Narrowing an Exploder diff

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Dwayne
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Narrowing an Exploder diff

Post by Dwayne »

Wouldn't it be nice to just go down to the local wreckers and pick up a disc braked, 31-spline for bugger all. Heck, might as well grab the one with the 3.73 lsd centre if I'm going to fork out a whole $250.

So I did.

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The 96-02 Ford Explorer rear diffs have an offset centre, with longer axles used on the LH side. If you narrow the left housing tube by 2-7/8" you can use two passenger side axles for a total width of only 56-1/2" (vs 57-1/4" in a 64-66 Mustang).

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Charbel
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Re: Narrowing an Exploder diff

Post by Charbel »

Disc Brakes vs C Clip axles? ?
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Dwayne
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Re: Narrowing an Exploder diff

Post by Dwayne »

Certainly the weakest point, but haven't heard of many people actually breaking the 31 spline axles.

In the highly unlikely event that they do break an axle, the disc brakes will still hold them in.
Last edited by Dwayne on Fri Jul 20, 2018 7:26 pm, edited 1 time in total.
Pinto-Pete
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Re: Narrowing an Exploder diff

Post by Pinto-Pete »

What is the size of the ring gear..?
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Charbel
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Re: Narrowing an Exploder diff

Post by Charbel »

I think they are an 8.8". Like the GM C Clip diffs they are a decent diff (unless they are the useless 7.5" version) just axle retention is shiite. If you are shortening the diff then you can re-weld a big bearing flange on rather than the 8.8 flange.

Unlikely to break an axle, more likely that the clips holding the axle in fail. Certainly renew them when you put back together.
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Dwayne
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Re: Narrowing an Exploder diff

Post by Dwayne »

The axles are retained by these c-clips

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The early 28-spline drum braked fox body mustangs sometimes broke axles and the whole wheel and axle would exit the housing. That is as bad as it sounds.

I think cars running I'm the 10's in the US require c-clip eliminators to be fitted. These make the axle captive at the housing end in a failure.

It's hit or miss what the 28-spline axles are like, with some snapping and others running into the low 9's with 5,5000rpm launches on drag slicks with no issues.

In disc brake setups, the rotor and caliper retains the axle if it breaks.
Charbel
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Re: Narrowing an Exploder diff

Post by Charbel »

I got 3 Clippers in the family and very familiar with those delights.

You also get a lot of axle float, that will push the pistons in the calipers in or out, I've gotten used to (as well as the wife) pumping the brake pedal every now and then.

Like I said. If you need to shorten, seriously consider changing to a bearing on axle flange.
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Dwayne
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Re: Narrowing an Exploder diff

Post by Dwayne »

But wouldn't that also require new axles and brake kit? That would defeat the whole purpose of the project.
Charbel
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Re: Narrowing an Exploder diff

Post by Charbel »

I guess if the purpose was to do a cheap disc brake conversion sure. But if wanted to build a cheap, pretty tough diff then maybe not.

The 8.8" is a pretty strong diff and its getting more support in the aftermarket. Couldn't comment on the nitty gritty of the install but the likes of strange, moser, currie etc pretty sure do housing ends with the 8.8" bolt pattern but with a 3.15" big bearing. You'd still need new axles to suit, but brakes should go on.

C clip eliminators are a waste of time, in most cases anyway. Better off going the above route than doing eliminators.

C clips are fine for the street probably ok for drags too, certainly would be doing any spirited hillclimbs or circuit stuff with them. Just know the short comings of the diff.
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Dwayne
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Re: Narrowing an Exploder diff

Post by Dwayne »

Just a typical street car, not expecting to have a bulletproof rear end for a race car for only $350.

It seams to be the 4x4 guys that break the axles so is it the sideways forces thacause the issues? That would fit with your hillclimb and circuit comment.
Last edited by Dwayne on Sat Jul 21, 2018 9:50 pm, edited 1 time in total.
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