7.25 rear woes....

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pishta said:
I'd say a SG model would handle everyday driving no problem in an automatic. Manual has more shock to it, so they put 8.75's In 4bbl manuals starting in mid 65. Don't know what happened when Mopar put them.back in the 67 4sp 3.91 geared Bartacuda. Possibly the taller gear puts less leverage on the weak spider gears.
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Again showing my ignorance but SG? That spider gear? I have an automatic btw dont think i mentioned but am putting 4 barrell in.
 
Keep hunting for a more rubust rear end. I've got a pile of 7 broken 7-1/4s behind my Mom's garage and a couple next to my shop. Anything that loads up one side abruptly will rip the spider gear shafts out of the housing. I've torn up a couple with slant sixes turning corners in ice/snow. I put 7-1/4s back behind the sixes but always upgraded the axles behind a V8 because of my experiences.
 
Go with the Ford 8"rear. Parts are plentiful, way stronger then the 7.25 and have the dropout center. Makes it easy if you ever want to change gears. Plus you have options on limited slip, locker or spool. I got mine out of a Maverick, but I think the early Mustangs (64.5-66 or 67-68) used the same rear so they are available.
 
I ran my old 7 1/4 open rear for 6-7 years with my 360/350 HP 904 trans. During that time the car saw more than a few smoky burnouts with no problems what so ever, rear tires were 265/60-15. Now I changed to a 8 1/4 sure grip with 3.55 gears.
 
None2Slow said:
Go with the Ford 8"rear. Parts are plentiful, way stronger then the 7.25 and have the dropout center. Makes it easy if you ever want to change gears. Plus you have options on limited slip, locker or spool. I got mine out of a Maverick, but I think the early Mustangs (64.5-66 or 67-68) used the same rear so they are available.
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Does this have to be narrowed? Im really hoping for something that is as close to plug and play as possible.
 
leblanc said:
I ran my old 7 1/4 open rear for 6-7 years with my 360/350 HP 904 trans. During that time the car saw more than a few smoky burnouts with no problems what so ever, rear tires were 265/60-15. Now I changed to a 8 1/4 sure grip with 3.55 gears.
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I may have to risk it since ive searched for a local 8.75 or 8.25 that will fit with no luck.

Im just super paranoid about it breaking soon after i dump what money i have into it.

Gonna be about 4 more years before i have the budget again to do something else to this car and want it to last!
 
My ignorance is also a crutch.

Saw this just now
[FOR SALE] - 1969 A Body 8 3/4 rear end

Does this discription mean i would need to buy the “chunk” or “pumpkin” or center piece or whatever and can i put disk brakes on it?

Is this the kind of thing i should keep my eye out for or a complete one?
 
grimreaper said:
Keep hunting for a more rubust rear end. I've got a pile of 7 broken 7-1/4s behind my Mom's garage and a couple next to my shop. Anything that loads up one side abruptly will rip the spider gear shafts out of the housing. I've torn up a couple with slant sixes turning corners in ice/snow. I put 7-1/4s back behind the sixes but always upgraded the axles behind a V8 because of my experiences.
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Thanks for the advice!
 
73dartswingerlover said:
My ignorance is also a crutch.

Saw this just now
[FOR SALE] - 1969 A Body 8 3/4 rear end

Does this discription mean i would need to buy the “chunk” or “pumpkin” or center piece or whatever and can i put disk brakes on it?

Is this the kind of thing i should keep my eye out for or a complete one?
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Yes you would need a center-section
I wouldn't bother with retro-fitting rear discs brakes. Typically the rear brake system does less than 15% of the total braking. Even small Drums can easily handle that.
There are two things that kill a 7.25; peg-legging it and shocking it. Three if you include old contaminated oil. If you put a SG in it, that kindof eliminates the former. The auto sortof eliminates the later. If you can refrain from doing neutral drops, you might be surprised how long the 7.25 lasts. I had one for years behind a 340 auto.
245s are about the biggest tires you can put under there without moving the springs and getting custom wheels, so that is a non issue. Even less of an issue if you put them on the factory narrow wheels
 
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AJ/FormS said:
Yes you would need a center-section
I wouldn't bother with retro-fitting rear discs brakes. Typically the rear brake system does less than 15% of the total braking. Even small Drums can easily handle that.
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Awesome thanks! That will save $$.

I went ahead and posted in the wanted section and will just have to hope someone has one they wish to sell me.

Anyone know the going rate that would be fair for one of these?

Either 8.75 or 8.25 SG?
 
A would say a complete good usable 8.75 for an A body is going to run you close to $1000. An 8.25 probably half that. I got my 8" off of craigslist for $20, yes $20. Local yards here want about $250 or so. The last A body bare housing I saw had an asking price of $900. $300 for the axles and $600 for the sure grip center. For that kind of money I would have done a custom 9" and had new parts.
 
None2Slow said:
A would say a complete good usable 8.75 for an A body is going to run you close to $1000. An 8.25 probably half that. I got my 8" off of craigslist for $20, yes $20. Local yards here want about $250 or so. The last A body bare housing I saw had an asking price of $900. $300 for the axles and $600 for the sure grip center. For that kind of money I would have done a custom 9" and had new parts.
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Holy hell 1800 would be way too much imo for a used one. Hopefully i can find one closer to your other estimates.

Once you get to 1800 you are getting close to a new moser rear lol.
 
Possibly locate 1 in a local you pull it type yard. These rears bolt in, but the spring locating pin needs to addressed. Either use a bushing to fill the space, or take yours out and drill it bigger to fit the Ford. Either way, not a big problem. You will need to address the driveline as it will most likely be longer and the U joint is a different size. When the time comes I will need to have 1 made anyways because Im going from a manual to an auto and the old driveline has the CV style joint and I need the slip yoke instead. At that point I will have them add the correct end to whatever I use at he time.
 
None2Slow said:
Possibly locate 1 in a local you pull it type yard. These rears bolt in, but the spring locating pin needs to addressed. Either use a bushing to fill the space, or take yours out and drill it bigger to fit the Ford. Either way, not a big problem. You will need to address the driveline as it will most likely be longer and the U joint is a different size. When the time comes I will need to have 1 made anyways because Im going from a manual to an auto and the old driveline has the CV style joint and I need the slip yoke instead. At that point I will have them add the correct end to whatever I use at he time.
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Every junkyard ive talked to locally says they dont have any old mopars. Unless we are talking about doing the narrowed ford 8.8 swap.

I can find those easily just no 8.75 or 8.25 for an A body.
 
Im from Dana so may have crossed paths. Not wanting to part with my stuff but just a heads up on charlotte, its going on right now. Im actually sitting in my spaces as i type. Tomorrow will probably be the best day. And fyi ive only seen 3 people with mopar stuff so far. You will find farmington swap meet and drags in may to be a mych better chance of finding what youre looking for.
 
sawdoff said:
Im from Dana so may have crossed paths. Not wanting to part with my stuff but just a heads up on charlotte, its going on right now. Im actually sitting in my spaces as i type. Tomorrow will probably be the best day. And fyi ive only seen 3 people with mopar stuff so far. You will find farmington swap meet and drags in may to be a mych better chance of finding what youre looking for.
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Thanks for the heads up.

The reason that there is a mopar shortage on this side of the world is because i now own one.

If i got rid of it tomorrow there would be 10 for sale almost immediatly!
 
Thank you all for your advice and help.

Unless if falls through i think i have just what i need lined up!
 
Good, hope it works out. If it doesn't, trust me any idiot can shorten an 8.8 furd. I did. Seriously, if you can change spark plugs you can do it. Even if you spend a little more having a driveline shop shorten the tube and re-weld your perches, it'still very economical and a sturdy diff. JMO.
 
moparmandan said:
Good, hope it works out. If it doesn't, trust me any idiot can shorten an 8.8 furd. I did. Seriously, if you can change spark plugs you can do it. Even if you spend a little more having a driveline shop shorten the tube and re-weld your perches, it'still very economical and a sturdy diff. JMO.
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Awesome. Ill keep that in mind for future but i think i have an abody 8.75 lined up.

If it ever breaks or whatever how mich is a ballpark figure for the shortening and perches being done at a shop?

I like what i got going on now but always nice to have a backup plan since those ford rears are everywhere.
 
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