Randall Garner

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Your V6 housing is 7.5" so trying to stuff 8.8 goodies in will not work. You need a complete 8.8 from 94-04 and then think about gearing . Most 8.8 out of GT's. Have a 3.27 gear. So if your V6 has the 2.73. that's already a decent change in gear ratio. The 8.8 bolts directly in. Your current rotor will work. But you'll need the year of rear GT(V8) caliper and support if the rear you find doesn't already have the brakes. Upper and lowers you can reuse or get aftermarket. The GT 8.8 still used 28 spline axles. If your lucky might find the 03-04 mach1 rear. Some came with 31. Most had limited slip difs. As far as speedo you might need to take to a speedo shop they can change your gear on the transmission. To recalibrate your speedo. Unless the car your getting the 8.8 has similar trans. . take the speedo drive. It may get you close enough
 
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Zane Cunningham

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Your V6 housing is 7.5" so trying to stuff 8.8 goodies in will not work. You need a complete 8.8 from 94-04 and then think about gearing . Most 8.8 out of GT's. Have a 3.27 gear. So if your V6 has the 2.73. that's already a decent change in gear ratio. The 8.8 bolts directly in. Your current rotor will work. But you'll need the year of rear GT(V8) caliper and support if the rear you find doesn't already have the brakes. Upper and lowers you can reuse or get aftermarket. The GT 8.8 still used 28 spline axles. If your lucky might find the 03-04 mach1 rear. Some came with 31. Most had limited slip difs. As far as speedo you might need to take to a speedo shop they can change your gear on the transmission. To recalibrate your speedo. Unless the car your getting the 8.8 has similar trans. . take the speedo drive. It may get you close enough
Awesome thank you, my current diff is 3.27
I'm still a little confused as if it bolts in correctly why would I need to replace anything else?
I'm pretty much asking can I replace just the differential instead of the entire rear end and have it work? Or do the splines not match up as you said?
 

Randall Garner

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Is your rear a 7.5 or a 8.8 now I'm confused. The axles are not exactly the same length and the brakes do not work from V6 to V8. Only the rotors. 7.5" and 8.8" differential are completely different sized. That's why if you go 8.8. You need the housing and axles . If your keeping it V6. Just upgrade your gears and differential. To limited slip or posi for the 7.5". The axles to hold up to V6 even a mild V8 the size is in the description 7.5" or ,8.8. I got a 8.8 out of a 03 and the only part that was the same between 6 and 8 are the stock rotors. Different caliper and caliper bracket. 1/2" wider each side so the gt offset brakes fix the alignment. True everything external to the housing after that works from your current car
 
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Warhorse Racing

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Your 2002 V6 came with a 7.5" rear end that uses 28-spline axles. You would need a 7.5" differential and gears. An 8.8" differential and gears won't fit in your housing. If you check with Mustang parts suppliers, you will see that they sell rear brake calipers that fit 94-04 GT/V6 Mustangs. Here's an example:


You will also see that they sell 28-spline axles for 99-04 Mustang GT/V6 models. Here's an example:


Those axles are listed as fitting 99-04 7.5" & 8.8" rear ends.

Keep in mind, 94-98 Mustangs had different axles and a different rear end housing. If you are looking for a complete swap that will work with your OEM V6 front brakes, a 99-04 GT swap is your best option (Bullitt & Mach 1 Mustangs had larger rear brakes).

This guide might also be helpful:

 

shovel

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Installing gears in an axle requires specific tools and knowhow, it's not a driveway job for somebody new to this nor is it any kind of job for someone who describes themselves as broke.

Replacing the whole axle is comparatively very easy and can be done with standard tools, though I'm just being real here the way you're asking this question.. uh.. get help from somebody who's done it already OK? You and other people die if you get this wrong.

The only factory axle with deeper gears that will bolt into your car is from a 2003-2004 Mach 1 . It's a nice upgrade I've done it on my wife's 2002 V6 but you should be aware that in terms of the gears themselves it's only a 8.5% change, which is subtle and it seems like most people who start collecting mods like pokemans hate subtle changes and want to go full R on everything. So if you only go 3.27 to 3.55 you better be real sure that's exactly what you want.

So your other option is to find a whole axle that's already been swapped to 3.73 or 4.1 or whatever ratio you ultimately want. Which costs real money. And you said you're broke. So.. I don't know do whatever, people just ignore advice and do whatever they want anyway.

If you want your speedometer to read correctly you'll need a tuner for that, thankfully with 99+ you can do that with a tuner it's much more of a P.I.T.A. with earlier V6's
 
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Zane Cunningham

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Thank you guys all for the responses, I'm still relatively confused but I now know the 8.8 can't be put in a v6 without changing out the entire rear axle/end which is what I needed to know.
 

96blak54

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Installing gears in an axle requires specific tools and knowhow, it's not a driveway job for somebody new to this nor is it any kind of job for someone who describes themselves as broke.

Replacing the whole axle is comparatively very easy and can be done with standard tools, though I'm just being real here the way you're asking this question.. uh.. get help from somebody who's done it already OK? You and other people die if you get this wrong.

The only factory axle with deeper gears that will bolt into your car is from a 2003-2004 Mach 1 . It's a nice upgrade I've done it on my wife's 2002 V6 but you should be aware that in terms of the gears themselves it's only a 8.5% change, which is subtle and it seems like most people who start collecting mods like pokemans hate subtle changes and want to go full R on everything. So if you only go 3.27 to 3.55 you better be real sure that's exactly what you want.

So your other option is to find a whole axle that's already been swapped to 3.73 or 4.1 or whatever ratio you ultimately want. Which costs real money. And you said you're broke. So.. I don't know do whatever, people just ignore advice and do whatever they want anyway.

If you want your speedometer to read correctly you'll need a tuner for that, thankfully with 99+ you can do that with a tuner it's much more of a P.I.T.A. with earlier V6's
Does being broke or wanting to be thrify imply ignorance to a hobbiest? Because your post points this out.
 

shovel

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Does being broke or wanting to be thrify imply ignorance to a hobbiest? Because your post points this out.

Calling the rear axle a "housing or case" implies that they aren't experienced or knowledgeable yet. I didn't call OP stupid, but I do expect they're not experienced and I'm communicating accordingly. What is your point exactly.
 

lutter94

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This has been painful to read.

You have a 7.5" rear axle housing, you can swap the rear axle to an 8.8" rear axle housing. 8.8 parts won't fit inside a 7.5 rear end. Your brakes will swap over to the 8.8 no problem. Your control arms will bolt up to the 8.8 no problem.

Source the 8.8" "complete rear axle" swap gears or whatever you need to do, and then swap rear ends.

End of conversation.
 

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