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Replacement Front Diff Fill Bolt

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Old Mar 10, 2023 | 11:01 AM
  #1  
Gavin Costigan's Avatar
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Default Replacement Front Diff Fill Bolt

My front diff is leaking slightly and well overdue for a fluid change. I recently rounded the fill bolt trying to get it off. Does anyone know the size/thread pattern so I can source a new bolt? I cant find one anywhere and am hoping I can maybe pick a similar one up at a hardware store and throw a crush washer on it.

Also strategies to remove this almost completely rounded bold would be appreciated.
 
Old Mar 10, 2023 | 03:16 PM
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Cant help with the rest, but these bolts should only be tightened to a few foot lb. How did you ever strip it? Hope you are not one of those guys still using 12 point sockets.

It’s anticlockwise to loosen it LOL! Unless you are laying underneath upside down

Use a 6 point socket (get a set of the type that have cutouts on the points so that they do not round off anything) or

You can get a special socket bolt extractor tool. The socket has teeth that bite into the bolt, or

If that is too difficult, cut a slot in the bolt head with a Dremel, and spin off with a flat blade screwdriver or tiny pry bar.

Add heat and Kroil as required.
 

Last edited by finall; Mar 10, 2023 at 03:21 PM.
Old Mar 10, 2023 | 05:28 PM
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Originally Posted by finall
Cant help with the rest, but these bolts should only be tightened to a few foot lb. How did you ever strip it? Hope you are not one of those guys still using 12 point sockets.

It’s anticlockwise to loosen it LOL! Unless you are laying underneath upside down

Use a 6 point socket (get a set of the type that have cutouts on the points so that they do not round off anything) or

You can get a special socket bolt extractor tool. The socket has teeth that bite into the bolt, or

If that is too difficult, cut a slot in the bolt head with a Dremel, and spin off with a flat blade screwdriver or tiny pry bar.

Add heat and Kroil as required.
The dummys at the dealer probably did it when they did the seals on it. And when they tightened my oil filter with a 24ft long breaker bar and an excavator.
 

Last edited by Gavin Costigan; Mar 16, 2023 at 09:44 PM.
Old Mar 10, 2023 | 06:03 PM
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Front Diff
Use a 15mm socket to remove the fill plug and a 13mm socket to remove the drain plug.

After your diff is completely drained, replace the drain plug and tighten to 24 lb-ft.
Fill the diff until fluid is level with the fill hole. Be sure it's not pour back from the bottle and the diff is really full - this can be achieved by using a rag to wipe inside the hole - if after removing the rag, fluid continues to drain out of the fill hole you are full. Insert the plug and tighten to 24 lb-ft.

The manual calls for synthetic fluid only - 75W90. The manual states it requires 2.6 pints of fluid, but fill it until it is full.



 
Old Mar 11, 2023 | 10:29 AM
  #5  
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Default H2 Front Differential Case Cracked Off

Originally Posted by finall
Cant help with the rest, but these bolts should only be tightened to a few foot lb. How did you ever strip it? Hope you are not one of those guys still using 12 point sockets.

It’s anticlockwise to loosen it LOL! Unless you are laying underneath upside down

Use a 6 point socket (get a set of the type that have cutouts on the points so that they do not round off anything) or

You can get a special socket bolt extractor tool. The socket has teeth that bite into the bolt, or

If that is too difficult, cut a slot in the bolt head with a Dremel, and spin off with a flat blade screwdriver or tiny pry bar.

Add heat and Kroil as required.

‘’Question:

Has anyone experienced their Front Differential Casing Cracking off. Mine has cracked in half like a Coconut Shell. Is there a way to replace just the casing or will I have to replace the entire Front Differential? Is this a Recall issue???
 
Old Mar 11, 2023 | 01:54 PM
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15588374
PLUG, FRONT DIFFERENTIAL CARRIER OIL>> DRAIN(M12X1.5)(5.400)

8672354
PLUG, FRONT DIFFERENTIAL CARRIER OIL>> FILLER(M20X1.5)(4.105)
 
Old Mar 12, 2023 | 12:07 AM
  #7  
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Originally Posted by hummerz
Front Diff
Use a 15mm socket to remove the fill plug and a 13mm socket to remove the drain plug.

After your diff is completely drained, replace the drain plug and tighten to 24 lb-ft.
Fill the diff until fluid is level with the fill hole. Be sure it's not pour back from the bottle and the diff is really full - this can be achieved by using a rag to wipe inside the hole - if after removing the rag, fluid continues to drain out of the fill hole you are full. Insert the plug and tighten to 24 lb-ft.

The manual calls for synthetic fluid only - 75W90. The manual states it requires 2.6 pints of fluid, but fill it until it is full.

Yep that would be it. I had my half inch impact on it today. Had the Impact cranked and held it for about a minute. Its a decent dewalt one with 900 ft/lb of breaking force. Didn't even budge. Eventually rounded the entire bolt though. Also had tried heating it with a blowtorch and have had penetrating oil soaking on it for about a week. Soaked it liberally before trying to loosen. Its on there and I give up. I'm taking it somewhere tomorrow. If they can't do anything, I'm taking it back to the dumbasses that put the bolt on and making them do it.
 
Old Mar 12, 2023 | 12:06 PM
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Why not take it to the place that tightened it first? They should remove it for free.

The plastic washer helps to prevent the bolt from from seizing. I am surprised someone would torque it on that tight. Unless they cross-threaded it. Look for that, as that is a MUCH larger problem.

BTW: Never use an impact on bolts like this. Use a long breaker bar instead. And NEVER a 12-point socket. Never!

Also interesting: I tested many impacts before settling on one. On bolts that were torqued with a torque wrench to a precise torque.
Even at specified air feed pressure, most impacts give you maybe 1/2 the torque of what they claim on loosening, and on tightening.
Proof: most have problems loosening a wheel nut torqued to 150ft/lb.

I bought a very expensive Ingersol Rand TiMax. That solved that.
 

Last edited by finall; Mar 12, 2023 at 12:10 PM.
Old Mar 12, 2023 | 01:34 PM
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Got a set of Irwins? Bolt extractor? Chisel? I've had to remove numerous rounded bolts over the years, and never been defeated! YT vid shows many ways I have used over the years:




 
Old Mar 12, 2023 | 02:10 PM
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Pictured above are those were the bolt extractors I spoke about further up in my prior thread.

If you do not have any of these tools, then I suggest you grind new flats onto the bolt, just small enough to fit the next size down socket. Then take an old socket, and pound it on tight. That will remove the bolt.
Unless the morons welded it onto the carrier, LOL!

And DO NOT use a 12-point box wrench pictured above. In fact, never use a 12-point anything, unless you are in a tight spot.
These things like to round off bolts.
Always use a quality 6-point with corner reliefs unless you can't due to not enough turning clearance. Even then, better to use a fine tooth ratchet or stubby instead.
Then repeatedly tap the handle of the end of the ratchet with a hammer, to break the bolt loose. Wear eye protection, as cheapo ratchets can explode.
What you are doing in essence is duplicating a impact wrench, without undue stress to the bolt.

Oh, and avoid vice grips, plumbing pliers, etc. Those usually do not provide enough torque and tend to slip off, and lead to more bolt head or nut rounding. Unless you are using them on bolts less than 1/4" diameter. Speaking from lots of experience.

This bolt can not be on so tight. Especially because it has a plastic gasket. Is there something else going on that you have not told us about?
 

Last edited by finall; Mar 12, 2023 at 02:23 PM.



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