Could someone direct me as to how to identify a mopar axle as far as what size like 8 3/4, whether it came out of a v6 or V8, etc. I have an A body and a C-body axle and that's all I know. Don't know what year, ratio, application etc. Is it possible without disassembly?
A quick picture guide for Mopar rears that I grabbed off the 'net There should be a tag on one of the third-member bolts that has the ratio stamped in it. The one I got from a 67 Coronet didn't have this tag, but I wanted to change the pinion shaft seal and axle seals anyway, so I took it apart and saw the numbers stamped in the ring gear. I've also got a 10-page *.pdf that describes the Mopar rears in greater detail, however, most of it refers to a disassemble unit. If you would like a copy, PM me. Gatz
Ok, so I've narrowed the first axle down to a 7 1/4 from 71-72. Now, how do I tell if it's an 8 or 6 cylinder? It's thick with grease and the 8 3/4 is on the other side of the orchard which is very wet right now so I don't think I'll do any measuring on it tonight.
Saw a row of Aspen/Volares in a junkyard once, the slant 6/sticks were 8 1/4, while the 318/904s were 7 1/4. So on the 7 1/4 it would depend on your tranny if S/B, don't even think about it with a BB. The 8 3/4 should be good for most engines/trannys.
Is that important to know? If you're trying to find out if the vehicle the rear-end came from is an 8 or 6 cyl, the rear-end by itself won't tell you that.
Yes, I have had people wanting to buy it and they always want to know if it's from a 6 or an 8 and I haven't been able to answer them. Thanks George. I'm hoping that'll satisfy their questions.
show them that "Spotter's Guide" If the vehicle that they want to put the rear-end(s) into matches those descriptions, they should be good to go
The only difference between /6 and v8 might be the gear ratio, and the size of brakes is determined by body line (size).
There was no difference between a 6 cyl rear and an 8 cyl rear, some A body 6 cyl cars got 8 3/4 rears and some 8 cyl cars got the wimpy 7 1/4 rear.
The cars got whatever they were ordered with, that includes rear end size, gear ratio, and if it was a Sure Grip (posi). The listing above shows what rear axle assembly was normally used with which cars, motor, & transmission combinations, but were subject to what was checked off on the order form. With Chrysler, never say never, most anything could have been ordered with anything. One time I had a 7 1/4 rear axle out of a 4 door sedan Dodge Dart, the car had 9" drum brakes all around, slant 6 auto trans, and a factory towing package! The 7 1/4 had a Sure Grip unit in it, and 3:55 gear ratio. Only one I ever saw! Paper work in the car showed it to be a specially ordered car. The original owner wanted a cheap bare bones car to tow his boat to the river, and wanted the Sure Grip so it could pull the boat back out of the water when he was ready to go home. I have also had a 65 Barracuda with a factory V8 and a 4 speed that had a 7 1/4 rear axle under it. I can tell you I beat that thing to death and never had an issue with the 7 1/4. A few years after that, I had a slant 6 auto Duster with a 7 1/4, That car had several 7 1/4 rear axles in it, I could break one by stomping the gas pedal with the car in drive. If your selling, that 7 1/4, it is only fairly good behind a slant 6, auto trans car, in my opinion.They are pretty light duty rear axles. If your other rear axle is an 8 3/4, they were tough, and were found in nearly any car between 64 & 74 and behind any motor & trans combo except 440 4 speed or 426 Hemi 4 speeds. Gear ratios for an 8 3/4 range from 2:45 through 4:10. Gene
Chryslers weren't the only ones where you just don't know. I acquired a small tube 8" with 3.0 ratio to run behind my flathead. It had a Detroit locker in it.... Still does with a whopping 100hp pushing it
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