Options for rear axle rebuild

[1998Exp]

At 150k (miles) or so, my rear diff developed the infamous whine under load, common to all Ford 8.8's. Shiny flakes in the oil showed that it's most likely a worn pinion gear. Since then I put over 20k more on it, and the whine isn't any worse, so the Ex will probably outlive me before the diff fails. Nevertheless the whine, even though not very loud, is quite annoying and I am considering my options:
a) Paying a drive train shop around $1000 to rebuild
b) Buying a reman axle, like the Zumbrota. Again, around $1000.
c) Spending around $750 on parts and tools (other than an indicator, I don't have any of the specialized tools needed), and rebuilding it myself. With zero experience on this tricky job, I am fully expecting to do it twice - at least.
I am not considering the option of installing a rear end from a junk yard - it's probably not going to be any better than what I have now - if not worse.

Would love to hear from those that repaired their whiny diff! Thanks in advance!!

 

[410Fortune]

$1000 is a bit too much
First off what axle is this? I mean I know its 31 spline 8.8....what gears do you have and is it a limited slip?
I will assume the $1000 included all new parts?

 

[shucker1]

$1000 for a shop rebuild does seem high.

If you go Re-manufactured you have to add in shipping for both directions.

If you rebuild yourself its not hard to do but does require some special tools and can be very tedious to get it right the first time.

 

[koda2000]

With the tools needed (and the required knowledge & skills) it's not that hard to rebuild your own. The knowledge & skills are the key to the success.

 

[bats]

If you're just doing a straight rebuild and not a re-gear you can probably do half the work yourself. (Gurus correct me if I'm wrong here.) The only part that really requires special knowledge and tools is setting up the gears. The axle shafts and brake hardware is wax off wax on.

 

[gmanpaint]

$1000 sounds about right for a shop that offers a good warranty. To cover this warranty, they will provide the parts. Shops around here (worthy) charge $600 to open a diff, and remove a carrier. $400 for Gears, master rebuild kit, axle bearings, seals, & if an LS, the clutch kit & fluids.

If I supply all those parts, its going to cost me that $400 easy. I can shop and find some local home shop mechanics to do it for around 500, but I get no warranties with anything, other then free labor to rebuild what breaks, and buy the parts again.

Your area might be different, as I am sure it differs all over, but the bottom line is, you want it done right, and with a blanket warranty.

 

[1998Exp]

$1000 is a bit too much
First off what axle is this? I mean I know its 31 spline 8.8....what gears do you have and is it a limited slip?
I will assume the $1000 included all new parts?

It's a 3.73 (does that matter?), limited slip.
It's been a while since I got that $1000 estimate, and they were not specific on which parts they would replace for that money. I remember asking what brand of gears they use, and was told "a good one," which did not instill much confidence in that outlet. From my (very, very limited) experience with auto repair businesses, most of them don't shy from making an extra $20 by using cheap parts...

 

[donalds]

$1000 not to bad if you include all the parts and labor

My axle had the infamous whine
In order to replace all the bearings
The pinion gear must be removed
Then to reinstall everything
Not to hard but you will need some tools

When mine was bad whining it was the axle bearings and carrier bearings
Here is a thread you may want to read and watch the vids Experts, I need some help.. (Rear axle assembly)

 

[koda2000]

$1000 sounds about right to me for a full rebuild on an LSD (quality parts, labor w/warranty).

 

[donalds]

$1000 sounds about right to me for a full rebuild on an LSD (quality parts, labor w/warranty).

I guess if it has a warranty
I think I'm just used to being broke and have to do everything my self lol

 

[410Fortune]

Well does the $1000 include a new ring and pinion?
Does it include a rebuild of the limited slip?
Or does it simply include new bearings and seals along with a new pinion bearing, seal and crush collar plus fluid. I mean $1000 can be spent alot of different ways.
$1000 is a decent price if they are using a new ring and pinion (Not Motiv gear!! Use precision, Ford, Yukon, etc, no Italian metal for me) rebuilding the limited slip with new clutches, replacing all seals and bearings, new E brake shoes and new brake pads/service the rear calipers along with new synthetic fluid and friction modifier. Thats $1000 worth of parts and work.
Just know what you are getting for your $$$$, I am guessing that's why you started this thread?

$1000 is a good price IF they are doing all of that. $1000 is a rip off for just a master install kit and fluid........without replacing any gears or rebuilding the LS

I am 3.5 hours from Seattle and I have a 100K axle from a 1999, 3.73 limited slip, has all new brakes I am selling it for $300.... another option to consider is the used market.....

 

[1998Exp]

Many thanks to all who responded!
The shop that gave me the $1000 estimate moved to a different location, almost 100 miles away, so probably not an option.
Since winter is coming and there will be no gardening for a while, I am considering the DIY option and pricing parts. Finding that Yukon is horrendously expensive, and it will probably take $1000 just in their parts for a complete rebuild. Motive is the cheapest, but 410Fortune is against it, so I am thinking of Ford instead. The Ring and Pinion gears will certainly have to go, along with all the bearings. Probably won't know if the carrier needs to go (along with its gears) before I take things apart. And how about the limited slip clutches? I am planning on measuring the release torque before taking things apart. But if it's within spec, is there a way to tell by visual inspection how much life is left in them?

 

[Brian Middleton]

If it makes it all the time it's probably the diff bearings. I did my own rear end and had a shop do the front axle and it was $590 for labor alone (with me removing the entire axle and taking it to them) and it was awful trying to find the shims for the front... It's not uncommon for the bearings to whine from poor maintenance. The upside is you can drive it a long time regardless if it's the bearings or the ring and pinion. I'm an open book on this if you have questions.

 

[1998Exp]

If it makes it all the time it's probably the diff bearings. I did my own rear end and had a shop do the front axle and it was $590 for labor alone (with me removing the entire axle and taking it to them) and it was awful trying to find the shims for the front... It's not uncommon for the bearings to whine from poor maintenance. The upside is you can drive it a long time regardless if it's the bearings or the ring and pinion. I'm an open book on this if you have questions.

Thanks for your offer to assist! I will certainly use it once I get into the thick of things.
As for the details, it whines only under load - which, in my (very inexperienced) opinion, is a sign of ring and pinion gears or pinion bearings. Also, when I changed the oil a couple years ago, there were shiny flakes in it: a sign of worn gears I assume - but what do I know? And yes, I already put about 20,000 miles on it in this condition, and it doesn't seem to be getting any worse. I drive this vehicle very little these days, mostly when I need to haul my trailer, but that whining sound is driving me nuts each time I do...
Out of curiosity, which parts did you end up replacing in the rear axle assembly, and what brand(s) you used? Did you do on the vehicle, or removed the entire axle?

 

[shucker1]

Pop the rear cover off and send us a good picture of the gear mesh pattern and the oil that comes out.

You can let the used oil sit in a container for a few days then run a small magnet though the bottom to see what it picks up.

10 to 1 you are going to find some very heavy shiny spots on the "Heel" (Outer Most Side) of the ring gear.

This is caused by the pinion bearing going bad and the pinion thrusting forward away from the ring gear under load.

Any chips or chatter marks on the ring gear pretty much means it's toast.

If none are found then you are hunting a pinion or carrier bearing.

A good pattern should run right in the middle of the ring gear.

Did you do on the vehicle, or removed the entire axle?

It's a lot easier with the axle out. You have room to clean everything really well.

If the carrier and housing were bad (Cracked, Etc) you would know it. That's usually a catastrophic failure.

 

[gmanpaint]

Noise under load, is normally a carrier bearing.

I have gone through that twice on 2 rigs now.

 

[Brian Middleton]

Thanks for your offer to assist! I will certainly use it once I get into the thick of things.
As for the details, it whines only under load - which, in my (very inexperienced) opinion, is a sign of ring and pinion gears or pinion bearings. Also, when I changed the oil a couple years ago, there were shiny flakes in it: a sign of worn gears I assume - but what do I know? And yes, I already put about 20,000 miles on it in this condition, and it doesn't seem to be getting any worse. I drive this vehicle very little these days, mostly when I need to haul my trailer, but that whining sound is driving me nuts each time I do...
Out of curiosity, which parts did you end up replacing in the rear axle assembly, and what brand(s) you used? Did you do on the vehicle, or removed the entire axle?

I got the Pinion and Ring gear from eBay and the ONLY reason I replaced them was because I chipped a tooth on the pinion gear trying to remove the bearing. I got a bearing kit from my local auto parts store and took it to a local shop that removed the old bearings and pressed the new ones back on.

On easy thing to check is for play on the pinion by putting the axle on jack stands and seeing if you can move the pinion yoke by hand. It should not have any movement at all.

I did not remove the rear axle I left it in but I had to on the front.

Also, I get a crush sleeve elimination kit with a solid spacer that I used on the back. Other helpful things: put sealant around the pinion seal and use an HD one if you can find it and use sealant on the differential cover even if you have a quality gasket.

 

[1998Exp]

Thanks again for all your suggestions! Oddly, the whining from the rear diff has stopped. I know that it's not good news -- something probably wore down further.
But here is the funny part: the whining under load has now moved to the front diff! This seems to be a lot less common than the infamous 8.8 whine. I know nothing about these Dana things. Anyone with experience?

 

[Brian Middleton]

Thanks again for all your suggestions! Oddly, the whining from the rear diff has stopped. I know that it's not good news -- something probably wore down further.
But here is the funny part: the whining under load has now moved to the front diff! This seems to be a lot less common than the infamous 8.8 whine. I know nothing about these Dana things. Anyone with experience?

I'm not sure how the noise from the rear diff would stop... I would check the fluid in it before doing anything. The front diff is a bit strange. I would take the front drive shaft/prop off and check for play going into the housing.

 

[imp]

Thanks again for all your suggestions! Oddly, the whining from the rear diff has stopped. I know that it's not good news -- something probably wore down further.
But here is the funny part: the whining under load has now moved to the front diff! This seems to be a lot less common than the infamous 8.8 whine. I know nothing about these Dana things. Anyone with experience?

@1998Exp
There is a considerable difference between the sound made by bad pinion bearings, if it occurs before gear damage has begun, and gear-tooth pattern discrepancy, because the pinion turns almost 4 times as fast as the diff. carrier and ring gear. Much higher pitched whine at say, 20-40 mph. Damaged gear teeth howl like hell. Bets are good your noise stemmed from normal gear and bearing wear, was coming right from the gear teeth, and more than likely the ring gear teeth only; pinion gear teeth have huge contact areas rolling in comparison to the ring gear teeth. Especially since it occurred only while loaded, and not in "coast"

Diff. bearings going bad grumble, no whine, because the rollers are turning much slower than the inner race or the pinion bearings. Once they get REAL bad, gear tooth pattern reaches misalignment enough to howl like hell. Just as @shucker1 said. imp