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MooseStang

Well-known member
Joined
Jul 1, 2021
Messages
339
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149
Location
Texas
My Car
72 Q-code Vert
72 L-code Vert
First time for me removing a diff, can't get it separated from the housing. 

Looks like there's black rtv in there.

Any tricks for breaking it loose?

 
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Removed (mostly).  Still not coming loose. Rear end is still in the car, BTW.

What about using a jack to gently break it loose?

 
Well, I don't know how "gently" it was, but I used a jack to slightly lift up the pinion then applied numerous beatings.  Finally broke loose. Letting it drain real good now, will wait till tomorrow to figure out a one man pull out.

 
A jack may work but you'll end up with gear lube all over your jack and floor.  A dead blow hammer on either side of the pinion usually works.  You need to walk it off the studs, so, slight back and forth as it comes out.  Once you break it loose with the hammer, you can use a couple pry bars or large screwdrivers to move it off the studs.

 
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I assume you have the axles pulled out.

I wouldn't use a jack, if you have a lot of pressure on it when it breaks loose it could bend the studs. I use a sharp pry bar and tap it in between the flange and housing in three or four places.

 
I think I should be ok. I took the heavy pressure from the jack away as soon as it started dripping.  

 
Extraction complete. I'm planning on taking it to a local gear shop for rebuild. 

What have I  got here? 

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About the only thing I can tell you is that the C7AW-E is a 9-inch carrier that was used for  several years on a variety of vehicles. 

If the ID tag was missing it is likely that someone has been in there before, and hard telling what they did. I couldn't find that ring gear number in my car parts manual, and I believe that the TW on the ring gear means the ring and pinion, at least, are from a truck.

Maybe @Secluff will chime in with more information.

 
Differential is a traction lok unit - by the counterbores for the ring gear bolts. Open diff will be flat in this area. 

If you end up replacing the gear set, be sure to source a USA made ring and pinion, and that it's a known quiet model. Lots of the R&P out there today are made overseas and are very noisy. 

 
When I spoke to the guy at the gear shop, I mentioned that I was thinking of changing from 3.50 to 3.25 . He said that a quality gear set in that ratio was difficult to get,  and he was suggesting a good quality used set. Not sure if that's true or not. He is giving me a 1 year warranty. 

Another pic.

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When I spoke to the guy at the gear shop, I mentioned that I was thinking of changing from 3.50 to 3.25 . He said that a quality gear set in that ratio was difficult to get,  and he was suggesting a good quality used set. Not sure if that's true or not. He is giving me a 1 year warranty. 

Another pic.

View attachment 55416


I would be looking for a different shop. All the major gear manufacturers make a 3.25 gear set.  Sounds like he is just trying to sell you a used one he has.

 
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3.50 is a great all around gearset, not sure the 3.25 switch will really gain you anything except a few less RPMs on the highway. 

Maybe call Quick Performance and talk to them about which gearset brand and part # they recommend. 

These guys have an excellent reputation as well. 

https://8and9inchfordrears.com/

 
I've always found this 'Painter's 5-way' tool extremely useful to carefully tap between housing and  third member unit to break the sealant bond.

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Hey Bill- I have no idea what that tool is made for but it is one of the handiest tools that I have! Had a buddy give we one years ago!

 
Hey Bill- I have no idea what that tool is made for but it is one of the handiest tools that I have! Had a buddy give we one years ago!
Probably the most useful all around tool on my work bench

 
Thanks for all of the advice.  This shop has some good reviews, perhaps I didn't get all the information accurate.  I'm probably going over there today or tomorrow, I'll insist on a new set of USA made gears & parts.  

That tool would be perfect, just needs to be slightly modified to incorporate a bottle opener.

 
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