Will this axle work?
 

I'm just making sure I got the right one here, it's supposed to be out of an explorer rear end that will fit a 99, but I want a positive identification of what it is before I start working on it. The axle tag states:

S621A
3L73 88 8609

Can anybody read this and tell me what it's out of? One axle tube measures approx. 17 inch, other measures approx 20 inch. Overall length is approx 4'6.

Pictures:
Attachment 206548
Attachment 206549

it looks like a 8.8 with 3.73 gears and a limited slip. Dont know about the rest.

Holy crap, I didn't even think about that. 3L73 IS a limited slip! Hahah, perfect.

Make sure you're front gears are 3.73s as well before you try to use 4x4 with the new axle. Also depending on how many miles the axle has on it the LS unit might need to be rebuilt so it won't act like an open diff.

I believe that one's out a 5.0L because it has the factory traction bars on top. You realize that it is not a direct replacement for a Ranger axle, right? Spring over vs spring under, relocating perches and shock mounts and all that.

the factory traction bars wont work on a SOA will they:shrug:

i didn't think the 5.0's came with 3.73 gears? i though they all had 3.55 gears?

I don't see how they could without major mods. IMO, it would be far easier to just use something like the Duffs.



I don't have any info on that. Maybe a towing package or optional tire size or AWD forced the ratio change. I'm pretty sure that the traction bars were V8 only, though.

Yeah, the traction bars were V8 only, but the rear end is getting cracked open, LSD is being rebuilt with 8 clutch packs, I'm going to shove some new 4.10s in the back and I'm aware that I do need to weld on new spring perches. I'm trying to find some anti-wrap perches that I can toss on there and a whole new hardware kit so I can have everything fresh when I bolt it up.

But yeah, I realized this wouldn't be a quick bolt up, that it would require some work. If I get away with getting this done for around $800 (Rebuilt rear, new gears, rebuilt LSD, Spring Perches, Powdercoat, new rear brakes and calipers) I'll be happy. I'm probably going to end up doing a full writeup on it for anybody else in the future.

I would have stayed with my ranger axle, but I plan on using this truck to tow with. I know the engine can handle it, now I know the rear end will, my only concern from here on will be taking it easy on my tranny.

Also, what are you talking about when you mentioned Duffs?

James Duff traction bars.....

there is already a write up on here about swapping in an Explorer axle...

Gotcha, and I searched for a decent writeup and can't find one that's really helpful, unless I'm missing it somehow.

look in the How-To section......it was written by ScottG...

Cool, thanks. Also, would anybody know if they sell a whole leaf spring perch kit. I'm looking for the perches, the U bolts and everything that comes with them.

Also, are my axle tubes the same diameter as a Dana 60s?

check out http://www.mountainoffroad.com/more.htm and look in their catalog under "axle mounting hardware" for the ford 8.8 install kit. I don't remember if you want part number 98500 or 98600 (different leaf spring widths) but I believe it is 98600, the kit for the XJ. these come with MASSIVE spring perches and shock mounts, u-bolts and u-bolt plates.

I was looking at those earlier but didn't know if that kit would work. I'll give them a call up in the morning and see which one uses the 2.5 inch leaf.

Thanks!

Wow, I just wanna say, what a bunch of crap people have been loading me up with so far. It initially sounded like all I had to do was reweld the perches to the top of the axle. Looking at it further, if I want a sway bar, I need to make or modify my own end links or mounts for those, if I want shocks, I've got to make my own mounts for those on the axle because the explorer ones are both mounted in the back, and are attached to the leaf springs. Come to find out, this axle really IS a little longer than my stock axle.

Seriously, how many people have actually gone all the way through with this? I'm going to finish what I've started, but I will never recommend nor do this again. What a bunch of crap information I've gotten from this board so far. Don't get me wrong, some of you have been helpful, but it would have been nice to have gotten information from somebody who has done this/knows what they're talking about.

By the way, the how-to writeup is junk.

He told you multiple things you had to do right there. Maybe you should do some research before you start a project so you know what your getting yourself into and if you don't want help don't start a thread, that is all
:439:

I apologize for that, I misread that part and when I came to it today, it was a little bit of a surprise. For some reason, I only read the spring perches.

But how do people remedy this situation is my concern as of now.

Edit : I still stand by saying the "how-to" is junk.

um, all you had to do was asking more questions and someone would have answered them!


The axle is 1.5inchs wider (.75 on each side)
Spring Perches need to be welded on if you want a stock ranger setup
Either Shock tabs are needed, or you could use 2 stock passenger side explorer spring plates


If you looked at the how-to, it was on a lowered truck, so spring perches were not needed, but theres a link on the howto to a discussion about it.


If you need more help, let us know

ScottG

oh, and if you want to keep saying the howto from 2 years ago is junk, feel free to make your own for us to post up

Already 3 steps ahead of you on that one. Thanks for the info btw.

Another question. Is there any reason to weld new shock mounts onto the axle? Any real benefit from that vs the explorers spring plates? Just a quick thought but it seems to me you risk bottoming out the shock easier with the spring plates seeing as I believe they would be mounted up considerably higher.

Am I correct in this assumption?

I agree. The stock shocks would not last very long mounted to the Ex plates on top of the springs.

To use the Ex plate mounts, you would need to run shocks that have a compressed length that considerably shorter than stock- I would guess 6" shorter, possible more. That means that the extended shock length would be shorter than stock by roughly double that amount. This would severely limit wheel travel and could damage the shocks from frequent topping.

Also, the Ex shocks are both behind the axle and the Ranger shocks are staggered. So you'd need to either rearrange the Ex plates for a staggered setup or move one of the upper Ranger mounts.

It seems to me that adding Ranger-style shock mounts to the Explorer axle would be the most straightforward method.