7 1/4 Rear End in 69 Barracuda

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Stukenbroeker

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Hey guys, just got word from the shop that my ring and pinion gears are shot in the stock 7 1/4 rear in my 69 Barracuda. They said they can rebuild the rear and to expect around $1500-$2000. This seemed pretty steep to me, and led me to a few questions:

Would it be smarter to look for a 8 3/4 to swap?
If so, what's needed for the swap? Does the 8 3/4 bolt right in?

This isn't a drag car, it's a daily driver, so I'm no opposed to just replacing the gears in the current rear, as money is a factor here.

The only gears I have found for the 7 1/4 are around $190.
Does that sound about right? Can't find much info on the 7 1/4.
I'm pretty familiar with the ring and pinion swap process, but if there's something tricky about the 7 1/4 I'd appreciate any input!

Thanks guys!
 
That's way outta line.. A gear set is less than $200,, brgs , seals, gskt -$150..

The "Chilton" ref book gives 5.4 hrs (factory time -4.2) to replace ring, & pinion, axle seals, pinion seals, change bearings, (same to replace).. ( I'd ask how many hrs they're charging)''

At $100 an hour, thats $540; plus parts, the bill should be in the neighborhood of $940.. + taxes..

A good used 7 1/4 rear from a member should be $100 or free ( I have one of several you can have but shipping would kill you, someone closer will likely have,, one..)..

8 3/4 are rare and expensive..

An 8 1/4 rear end outta a newer A Body is what you need if you feel an upgrade is nec.... They're fairly easy to find,, cost $200 bucks,, and fits right in,, with a driveshaft mod ($100), which you would have to do for the 8 3/4 anyway.

Hope it helps
 
Hell I'd give you my 7 1/4 if you were closer. They aren't very hard or expensive to find.

But I would change it out with an 8 1/4 or a 8 3/4 if you can find one. Much stronger, and reliable.
 
First I'd change the rear no question about it.
Second understand that the 8.75 rear from an a body will be a small bolt pattern (which is the same as your front 5x4), unless someone swapped them/re-drilled them. Now if you don't mind the big bolt pattern a b body 8.75 it fit as well but you'll need to move the spring perches in 1/2" each side and you'll need different rims with more backspacing but the b body rears are muh cheaper vs a body 8.75 (also finding the brake parts for a body 8.75 with stock setup is a real *****).
Third is the 8.25 rear from a 73+ a body (know this now the 8.25 ONLY came in the BIG bolt pattern 5x4.5), these can be found for cheap just know that the 2.71 ratio and down (numerically lower) is a different setup from the 2.91(? Or is it ratio 2.94 either way 2.9+ is the one to grab) and up (numerically higher) but again the 2.9+ is the rear you want and here is why. You can acquire more part for cheap/junk with 2.9+ ratio 8.25 a body rear. Once you get that 8.25 a body rear go to the junkyard and find a 1996 and older jeep grand Cherokee. Once found open the rear diff cover and see if it is a limited slip diff. If so take out the limited slip unit and gears as well (most of the time the jeep will have much better gears than what's in the a body 8.25). If the jeep also has rear disc brakes take that setup as well. All these parts you just took will bolt directly to the a body 8.25 rear. once done This will give you an a body 8.25 with some very decent gears with a limited slip unit and rear disc brakes.

Finally, if you opt to upgrade to the either the 8.25 or 8.75 will need to do a few things.
1. You will need new/different leaf springs
2. You will need new/used shock mount brackets for the 8.25/8.75 because the 7.25 has a smaller diameter tube compared to the 8.25/8.75 (which are/share the same diameter tube).
3. You will need to have your driveshaft shortened or replaced for the 8.25/8.75 rear.
4. This one is optional depending on what brake setup you have up front (drum) you might wanna look at converting to front disc brakes. If you want to keep the small bolt pattern you can get the scaredbird setup or the factory K/H setup. If you don't mind converting to the big bolt pattern just look for the 73+ setup. The big advantage the big bolt pattern has over the small bolt pattern is a much much wider wheel/rim selection (which also means a bigger tire selection), much much cheaper/easier to find brake parts, less maintaince, and will just a caliper adapter (don't even have to disconnect the brake line) you can run 11.75" front rotors vs the stock small bolt pattern 10.87" rotors which more stopping power. If you go this route of big bolt pattern brakes, just get the sliding calipers off a 77-78 roadrunner because they have a bigger piston diameter in them.

I know way more info than you wanted/needed to know but you said you daily drive the barracuda and just but upgrading to front disc (and rear disc or bigger rear drums) you'll have a much much better stopping distance. Safety first enjoy.
 
If you don't beat it up I'd do as Inertia suggests, if you do beat it up I'd get several cheap 7 1/4, they are free to really really cheap!:burnout:
 
For $1500-$2000, your mechanic is trying to rip you off BIG TIME. You could score an A-Body 8.75 with new axles for MUCH less.
 
Thnx 1970Duster,, I'd forgotten about the bigger axle tubes needing the larger U-bolts and shock plates.. cheers

I Dis-agree on needing new springs,, just the U bolts and shock plates are nec..
 
Upgrade from the 7 1/4 is normal amongst the A- body crowd.Find a used 8 1/4 or 8 3/4 for cheaper.Heck I have a Dana 60 built in my car for 2k...Look in the Mechanical parts for sale forum for a better deal local.
 
7.25 rears area dime a dozen. Granted the correct small bolt pattern rears in better condition aren't laying around everywhere.
If you were willing to change to large bolt pattern,
Up to 1976 builds will bolt right in and probably in good used condition too.
Bottom line... don't spend a dime on the rear you have.
 
Thanks for all the responses. Seems like the consensus is ditch the 7 1/4 that's in there. I wish there were more yards in the area with old mopars. :(

Guess it's time to start searching
 
Try placing a "want ad " on this site,, I'm surprised you haven't had a few more offers already...

hope it helps
 
1970Duster said:
Finally, if you opt to upgrade to the either the 8.25 or 8.75 will need to do a few things.
1. You will need new/different leaf springs
Click to expand...

Why can someone explain? Also we need a write up and sticky for this type question. Stating this is what you need, why you need it and how to do it. Craig
 
Originally Posted by 1970Duster
Finally, if you opt to upgrade to the either the 8.25 or 8.75 will need to do a few things.
1. You will need new/different leaf springs
Click to expand...




my5thmopar said:
Why can some explain?
Click to expand...

I'm curious as well, I went from a 7 1/4 to an 8 3/4 and used the same springs. :dontknow:
 
Springs have a leaf or 2 more , u bolts and mounting plate are different
 
Well, the car the 8 3/4 came out of had the same amount of leafs mine did. I realize the shock plate and U bolts are different, but they still bolted right up.

I dunno, maybe I missed something along the way, it wouldn't be the first time.
 
not exactly so. My 68 notch has 6 leaf springs under the 7.25 rear, all OEM.
Those leaf springs are the only difference from my 67.
 
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