axle swap questions

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T.Low
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axle swap questions

Post by T.Low » Fri Feb 27, 2009 2:39 am

Let me preface this post by saying I don't pretend to be all that knowledgable about axles. (OK, maybe to the average joe on the street I pretend to be :D , but not to you guys!)

And here's my situation:

I want my front up a little more (2 more inches maybe?) , but mainly I really don't want to worry about breaking a front axle up in the mountains 100 miles from no where.

I also want to add an ARB style bumper with winch and don't want the front ot sag any lower than it already is.

I have already upgraded my stock rear axle with 4:10 gears (front axle as well of course) and an Eaton positraction unit. I have already bought the wheels and tires that I want.

I have the front body lift installed with the stock torsion keys. I am very leary to raise the front end using the new lift keys as I am convinced that it will make for a weak front end out on the trail. Whats the point of turning my van into a great athlete if it has weak knees?

I guess i am looking for the shortest route to a stragiht axle swap, meaning not having to swap a rear axle.

And with a straight axle, I think I want to go with coil springs.

Please feal free to question my logic and assumptions at any point of this post, including up to this point.



Solution Option 1: I have found a Dana 44 Low pinion out of a '76 F250 with an ARB Airlocker.

BUT of course its an 8 lug bolt pattern vs my rear which is a 6 bolt ('03).

REMEDY: Seller says he will give me this Chevy 1/2 ton Dana axle for free if i buy the Ford ARB axle. That way I can swap axle shafts and it will still fit my current wheels. That way, of course, i can keep my current rear axle. (He bought a Chevy 1/2 ton and got all the parts of it that he needs, has way too much truck stuff around the yard and the Chev is going to the recycler including both front and rear Dana 44 3.09s if he doesnt' sell them on CL soon. )

Is this true? Will they swap out like that?

When asked, he replied that its a 4:10, then back peddled and said "well, you know, 4.09". I said no, I don't know, what do mean? He said front axles are a little different than rears, as in the fact that they are actually 4.09 or 4.095...blah blah blah transfercase blah blah blah." He lost me. IS THIS TRUE? I have never heard that before?

He also has the following axles sitting around his place: Would I be better off with one of these?


1 - 1976 F250 Dana 44 drivers side low pinion with ARB AIR LOCKER, 4:09 gear lifetime warn hubs, axel truss and very low mileage parts such as bearings. (this is the one I'm refferring to above).

2. 2 Hi pinion Dana 44's one out of a 74 Bronco and the other out of a 77 F150 Both are coil suspension front end styles. I am not sure of the gears in them but I should know by Sunday eve.
3. I also have many different trannys, tranfercases and multiple dana 60 and corp 14 bolt rearends.

4. I have some used gear sets and toyata parts as well.

Let me know what you want. I might just have it.




Dean, in your SAS thread you list the Ford axle at 68", and the Astro is conventionally thought to be 66". How much difference would the resulting one inch wider in the front make for the handling of the van? Aren't Fords wider in the front anyway?


Like I said, he told me he would give me the two Chevy Dana's (12 bolt corporates) if I bought the Ford with the ARB Locker, so i'm thinking that if all this parts swapping works out in the front, i also have a rear axle to do the same thing in the rear if i ever need to. Sensible or not?

Any and all info and/or smart ass comments will be helpful!

Thanks guys.

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Re: axle swap questions

Post by Someone » Fri Feb 27, 2009 4:35 am

you can get a set of spacers/bolt pattern converters for the rear. They are machined aluminum and come in all different widths... I Run 1 1/2" spacers on the front of my toyota and have had no problems whatsoever, you should be able to get them to convert to 8 bolt.

1/2 ton axles will only be 5(2wd) or 6(4wd) bolt, you need to get into a 3/4 ton for 8 bolts.... the shafts will not fit anyways as the astro has an offset rear diff...

My opinion would be to pick what you want for the front and try the spacers in the rear... you can always throw a dana 60 or some sort of full floater under there later.
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Re: axle swap questions

Post by dilly » Fri Feb 27, 2009 4:55 am

if you're thinking coil springs anyways i'd get one of the high pinion 44 (asuming the gears are the same) then you could use the ford radius arms, not the best suspension but asuming the coil buckets can be adapted to the sub frame (try measuring where the coilspring would end up) it would be fairly easy. also the high pinion is stronger . about the chevy axles, are they dana 44s or corporate 10bolts? i'm not sure if the knucles are the same on the 10bolts but the 44s will interchange. one more thing, i'm thinking you'll need more than 2" more lift just for differential/oilpan clearance.
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Re: axle swap questions

Post by T.Low » Fri Feb 27, 2009 5:02 am

dilly wrote:if you're thinking coil springs anyways i'd get one of the high pinion 44 (asuming the gears are the same) then you could use the ford radius arms, not the best suspension but asuming the coil buckets can be adapted to the sub frame (try measuring where the coilspring would end up) it would be fairly easy. also the high pinion is stronger . about the chevy axles, are they dana 44s or corporate 10bolts? i'm not sure if the knucles are the same on the 10bolts but the 44s will interchange.

He says they are Dana 44 corporate 12 bolts.

http://bellingham.craigslist.org/pts/1051803093.html
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Re: axle swap questions

Post by LiftedAWDAstro » Fri Feb 27, 2009 12:30 pm

Ok, here is what I would do if I was going to do it again...and I probably will at some point. :D The front WILL be coil sprung with a custom 3, 4 or 5 link setup.

I would look seriously at some new 2003+ Dodge ram 2500 or 3500 axles. You can get them in 3.73, 4.10 or 4.56 (Powerwagon). Yes, you will pay more for a newer set of axles but, you'll get ABS, front AND rear discs, high pinion front diff, no front axle disconnect and you probably won't need to do any rebuilds! The only problem with them is that you are limited on locker choices. The rear can come with a very stout posi which is very similar to a Detroit TrueTrac. The front can be retro-fitted with any locker that fits the GM 9.25" IFS front diff. I think you are limited to the lock-right. You can purchase the Eaton E-lockers used in the Powerwagons for both the 9.25" front and 10.5" rear axle. The front axle is setup for coils and 5 link and the rear is setup for leafs.

The next option using the parts you are looking at and keeping your stock (weak :yawinkle: )rear axle is to use the LPD44 from the F250 and using the outers from the GM D44. I think the axle "C's" are the same such that you can disconnect the outer rotors, calipers, hub and bearings, spindle and knuckle from the Ford D44 and the GM D44 and swap them out. This will give you the front as the standard GM 6 x 5.5" bolt pattern. I am not 100% sure this will even work but if you go tp http://www.Pirate4x4.com and start reading you will find the answer there. Expect to spend weeks reading all the technical threads there!!!

The 4.09 thing...He is right, they used 4.09 fronts and 4.10 or 4.11 rears. That is very normal.

Skip both of those 1/2 ton HPD44's as the axle tubes are weaker and the radius arm wedges may be cast in and you can not remove them. If you are going with the radius arm setup then the high pinion out of the 77 F150 would be better.

My feeling is if you are going to the trouble to do the front SAS, you really ought to swap to a much stronger rear axle as well.
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Re: axle swap questions

Post by T.Low » Fri Feb 27, 2009 7:53 pm

Excellent weekend reading, thank you, thank you, thank you. :cheers:

And thanks for the PhD thesis Dean. Some great advice there.
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Re: axle swap questions

Post by gabequest » Sun Sep 13, 2009 3:53 am

TLow:
I hear you on the weak knee issue; surely our weakest link!. I've got the fabbed torsion keys and my lift is where I want it...but, when wheeling,with suspension maxed out on terrain, I am concerned about breakage. I ground something down in my passenger CV joint: a mystery chunk of welded metal and the bearing pins fell out everywhere. It would be cool if someone made HD slip-yoke axle shafts and mega travel ball joints like Downey does for toyota's to accommodate the travel.

ps. Still have pop-top envy. Just spent a week in the van at Burning Man and really could have used the space. Sleep upstairs, cook and chill downstairs. Can you slide the bed back and stand up to cook (like with my stove set-up)?
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Re: axle swap questions

Post by T.Low » Sun Sep 13, 2009 4:07 am

Affirmative, GQ.

And thanks.

And way to represent at Burning Man. Did you get the stink eye from any VWs?

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And I must say, I've noticed that buying the dual sport and wheelieing the hell out of it for hours on end keeps me from pushing the van to/beyond its limits. Thats part of my justification for the bike and I'm sticking to it. :yawinkle:
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Re: axle swap questions

Post by Smiliesafari » Sun Sep 13, 2009 1:54 pm

On the subject of gear ratios.........Some gear mfgs round up the numbers and some round down. Count the number of teeth on the ring gear, divide that number by the number of teeth on the pinion and that will give you the ratio.
Example: 43 teeth on the ring gear, divided by 14 teeth on the pinion = 3.3076923. Some mfgrs call that a 3:30 and others will call that a 3:31. As long as both differentials have the same count on the ring and pinion then you're good to go. \:D/
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Re: axle swap questions

Post by gabequest » Sun Sep 13, 2009 4:27 pm

"GQ", I like that...find me a magazine cover!

I can't really tell if I get the stink eye from the VW's because I most of the time I blow past them on the road. I will say that many of the drivers give me the "thats cool nod". At this point, I bet they are so tired of arriving late to party that they have van envy.

TLow, if your not gonna really push your van, go with the keys (if Dan still sells em'). Again, I have pushed my van, and for the most part it holds up.
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Re: axle swap questions

Post by T.Low » Sun Sep 13, 2009 4:46 pm

gabequest wrote:"GQ", I like that...find me a magazine cover!

I can't really tell if I get the stink eye from the VW's because I most of the time I blow past them on the road. I will say that many of the drivers give me the "thats cool nod". At this point, I bet they are so tired of arriving late to party that they have van envy.

TLow, if your not gonna really push your van, go with the keys (if Dan still sells em'). Again, I have pushed my van, and for the most part it holds up.

Ha, thats great about the VWs.

I hear what your saying, but I know myself...I will always find the occassion to push the van and most times it will be far away from civilization...the keys have been sitting patiently in my tool box as they came with my lift kit order back in Feb '08 (Put me in, coach! :tonqe: ) Not to discount your feed back at all, its just that knowing what I know, and with the feed back from Dean, lockdoc, my brother inlaw and others, I just can't get myself to go that route. Keep pushing it an continue to give us reports on the reliability and strength.
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Re: axle swap questions

Post by gabequest » Tue Sep 15, 2009 1:00 am

Ummm....I can't afford to keep pushing it in case something breaks :rolleyes:
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