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Discussion Starter · #1 ·
This is one of the few places that people really know about swaping axles, so here is a question.

I'm going to swap out the rear end in my 87 toy p/u.
I will be using this truck for rally type races, lots of on/off full throtle and side to side loads.I'm told that the 7.5" will break do to the shock loads that will be put on it.

I will only be using a LSD not a locker, 4.56/4.88 gears and 26 to 33 inch tires, low gears and lots of revs to make the power. Fiberglass fenders (+5") for wider tires.

I currently have an explorer rear for my YJ and began looking at using this type in the truck but the offset is something that would have to be addressed because of clearance with the gas tank, here are my questions.

Toy 8" 30 spline, 3" wider than stock
Ford Explorer 8.8" 31 spline w/DB 4.5" wider than stock
87 YJ Dana 35 non c/clip (free!)
Lincoln MKVII/ V8 8.8 28? spline w/DB 6" wider than stock.

I'm leaning towards the lincoln I can play with the back spacing a little to help, and its centered.
As always I appreciate your comments

Bob
 

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Ya I like the 8.8 but for what you want to do with it. 9" all the way.
 

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... toyota questions here? ... /ubbthreads/images/graemlins/tongue.gif

Ford 9" is the way to go.
At least as strong as a D-44 with more ground clearance, more gear options, and off the shelf disc brakes (Lincon Town Car).

Any good street rod shop can narrow one for you, if you can't find one out of an early Bronco.
They are easy to narrow, cheap, everybody makes something for them and it all works.

That rear end should make some Jeep owner a fine addition after that toyota gets scrapped on the trail /ubbthreads/images/graemlins/blush.gif
 

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Re: O/T Rear Diff strength comparison

I know that you did not mention a Ford 9, but I will suggest that take one into consideration.

I think that the Ford 9 is the way to go. As was said, you can get good ground clearance, especially if shaved. You can get anywhere from ~28 spline shafts on up to the big bad 40 spline shafts.

You should check this link out to see what the Ford 9 has to offer...

Sunray Engineering -- Why nine?

By the way, I am running a ford 9", with 60"WMS, clearanced, spooled, and 35spline shafts in the rear of my CJ7.

-- Mike
 

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Here are the relative strengths of several stock axles with continuous output torque ratings - Strongest to weakest . . .

Ford 9" nodular carrier 31 spline - 1,420 lbft
Ford 9" standard carrier 31 spline - 1,390
Ford 8.8" 31 spline - 1,360 lbft
Ford 9" 28 spline - 1,340 lbft
Ford 8.8 28 spline - 1,250 lbft
Dana 44 30 spline - 1,100 lbft
Dana 35 - 870 lbft

I'm not sure about Toy axles but I would guess they fall somewhere between the Dana 44 and the Dana 35
 

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Why would a 30 spline D44 have a lower strength than a 28 spline 8.8 or 9"?
 

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Another option is a Grand Wagoneer dana 44 if your front is 6 lug.
 

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[ QUOTE ]
Why would a 30 spline D44 have a lower strength than a 28 spline 8.8 or 9"?

[/ QUOTE ]

There's a lot more to axle assembly strength than just the shafts. Compare the carrier and gearsets.
 

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Discussion Starter · #10 ·
Yeah I got a yota also! You would be suprised that most people know nothing about swapping axles.
I called All Pro so called toyota experts, ans they told me toyota never made a 8" for a 2wd. WRONG!

A 9" ford would be the way to go but I was looking for somthing the would only have required new spring pads, that about the limit of my skills and wallet right now!

I'm going to up grade to a stronger toy axle, its stronger than my 7.5 and will be cheaper for the R&P.

Thanks guys for the information,
Bob
 

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[ QUOTE ]
Why would a 30 spline D44 have a lower strength than a 28 spline 8.8 or 9"?

[/ QUOTE ]
8.8 and 9 Ring and pinion dwarf the 44s. Also 8.8 has 3.25" tubes vs. 2.75" on the 44. I've got an 8.8 and love it, laying next to a 44 the 8.8 looks HUGE!! The 31 splined 8.8 is actually closer in strength to a D60 than a D44.
 

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Sorry dude, spent all my money on my jeep, don't have a digital camera. Anybody else got pics for him? I do speak the truth though. Helped my buddy Tim rip out the D44's from a Grand Wagee and after comparing the rear 44 to my 8.8 he's already talking about doing something different. Aaron
 

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the one ton toy had a 8 inch. The toy 8 is bigger and stronger than the 44. The dana 35 is a joke. Go find you a dana 60. That would never break, but then the weight and size would kill you.
 

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web wheelers unite!
when is the last time any of you actually broke a ring gear in a 44 or 8.8 or anything larger than a dana 30?
I broke a dana 30 ring gear once..pushing 350 hp with a welded diff, horribly set up gears and 35" boggers.
Thats the only gear set I have ever broken(except the ones I pushed the bottom into)
my point is...
I don't care how big the ring gear is, an 8.8 ain't no 14 bolt. AXLE SHAFTS are the weak link in an axle.
for rally races, I'd go with the thick tubes and the ford 8.8
 

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Rockcrusher - good info on your chart.

I assume these are standard, stock axles?

Where does the D-60 come in?

And -- the aftermrlet axles - like Superior - how much stronger are they?

One thing to consider - on the trail, a broken axle is easier to swap out than a R&P or locker. The axle acts as a fuse, protecting the rest.
 

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[ QUOTE ]
One thing to consider - on the trail, a broken axle is easier to swap out than a R&P or locker. The axle acts as a fuse, protecting the rest.

[/ QUOTE ]

Very sage advice there Rich,,, I often think that of U joints myself, my weak link to protect the drive train /ubbthreads/images/graemlins/thumbsup.gif
 

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Rich ...
Those numbers are for OEM axle assemblies. I believe the stock 35 spline Dana 60 is rated at around 1,500 lbft of continuous torque. I don't have numbers for axles with aftermarket shafts

I forgot to mention the AMC 20 axle. The CJ version with 2 piece shafts and wimpy tubes is probably a bit weaker than a Dana 44. The rest of the 20's are on a par with the 28 spline 8.8's
 
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