Doorkicker
Well-Known Member
This is more of a curiosity type of question and potentially a very obvious answer.
Going down the road - nothing special, 45 mph, cruising - and suddenly a very loud grinding noise came from the rear. It stopped and then did it again. Was only a mile from home. Pulled apart to find the shaft retaining roll pin was sheered and the shaft had drifted into the pinion gear. The pinion gear actually faired well. Not only did I find a shattered roll pin, but even the remains of someone's tool used to put the pin in.
The rear is a 742, 3:23, and the car is well into the 650 hp range (I'm building a new 489 3:55 sure-trac II, hence not worried about this rear). I haven't beat on it. Still letting the engine break-in and getting into its rhythm.
So, the question is: What would cause the roll pin to just sheer inside like that? I would think it would require serious rotational forces placed on the shaft, but how would that occur? The spiders rotate around the shaft, so did one lock onto it? The spiders turn freely on the shaft currently. What am I missing? Or, is it just one of those things that happen sometimes... Drop some of that killer Mopar knowledge on me.
aTdHvAaNnKcSe
Going down the road - nothing special, 45 mph, cruising - and suddenly a very loud grinding noise came from the rear. It stopped and then did it again. Was only a mile from home. Pulled apart to find the shaft retaining roll pin was sheered and the shaft had drifted into the pinion gear. The pinion gear actually faired well. Not only did I find a shattered roll pin, but even the remains of someone's tool used to put the pin in.
The rear is a 742, 3:23, and the car is well into the 650 hp range (I'm building a new 489 3:55 sure-trac II, hence not worried about this rear). I haven't beat on it. Still letting the engine break-in and getting into its rhythm.
So, the question is: What would cause the roll pin to just sheer inside like that? I would think it would require serious rotational forces placed on the shaft, but how would that occur? The spiders rotate around the shaft, so did one lock onto it? The spiders turn freely on the shaft currently. What am I missing? Or, is it just one of those things that happen sometimes... Drop some of that killer Mopar knowledge on me.
aTdHvAaNnKcSe