Differential

[BLACKMARAUDER04]

I informed the group last week that my Differential had expired.
Several members said to use a CV or GM unit.
Well I have found out the internals are not the same.
The locker used in the Marauder is Marauder specific to handle the extra torque. Ford no longer makes this part for the Marauder (the CV's didn't fit). It is a aftemaket unit. The bearings are also Marauder Specific as the CV's were also wrong.

[Logizyme]

I call BS.

Its a ford 8.8.

Ford might have different part numbers for the differential carrier, might even have different numbers for the bearings too, but they are 100% compatible.

Obviously the gear ratio is not the same.

All ford 8.8 carriers are cross-compatible, mustang, explorer, f-150, crown vic, ranger, even IRS.

The bearings really should be replaced with the carrier, in fact I would go as far as to say you should do a full rebuild kit, bearings, seals, ring bolts, pinon nut, crush washer and shims.

One thing there is though is the spline count. the 8.8 comes in two different spline counts, the 28-spline and the 31-spline. the 28-spline was used in panthers untill early 2005 model year cars. after that panthers got 31-spline. a 31-spline carrier from a 2005-up CV/GMQ would not be a direct fit as your axles are 28-spline.

[SpartaPerformance]

Shennanigans its an 8.8" all solid axle 8.8's are identical internals regardless of vehicle until 2004. So I will say again. PM me with what you need and I'll get you prices. I will check here again by 11:30pm EST tonight

[RacerX]

Ford 8.8 1983 to 2010 rear differentials are interchangeable. I'm pretty sure...

[Curless]

Nope, you are wrong. I build them all of the time...Message Tommy at Sparta, get the parts, fix it be done.

[martyo]

Well I have found out the internals are not the same.

What was the source of this misinformation?

[Vortech347]

Ford 8.8 1983 to 2010 rear differentials are interchangeable. I'm pretty sure...

This..

Whoever you spoke with is an idiot and should have their mouth stapled shut.

[tbone]

I have a standard ring and pinion in perfect condition if you want it. Just pay shipping.

[BLACKMARAUDER04]

All internal parts were replaced. The ring and pinion were broken in half.
My local Ford / Lincoln dealer is doing the work. I've gone there since
moving to the LA area in 1980. My service writer told me that the carrier from the CV does not fit. He ordered a non Motorcraft part for it as Ford discontinued the part. Maybe Ford updated the part for the 2004 cars like they did the transmission. I have no reason to doubt what he is telling me, as it is the only part Ford will not cover under warranty.

[Curless]

All internal parts were replaced. The ring and pinion were broken in half.
My local Ford / Lincoln dealer is doing the work. I've gone there since
moving to the LA area in 1980. My service writer told me that the carrier from the CV does not fit. He ordered a non Motorcraft part for it as Ford discontinued the part. Maybe Ford updated the part for the 2004 cars like they did the transmission. I have no reason to doubt what he is telling me, as it is the only part Ford will not cover under warranty.


Not trying to be a dick or anything but you are being lied to....sorry no arguing....the only thing that may be is that the posi in 28 spline may not be available any longer...

[fordmike65]

All internal parts were replaced. The ring and pinion were broken in half.
My local Ford / Lincoln dealer is doing the work. I've gone there since
moving to the LA area in 1980.
Los Angeles? ? If so, pm me.

[RF Overlord]

What they all said ^^^ : an 8.8 is an 8.8 and they are all interchangeable, even the 2005+. The only difference is that 2005+ supports 31-spline axles instead of 28.

If your dealer is telling you otherwise, find another dealer.

I had one tell me that "someone" must have put a Crown Vic rear end in Mary's car as it had 28-spline axles and all Marauders had 31. :shake:

[lifespeed]

Probably he is referring to the discontinuation of 28 spline limited slip carriers. Would have been the appropriate time to upgrade to 31 spline and a Ford Racing diff with carbon clutches. Too late now, I suppose.

Remember this for next time. I'm sure you were informed of this by those on the forum before allowing your dealer to "do things his way". Live and learn.

[Vortech347]

Again, unless your pushing 450+ on street tires or constantly running slicks spending extra money for new axles and a completely new carrier is a complete waste of money unless all those components are already damaged.

31 spline carrier housings are not "stronger" They are the exact housing. The ONLY difference is the spider gears that the axles slide into have 31 splines instead of 28.

[lifespeed]

Again, unless your pushing 450+ on street tires or constantly running slicks spending extra money for new axles and a completely new carrier is a complete waste of money unless all those components are already damaged.

31 spline carrier housings are not "stronger" They are the exact housing. The ONLY difference is the spider gears that the axles slide into have 31 splines instead of 28.

That stuff is pretty much always damaged after 100K+ miles, as is the OP axle assembly guts. Pointless to buy new 28 spline stuff, regardless of horsepower. And the carrier isn't available anyway. Yeah, I know how 31 spline axles are inserted into the carrier - through the side gears. Carriers are typically replaced for wear, not because they exploded in a dragstrip launch.

It's not like the 28 spline parts are cheaper . . .

[Logizyme]

the 31- and 28-spline hosings are different because the spider gears are slightly different. I cant recall exactly but I think you can swap spider gears but they dont fit quite right in the opposite housing.

and ford used the 31-spline axles way before 04/05, they go way back to the 90's at least, and they've always been the heavy duty option as compared to the 28-spline. They just used 28-spline in panthers untill 2005 and 31-spline in panthers from 2005 on.

They only reasons I've seen to replace a carrier are for upgrades or if the spider gears/crosspin are damaged/worn. Seen countless broken spider gears. never seen the housing itself worn on an 8.8.

28-spline is allot cheaper if you can keep your old axles $150 x2 = $300 for new axles.


I have a standard ring and pinion in perfect condition if you want it. Just pay shipping.

By perfect condition you mean brand new? because if its used it'll almost always make noise when put into a new build. When reusing a R&P you should duplicate the backlash and spacing that it had before removal, if not it'll make gear noise and wear more. just saying.

[BCMARAUDING]

Any of my BC Canada friends know of any good Diff shops in the Lowermainland?

[GreekGod]

The OEM differential in my 2003 MM was not repairable because Ford had discontinued the replacement 28 spline side and pinion shaft gears. The updated gears had a different tooth profile than the OEM, and were not interchangeable.

This was a running change, and I can't swear to it, but if my memory is correct, they also changed the case, so that it was also obsolete, and not interchangeable.

I eventually replaced it with a 31 spline Eaton Detroit Locker. It took me a year to get used to the differential noise & backlash. If I had it to do over, I would have used an Eaton Truetrac.

==========

[Vortech347]

Ahhh... I've taken an older sub 2000 difs and swapped out the spider gears before. From 28 to 31. I'll remember this if I do any of the newer stuff.

[vegasmarauder]

I have a related question for someone who does differential work. The 2003-2005 rear end housing from Ford has been discontinued (and carrier) and replaced with the 2006-up housing. The notation says that you must use 31 spline axles and carrier) in the new housing. If all the parts will interchange between 28 and 31 what's the difference. The reason I'm asking is that I can get a nearly new 2006-up housing for cheap and was wondering if it is worth it.

I understand about having to change the center section over to fit 31 spine axles in a formaerly 28 spline diff.

Thanks..

[justbob]

I have upgraded existing 28 spline diffs to 31 spline simply by changing the spiders, sliding in the new axles and oil.


Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"

[Vortech347]

I have upgraded existing 28 spline diffs to 31 spline simply by changing the spiders, sliding in the new axles and oil.


Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"

Yup me too. Guess they changed?

[justbob]

Yup me too. Guess they changed?

Maybe? IIRC All four gears had to be changed out for it to work, not just the sides. I also forgot to add that you do in fact need the Cobra spring when doing a spider transplant, but that completes it.

Maybe that is the difference in gear pattern? Idler gears have to stay with their sides and they are not interchangeable between the two different splines? Been awhile.


Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"