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Discussion Starter #1
HELP!!!
I broke my rear axles.....
need a set of 28 or 31 spline to fit my 69 cat
also possible pig unit


Should have seen the burn out though!!!!!!!!!!!!!!
 

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How in the world did you break both axles? Normally if you break one, all the power goes to the one with the least resistance, ( the broken one) unless you're running a spool.

If you break a ring gear, or the pinion gear, it would mimic breaking both axles.

Breaking an axle is very rare for a street car, however, if you were getting wheel hop, yes, you could break an axle, but probably you'd break some teeth of the ring gear first.

I have several friends who drag race on a serious level. They have never broken a stock 28 spine axle. They have, however, broken both stock 31 spline and aftermarket 35 spline axles! The 28s will twist almost a full turn before they break. The 31s and 35s just snap right off! Believe it or not, I had a 71-3 Cougar 9" rear in my 74 Camaro race car with stock 28 spline axles. I was picking up the front end a good three feet and running low [email protected]+mph. They didn't even take a twist!

The broken 31 was in his Boss 429 when he bought it. He bought that car as a motor-blown-up drag car. Swallowed a couple of valves, broke rocker arms, punched out four combustion chambers with the debris flying back and forth across the inside of the intake manifold. What might have happened was that the axle let go first, causing an over-rev which killed the motor. This blow-up happened way back in the early 70s before rev limiters.

The 35 spine breakage occured in a 71 Mach 1 with a 514-inch motor and an automatic! I never thought that an automatic car would put that kind of stress on the parts! Yes, the car goes 10.90s, but sheesh. Of course, what is not helping matters any is that the car is heavy. It still retains the full stock interior, radio, heater, etc. The car is even street legal with street tires! Anyway, I suppose that much torque trying to move that much weight might cause some stress, eh? BTW, he's also broken some of the teeth of his ring gear too!

I have several pigs laying around here. 2L75, 3L00, 3L25 28-spline and a 3L50 31 spline. No axles though. Also have a set of 3.91 gears.

Since you're in central OH anyway, can't you just wait for the fall SuperSwap in Columbus? You might find axles there. I know there are several vendors that have pigs all set up and ready to go...
 

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axles

Hmmm I wonder if he had 8 inch axles and not 9" as they fit but are thinner. You can get the axles from Fairlane Comet 66-70 Cougar or Mustang 67-70 :)
 
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