Rear axle choices Ford 9" or 8.8" or other? (2008-2022 bump)

[qwkswede]

Yep, this is how the math was working in my head too. Though I was just going to have the 31 spline axles shortened and resplined for $100. Empty 9" housings are $600 from Moser. Differentials, especially the aluminum ones are pretty expensive too. I can see how it pretty quickly adds up to John Lane's number. Maybe all in for about $2000 if I do the fab work myself. But I wasn't planning to spend that much either.

I disagree. Using prices I was quoted from over there.
Explorer Axle (junkyard) $100?
Narrowing (self) $0
Axle shafts (Moser) $315
Ford Racing clutch pack $115
Diff Girdle $175
ARP stud kit $20
And that already has 31 spline diff, LSD and rear discs. With Moser shafts that axle will take more than anyone on here can throw at it.

 

[John V outside agitator]

Yep, this is how the math was working in my head too. Though I was just going to have the 31 spline axles shortened and resplined for $100. Empty 9" housings are $600 from Moser. Differentials, especially the aluminum ones are pretty expensive too. I can see how it pretty quickly adds up to John Lane's number. Maybe all in for about $2000 if I do the fab work myself. But I wasn't planning to spend that much either.

Something wrong with the Toyota option?

Or do you just want to spend lots of money?

 

[wingnutty]

If you locate a 9 " out of a pre 80's van some years had offset diff third member or one axle tube shorter tan other
this is helpfull in narrowing the rearend if you locate 2rears and use the shorter 2 axles and cut and reweld 1 flange =budget strong rear some of the vans had a locker diff and various gear ratios you want the 31 spline
drawback they dont have rear disk the 8.8 has less ease in gear or pumpkin replacement but is readaly availabil
w/rear disk at a lighter housing

 

[BB-Q]

If you locate a 9 " out of a pre 80's van some years had offset diff third member or one axle tube shorter tan other
this is helpfull in narrowing the rearend if you locate 2rears and use the shorter 2 axles and cut and reweld 1 flange =budget strong rear some of the vans had a locker diff and various gear ratios you want the 31 spline
drawback they dont have rear disk the 8.8 has less ease in gear or pumpkin replacement but is readaly availabil
w/rear disk at a lighter housing

I often hear this touted as a reason for going to a 9". If you do your calculations correcty and know the indended purpose for your vehicle just how often will you change the axle ratio?

My guess is never.

 

[qwkswede]

Something wrong with the Toyota option?

Or do you just want to spend lots of money?

I guess I don't know enough about the Toyota axles. I just like the aftermarket support for the Ford stuff. And the used stuff was plentiful too.

Is there a spool available for the toyota differential? Is it a common differential that I can get 33 spline, or 35 spline axles later if I want them? The 8.8" stuff has all that available.

The plan is looking like shortening the axle and building the car around a 28x10,5" tire, probably on a 15x10 or 15x12" wheel. I could go bigger on the tire size, but I want to run the 10" tire drag classes . And the car should have plenty of traction with that without having to turn over a 31 or 33 inch tire. I won't need to build a ridiculously narrow rear subframe either. And hopefully that means that I can still cruise the car on the street occaisionally if I want to.

 

[JohnLane]

A package of spool and beefier axles for the Volvo axle would be slick. They could be made to go together and therefore bigger axles in the splines where the Volvo axle fails.

 

[nos245na]

Just remeber there are two of the Ford 9 Inch housiings . One is huge and comes out of most trucks and vans. This has a better chance of having 31 spline axles and center, obviously. There is a smaller unit that was in Mustangs and lighter duty trucks and Broncos and such. Could be 28 spline but the housing itself will fit under the car a little better.
Late 70s and some 80s Lincolns had a nine inch with disk brakes but they are huge and heavy and come up less often in the wreckers. They also have tapered axles which cannot be shortened if you choose to go that route. If you are going to build a 9 inch OR an Exloder rear be sure to gusset the 9 inch at least on the inside and if you can afford it on the outside. With the Exploder or late Mustang 8.8 make sure you reweld the tubes to the "chunk" ( or pig or center) and do the roset welds on the housing.
Although the factory disk brake option is great , I suggest going to an aftermarket housing end with the symetrical bolt pattern. This is often called the "lamb" style ends. You can fit the big bearing that way and these tend to be a little better for drag racing. There is also a special bearing available for this end that reduces friction. Even if you go the standard (big Mustang) make sure that the rear is built in a jig and is done by someone who has done it before. By the way, in my opinion , using the stock diff with axles plugged in it as a "jig" is a bad way to do the job. If you put a stock axle in a diff and notice how much play there is in the axle you will understand why I think so. The 8.8 should get the same treatment in a jig-- this is of course after you have welded up the peanut. Many mustang racers use the big 9 inch ends on thier rears and eliminate c clips and c clips eliminators altogether. This is the best way to go if you are going to get serious.
Using the more common ends allows you to use brakes from virtually all of the aftermarket suppliers so this is a big advantage.

A few years ago , guys were using the Toyota stuff for thier VERY light weight drag cars with 4 or 6 cylinder power. There are a few companies that support them with spools and the like. Nowhere near the support for the 9 inch or 8.8 of course. If you are appoaching 3000 pounds with slicks and a transbrake I would probably pass on that approach. You might as well go to the 9 inch because the same mods would have to be accomplished to really make it bullet proof.

For this application, 9 inch is the probably the lightest even with the strong "N" nodular case center. The 8.8 is the "cheapest" but heavier because of the pig center. The Toyata stuff is super light but if you are going to get seriuos about the 10.5 racing it will probably be farthest down on the list of rears to go to.
I hope this helps.
George in DC

 

[rnmdad]

I say strange quick change is the way, then you can cruise to the track on your 2.42s, then run the track on your 5.89s...

 

[mAydAy]

I disagree. Using prices I was quoted from over there.
Explorer Axle (junkyard) $100?
Narrowing (self) $0
Axle shafts (Moser) $315
Ford Racing clutch pack $115
Diff Girdle $175
ARP stud kit $20
And that already has 31 spline diff, LSD and rear discs. With Moser shafts that axle will take more than anyone on here can throw at it.

Narrowing yourself is risky business, just the heat from welding a tube twists/warps them all around. Hell, just heating one spot with a torch at a spot is enough to twist it around. Even fresh out of a jig after being welded in one specifically designed for building 9" rears, a rear that has been welded up has to be straightened, and unless you have a straightening jig (or an idea on making one) you'll be running misaligned, which really becomes a problem with drag/binding if you aren't using a full floating setup, but I guess it all depends on how "Right" you're trying to go with things.

Quickchange's are cool but not really designed for drag racing. You could fit something like a Winter's V8 (More compact version with a smaller ring and pinion) under one of these cars probably with a little work, but a full size quickchange would be hell to fit. A frontloader maybe, but a rear loader almost no change....

(PS if you are looking for a quickchange, buy a Winter's, they're the best ones out there overall. Used to deal with them every day...)

 

[Captain Bondo]

Narrowing yourself is risky business, just the heat from welding a tube twists/warps them all around. Hell, just heating one spot with a torch at a spot is enough to twist it around. Even fresh out of a jig after being welded in one specifically designed for building 9" rears, a rear that has been welded up has to be straightened, and unless you have a straightening jig (or an idea on making one) you'll be running misaligned, which really becomes a problem with drag/binding if you aren't using a full floating setup, but I guess it all depends on how "Right" you're trying to go with things.

Did you get that from google or something? No offence, but you obviously aren't speaking from experience. Either that or you suck at narrowing rear ends.

With no bearing installed in the end housing you can easily verify if the housing is aligned on-axis to the splines by installing an axle and moving it in a circle. It should not be able to touch the bearing housing at it's extreme limits, and clearance should be the same all around. Assuming the axle is straight, and spline wear is even, this is foolproof.

If the axle is not straight or the spline wear is uneven, then you're screwed anyways.

Getting the end housings square is not rocket science.

You can easily check runout at the housing end with a dial indicator by mounting the axle on a couple of stands with the stands placed near the pumpkin and rotating the pumpkin.

I did all of these checks when I narrowed mine and guess what? It was straight. I actually expected that I'd need to straighten it.

All of the whining and naysaying in this thread is pretty weak. BBQ, bigbegum, and myself have all done this and our diffs check out straight. If you haven't done it or can't do it, don't just say it can't be done.

And suggesting using a domestic ford rear end is an "expensive" way to go about getting a strong rear end is one of the goofier things John V has ever come up with. Obviously you can buy some expensive parts for them, but when stock explorer rear ends are holding 500hp all day long... one should consider reality.

 

[John V outside agitator]

And suggesting using a domestic ford rear end is an "expensive" way to go about getting a strong rear end is one of the goofier things John V has ever come up with. Obviously you can buy some expensive parts for them, but when stock explorer rear ends are holding 500hp all day long... one should consider reality.

Oh I was just going from what was quoted for the one 9" Ford axle I know of in a Volvo.
Maybe I'm wrong but it seems the quoted $3000 to $4000
sounds just a little more expensive, and a FAWK of a LOT MORE HEAVY than the under 250 bucks and turning the existing flange ourselves to use stock Volvo wheels, rotor and caliper.

But I'm not so good with higher math.

And since my interests do not include things taking only a few seconds, I assumed the availability of a strong LSD with 4 pinions was important.

Goofy me.
I'll let you boys get back to your fapping.

 

[nos245na]

Hmmm . Interesting.

There are always ways to get things right or close doing things a different way. Naysayer no. Experience yes.
I have pulled a converted truck dana 60 with the 3.5 inch tubes out of a race car that was shaped like a frickin wish bone. Went into the car straight as an arrow. Keep hitting that 8.8 with a stick and a big tire for a couple of years and let me know how straight it is.



Weld the proper braces in and on a cr@ppy stamped sheet metal 9 inch ford, put the big four link brackets on it and its still straight ? I would like to see that happen with production tubes. Maybe if you saw what total junk a production Ford axle is compared to a Mark Williams 40 spline axle (or bigger) then you would be less apt to use it and a factory diff as an indexing tool. Strange stuff is "more loose". Moser is loose as a--well pick your analogy. Thats all there is to it really. An indexing bar going through aluminum busings fit to diff bearing sizes is the "proper" way to do it . It doesnt mean there are not other ways to get it right -- or close. Good grief.
First rear narrowed for a race car --1979

 

[Mueller]

Oh I was just going from what was quoted for the one 9" Ford axle I know of in a Volvo.
Maybe I'm wrong but it seems the quoted $3000 to $4000
sounds just a little more expensive, and a FAWK of a LOT MORE HEAVY than the under 250 bucks and turning the existing flange ourselves to use stock Volvo wheels, rotor and caliper.

But I'm not so good with higher math.

And since my interests do not include things taking only a few seconds, I assumed the availability of a strong LSD with 4 pinions was important.

Goofy me.
I'll let you boys get back to your fapping.

not to nit-pik here John, but that mega-dollar price is ready to bolt-in and go....

if you could supply Toyota rear ends fully loaded and ready to bolt-in @ $250, you'd be shipping them out daily

did Kevin get a direct weight comparison between the stock unit and the Toyota unit??

 

[Janne K]

Did you get that from google or something? No offence, but you obviously aren't speaking from experience. Either that or you suck at narrowing rear ends.

I can't say anything about narrowing one, but the few live axles that we've modifidied for Group F have always bent or twisted in some way after welding and they needed some straightening. We've changed the link/rod mounting plates and welded some extra stuff on them.

 

[Captain Bondo]

Oh I was just going from what was quoted for the one 9" Ford axle I know of in a Volvo.
Maybe I'm wrong but it seems the quoted $3000 to $4000
sounds just a little more expensive, and a FAWK of a LOT MORE HEAVY than the under 250 bucks and turning the existing flange ourselves to use stock Volvo wheels, rotor and caliper.

But I'm not so good with higher math.

And since my interests do not include things taking only a few seconds, I assumed the availability of a strong LSD with 4 pinions was important.

Goofy me.
I'll let you boys get back to your fapping.

8.8's can easily be had for under $500. They also come stock with a clutch type posi, and directly accept the Cobra R carbon/kevlar clutch pack kits at around $140.

Stock 31 spline 8.8's hold 500hp reliably. You need not spend $3000 at this stage. If you want 600-1000 you might have to. That is a small percentage of folks, and if you are playing with that kind of fire your budget had better be just this side of unlimited, because somehow I doubt the toyota diff is going to hold 600+ either without serious work. Costs start to go up exponentially.

So to recap: that is a 500hp reliable diff with a clutch type posi for around $500, give or take, depending on the juinkyard. With any conceivable option for a posi available cheap and easy. Brake upgrade kits are cheap and easy and bolt-in.


Please post again, and miss the point, again. Seriously. Compare apples to apples.

 

[BB-Q]

George, for the sake of argument and comparison, would you know what a 9" weighs, say anrrowed for 10.5 slicks on a 240? I've got maximum offset TTII's in the back of my 142 and will gladly go measure the axle width if you need a comparison. I can't weigh my (reinforced, narrowed and fourlinked) 8.8" at the moment but will gladly do so the next time it's out of the car. It would be useful to get some real figures up here to help stop the constant bitchfest that any valuable discussion on here becomes.

 

[John V outside agitator]

not to nit-pik here John, but that mega-dollar price is ready to bolt-in and go....

if you could supply Toyota rear ends fully loaded and ready to bolt-in @ $250, you'd be shipping them out daily

did Kevin get a direct weight comparison between the stock unit and the Toyota unit??

It was a suggestion of something for the real world where people don't have to narrow and but custom axles, and can do a lot of the work themselves.

But it isn't the received dogma so I'll let it drop, obviously everybody needs Ford 8.8 units.

As for weight I believe I read or somebody has previously said it was in the neighborhood of 20lbs more.

Just as a side note doesn't anybody else find it odd how the measurement is always quoted as "31 splines" or "35 splines."
I checked my soooooper accurate very-nears and I only had a choice of English or metric, could find the button to convert diameters into "splines".

And like so much accepted--but never explored dogma, doesn't seem like anybody like to state what DIAMETER people are starting from and what they are wishing for in any of the 2 major measuring systems used in the world.
Is it that everybody knows how many mm or inches all the axles in discussion are already and I'm just too far behind the times?

 

[John V outside agitator]

George, for the sake of argument and comparison, would you know what a 9" weighs, say anrrowed for 10.5 slicks on a 240? I've got maximum offset TTII's in the back of my 142 and will gladly go measure the axle width if you need a comparison. I can't weigh my (reinforced, narrowed and fourlinked) 8.8" at the moment but will gladly do so the next time it's out of the car. It would be useful to get some real figures up here to help stop the constant bitchfest that any valuable discussion on here becomes.

Tsk tsk tsk, Mark.
Why get all shirty now, and why confuse the issue with real numbers, I've been scolded that I miss the point entirely, lets let it be at that.

Plenty of things here go on for 10, 15 pages without ever stating beginning measurements or ending measurements and doesn't seem to affect discussion, why confuse the issue with boring facts and reasoning?

 

[nos245na]

George, for the sake of argument and comparison, would you know what a 9" weighs, say anrrowed for 10.5 slicks on a 240? I've got maximum offset TTII's in the back of my 142 and will gladly go measure the axle width if you need a comparison. I can't weigh my (reinforced, narrowed and fourlinked) 8.8" at the moment but will gladly do so the next time it's out of the car. It would be useful to get some real figures up here to help stop the constant bitchfest that any valuable discussion on here becomes.

I have a narrowed 9 inch with full brackets , 35 spline MW axles , MW aluminum spool, MW disc brakes (which are just Wildwood) with a nodular center in my land speed camaro-- but its in the car . Probably a braced and four linked 9 inch (iron center) and a 8.8 in the same condition are pretty close.With an aluminum center and a titaniun spool of course the 9 inch gets lighter. For me , I like the quick swap of the 9 inch over the 8.8, quite frankly. You would need to go to a 35 spline axle to be as strong as the 9 incher so the weight might tip back the other way.
In my drag car where I have to change a ring and pinion between rounds on occasion (just change centers) that is a big deal but for a street guy its a different story. Maybe?

You already have yours cut and ready to go . Run that thing and see what happens. Everything has pros and cons . A twelve bolt chevrolet rear has less friction than the Ford in my Probe but I would never run it at the level of horsepower I have. The 9.5 Dewco is better than my 9 inch but the center section alone is 4 to 5k usd. We all make our choices.
George

 

[BB-Q]

Just as a side note doesn't anybody else find it odd how the measurement is always quoted as "31 splines" or "35 splines."
I checked my soooooper accurate very-nears and I only had a choice of English or metric, could find the button to convert diameters into "splines".

And like so much accepted--but never explored dogma, doesn't seem like anybody like to state what DIAMETER people are starting from and what they are wishing for in any of the 2 major measuring systems used in the world.
Is it that everybody knows how many mm or inches all the axles in discussion are already and I'm just too far behind the times?

Hmm.

Good job some of us take/took measurements. You want metric or footric for those 31 spline axles?

And an overall view if that helps: