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rear diff ?

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Old Jun 30, 2006 | 09:47 PM
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rear diff ?

My diff tag reads something like this
4:30 ****** **
***** ** LS
The 4:30 is gear ratio......does LS mean limited slip?
I have a leaking diff and I'm going to fix this weekend.
Can I pull the yoke and replace the seal?
Is a after market diff cover less likely to leak?
Thanks in advance
 
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Old Jun 30, 2006 | 10:15 PM
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yes and yes
 
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Old Jun 30, 2006 | 11:17 PM
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Hmmm... usually Ford diff tags say "4L30" for a 4.30 limited-slip. And "4 30" for a open diff 4.30.

What's the axle code on the door sticker? That'll tell you ...
 
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Old Jul 1, 2006 | 08:31 AM
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Originally Posted by krewat
Hmmm... usually Ford diff tags say "4L30" for a 4.30 limited-slip. And "4 30" for a open diff 4.30.

What's the axle code on the door sticker? That'll tell you ...
Door sticker has been gone for years.
Once i take the cover off all will be revealed I guess
 
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Old Jul 1, 2006 | 08:34 AM
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Originally Posted by Stoner
yes and yes
I asked 3 questions so..........
 
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Old Jul 1, 2006 | 08:45 AM
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You talk of pulling the yoke and replacing the seal, but then ask if an aftermarket diff cover will not be as likely to leak. Where is the leak coming from now? If its from the yoke area, then there is no need to pull the diff cover (other than to be 100% sure of the ratio) Yes, you can pull the yoke off, replace the seal, and reinstall the yoke. If its leaking from the diff cover area, then yes there are 2 other options for diff covers, however there is no reason that your factory diff cover should be leaking. Take it off, clean it up and put it back on with some good silicone sealant. The 2 companies that sell good aftermarket diff covers are Mag Hytec and PML.
 
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Old Jul 1, 2006 | 11:06 AM
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Originally Posted by Texascadillac42
You talk of pulling the yoke and replacing the seal, but then ask if an aftermarket diff cover will not be as likely to leak. Where is the leak coming from now? If its from the yoke area, then there is no need to pull the diff cover (other than to be 100% sure of the ratio) Yes, you can pull the yoke off, replace the seal, and reinstall the yoke. If its leaking from the diff cover area, then yes there are 2 other options for diff covers, however there is no reason that your factory diff cover should be leaking. Take it off, clean it up and put it back on with some good silicone sealant. The 2 companies that sell good aftermarket diff covers are Mag Hytec and PML.
It appears to from the cover but, as I will be under it, I will replace the seal and do all the universal joints etc.
Thanks guys
 
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Old Jul 1, 2006 | 01:20 PM
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I wouldn't touch the seal if it's not leaking. The new one might leak.

Eric
 
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Old Jul 1, 2006 | 09:44 PM
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Originally Posted by desrcr
I asked 3 questions so..........
lol..that's what I get for rushing and not reading the whole post
 
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Old Jul 1, 2006 | 09:53 PM
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I 2nd that

If the Pinnon seal not leaking dont mess with it it's called pinnon bearing preload if you change it you mite open a can of worms some of use are dealing with pinnon problems now trust me you dont want this headace.

Originally Posted by etcetera
I wouldn't touch the seal if it's not leaking. The new one might leak.

Eric
 
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Old Jul 1, 2006 | 10:10 PM
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Yeah, if the pinion seal isn't leaking, don't mess with it.

Check the breather for the diff, on 4x4's it's a hose that goes up to the chassis. If it's blocked, as the diff heats up, it pushes gear lube out whereever it can. Pinion seal, cover, etc.

But I think once the cover is leaking, you really need to re-glue it anyway. Check the breather.
 
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Old Jul 2, 2006 | 10:55 AM
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Originally Posted by krewat
Yeah, if the pinion seal isn't leaking, don't mess with it.

Check the breather for the diff, on 4x4's it's a hose that goes up to the chassis. If it's blocked, as the diff heats up, it pushes gear lube out whereever it can. Pinion seal, cover, etc.

But I think once the cover is leaking, you really need to re-glue it anyway. Check the breather.
Its weeping so................
Are y'all scared to maintain your stuff?
Follow directions, use the proper tools and consult experts (you guys are helpful but far from experts) for their input.
I would rather work on it on my terms, then try to find a qualified mechanic out on the road.
 
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Old Jul 2, 2006 | 11:55 AM
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Originally Posted by desrcr
Its weeping so................
Are y'all scared to maintain your stuff?
Follow directions, use the proper tools and consult experts (you guys are helpful but far from experts) for their input.
I would rather work on it on my terms, then try to find a qualified mechanic out on the road.
Uh, I might not be an "expert" but I know when setting up pinion preload is beyond a certain level of backyard mechanic.

If it's a Sterling 10.5", setting the pinion preload has to be done with the diff carrier out, a new crush sleeve, and a new nut (or locktite the old one if you're cheap).

If it's a Dana 60/80/44, the preload is set with shims, so removing the yoke, replacing the seal, and re-torquing the nut to specs is doable.

But if it's the Ford/Sterling unit, removing the yoke and just replacing the seal and re-torquing the nut WILL give problems. You can't just take off the yoke and replace the seal. You have to gut the entire thing and setup the pinion preload CORRECTLY.

Side note: Even if the seal is "weeping", CHECK THE BREATHER.

art k.

ps: I've rebuilt quite a few rear-ends (and front-ends) and never had one fail. Because I did it the RIGHT WAY.
 
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Old Jul 2, 2006 | 12:44 PM
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Art ,I've done quite a few myself also.
You don't need to remove the carrier unless putting all new bearings in.
What needs to be done is to determine why the leak first.(breather,worn pinon bearings or carrier bearings) If you feel its just the seal and not bearings you can just measure what the preload is with wheels off and no brake drag.using a dial torque wrench while rotating the flange nut before removing it.
Then remove flange nut replace the seal and torque the flange nut down to get your recorded preload .your done .It helps to have a special flange holder though and a very acurate dial torque wrench.

I only have done them this way for yrs ,never had a comeback yet.
But 9 times out of 10 the cause of a seal failure is worn bearings on the pinion or carrier .
This causes laterial movement which takes out the seal.
So when you see a seal leak its usually something deeper inside that is the cause .
My $2 cents
Rich
 
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Old Jul 2, 2006 | 12:50 PM
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do as the guys tell you the only reason isee a stock cover leak is when some one rushes and dosn't make sure both surfaces are dry of oil. don't and they leak, make sure the vent hose is clear and the pinion seal you can do it but as art just stated it's not really a back yard job and the axles ans diff should be out so you can proiperly crush and preload a NEW crush collor .
soory i i seem a tad ruff but i do about 5 sets a week and now all to well what needs to be done correctly.
also 90% of the time when a pinion seal leaks it due to a bad bearing.
 
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