Mechanics, I need help!! (F150 rear axle)

[wilkin250r]

My differential is shot. I know that I can't rebuild it myself, I don't have the tools or knowledge. And a shop is expensive.

But, replacing the entire rear axle is certainly within my capabilities, and from a junkyard, it's only about 1/3 the cost of having a shop rebuild my diff.


My question is compatability. My rear axle code is H9 (from the door jam), which is a limited slip 3.55 gearing. What kind of other axles will swap? Is there a certain axle code I'm looking for, or any basic rear end with the same axle type? Should I be looking for a code on the axle itself, rather than the door jam?

Other than the basic risk of any used parts, what other issues do I need to look for? Any tips, tricks?

I found an H9 axle, but the driveshaft mount is different, is this a deal-breaker or does it have an easy remedy?

From underneath, it looks like a few U-bolts, brakelines, shocks, and it's done. Is it really this simple, or am I missing something?

[Ghost-Rider]

Sorry to go kind of off topic.


But did you ever get a loud, humming noise ?

[416exfreak]

Other than making sure that you have all the proper hoses, clamps, bolts, nuts etc. you'll need to make sure its centered, make sure the spring pads are the same width.

Its not an overly difficult process. And neither is rebuilding a differential. Just google it, or look into an offroading website and ask for help from someone there.

[wilkin250r]

Originally posted by Ghost-Rider
But did you ever get a loud, humming noise ?

Yeah, sort of.

But my humming noise sounded like it was coming from the transmission, not the rear axle.

[416exfreak]

Originally posted by Ghost-Rider
Sorry to go kind of off topic.


But did you ever get a loud, humming noise ?

That either bearings or your low on gear oil.

We get that alot in our Samurai...its usually bearings or fluid...

[Ghost-Rider]

Originally posted by wilkin250r
Yeah, sort of.

But my humming noise sounded like it was coming from the transmission, not the rear axle.

Yea, mine makes a humming noise, I am getting my rear end rebuilt. I have a 97 F-150 with the limited slip.

I know the engine is good but if it's in a lower gear and i step on it and say the RPM's get around 4k and it shifts something kind of squeals, I figured that might be the trans. It's kind of hard to explain, But I know how to avoid that so I usually don't do it.

[Pappy]

wilkin, pulling the diff and installing or rebuilding it is gravy, much less labor then changing out the entire rear!

you can do it easily!!!

[07250ex]

pop of the case and see if u can identify any problems

[wvspeedfreak]

Wilkin,if the problem in the differential is just some bad bearings(most common) you would be farther ahead to just fix the rear you have.You can dissasemble the rear yourself with normal hand tools and just take the carrier and pinion to a shop to have the bearings pressed.If it is a problem with the actual ring and/or pinion gears and they need replaced then it gets a little more technical as you need to check and set pinion depth,backlash,etc.. which is done via shims.Given the knowledge you have I am sure you can do it.Differential work is pretty straight forward compared to most mechanical work on newer vehicles.

[wilkin250r]

Originally posted by Pappy
wilkin, pulling the diff and installing or rebuilding it is gravy, much less labor then changing out the entire rear!

you can do it easily!!!

When I say "differential", it's not just the diff. assembly itself, it's the entire axle assembly, including the ring/pinion and axle shafts.

I could do it, yes. But I don't want to, and I don't really have the tools.

I don't have an inch-lb torque wrench to measure the pinion bearing preload, I don't have a proper press to install the new bearings. Likewise, I have a 3/8 torque wrench capable of about 150 ft-lbs, easily enough for any motorcycle engine work. But I would need a much larger one, at least 1/2 inch and 250lbs, to install the pinion nut.

Now, I could buy a torque wrench, and any shop could press my bearings on, so that's not the only obstacle.

With as many metal shavings I'm seeing coming off the magnetic fill plug, I'm sure I need to either replace my ring/pinion set at $200, or my differential at twice that price. Heck, it might be both, running me about $600 in parts. Not to mention the TIME it takes to order those things.



If I can find a suitable axle at the El-Cheapo junkyard here in town, it will run me about $65, and add another $50 in misc. like brake pads and fluid change, and I'm up and running in two days.


Yeah, I'd like to go the proper route and rebuild it, but it's the off-season at work (so my funds are extremely low), and time is tight. With all these factors in mind, I'd rather just undo a few U-bolts, drop the axle, and slap a new one on. I'll keep the original and rebuild it when time and funds make it more convenient.

[Pappy]

are you sure its metal or is it clutch fibers from the clutch packs?

we used to rebuild these things at the track:p i would look into a rebuilt diff or even aftermarket.

and giving up a chance to actually buy a new tool:confused: you better hope noone from the heman wrenchhead guild see's this!

psst....gbcap runs a yard that has this type pf part..he may even be able to help you get a deal through his connections

[wilkin250r]

I never pass up the chance to buy tools. :devil:

The shavings can't possibly be clutch fibers. They're sticking to the fill plug, the fibers wouldn't stick because they aren't magnetic.

It's the slow season in the casinos, so money is tight. My wife needs the other vehicle for a road trip in a couple weeks, so TIME is tight.

I'm almost positive I need to replace my ring/pinion. I just can't see spending $300 on a gear set and installation kit, and fix it two weeks from now when it arrives, when I can spend $100 and have it fixed tomorrow.

[wilkin250r]

In fact, I'm SO stressed for time that I'm not even going to pop the cover off to actually see what the problem is.

If I pop it off, the new sealant requires 24hrs to cure, but I need the truck tommorrow morning to go pick up a new axle.

[Pappy]

LMAO!!!

i know the feeling, my diff cover is leaking and I need to pull it but ...excuses excuses:p i remember when a gasket and a tube of RVT was all that was needed:p

[Aceman]

Married? I think it's time you update your sig Wilkin, I know you've had that same one for years.:p

Unless you really do still have a girlfriend that rides your quad........in that case, good for you!:devil:

[wilkin250r]

Ok, we've touched on my married life, the wrenchhead guild, the my lack of tools, and even Pappy's differential woes.


But still, nobody has answered my original question!

There has to be a mechanic somewhere among out membership that knows a little about axle codes and swaps...

[Pappy]

Im pretty sure all the f150 (late models) use the same rear end. Your correct on the gearing. there is no axle code that i am aware of on the vin number or door jam sticker, just the gearing info.

as far as swapping in another rear, e150s should also be the same(check lug number), but you better get a tape measure out if your going to go salvage yard shopping. axle length, brake type (anti lock -non anti lock/disc/drum etc....youve never stated the year of your truck so that would be helpful. you are dealing with a 8.8 ford rear end with 31 spline axles if that helps:p

[400exrider707]

Originally posted by Pappy
Im pretty sure all the f150 (late models) use the same rear end. Your correct on the gearing. there is no axle code that i am aware of on the vin number or door jam sticker, just the gearing info.

as far as swapping in another rear, e150s should also be the same(check lug number), but you better get a tape measure out if your going to go salvage yard shopping. axle length, brake type (anti lock -non anti lock/disc/drum etc....youve never stated the year of your truck so that would be helpful. you are dealing with a 8.8 ford rear end with 31 spline axles if that helps:p

8.8 LS rear ends with 31 spline axles are also very common on explorers, but probably not the correct width, so I would definitley make sure you have the correct length axles. There are also 8.8 LS rear ends with 29 spline axles so watch out for those too. I would look for one from an f-150 or E-150 like suggested.

[NacsMXer]

On the late model F-150's, the ones with the 4.6 V8 have the 8.8 axle (round 10 bolt rear) and the ones with the 5.4 V8 have the 9.75 "sterling" axle (pear-shaped 12 bolt rear).
9.75"
http://www.offroadunlimited.com/ProductCart/PC/catalog/7086t.jpg
8.8"
http://www.offroadunlimited.com/ProductCart/PC/catalog/7064t.jpg


The axle code on the door jamb sticker specifies your gear ratio and whether or not it is LS as you may already know:

F-150:

19 – 3.55 Non-LS
18 – 3.08 Non-LS
H9 – 3.55 LS
B6 – 3.73 LS

[Scott-300ex]

You could put a Dana 44 under it.

If you get new axles in the rearend, make sure they are the right spline.

You sure its not just a u-joint makin noise? Like a clunking?

Pull off driveshaft, might leak oil, pull off u-bolts, brake lines, drop it, you might have to switch brakes with it.

Sorry in a rush might have forgot some things.

When you hook up, don't forget to bleed the breaks if you disconnect the lines.

Good luck.