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Whose "Blown Out" the 8 1/4" Mopar Differential?

Dibbons

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I have a Satellite Sebring Plus with the stock 8 1/4" rear end and 2.71 ratio (I have upgraded to sure-grip). I'm not worried when I upgrade the 318 to 340, but thought I would ask anyway about anyone having their own 8 1/4" fail at some time (either from normal wear/tear or [heaven forbid] abuse of some kind or another). Thank you.

2.71 tag.jpg
 
I've blown up two. Non-regular wear and tear.
 
I have worn out the axle and rear wheel bearings in the one in my old half ton pickup. I regularly hauled heavy stuff in it.
 
little tip for you with that axle.
they make aftermarket spacers that replace the original crush sleeves,so you can setup the rear Perfectly instead of trial and error with the sleeve.
as in,if you over torque that crush sleeve,its done,whereas the shims can be used over and over again.
this keeps the pinion from moving around and wearing things out as well.
there Was a difference between early and later 8-1/4s in the pinion Size area too i think.
 
I blew one up early on with my 71 after a few upgrades and lots of abuse
 
I junked four ‘70 Coronets for parts. All small blocks, all high mileage cars. One was a four door that towed a holiday trailer. All still had a good rear end. I wouldn’t hesitate to put one behind a mild small block.
 
I have been running an 8 1/4 , with 4.30 gears and surgrip for years and had no issues running a strong 340 with automatic transmission with 3500 stall tonque converter. At the time the price was right. I built the rear with all new components, no short cuts, but if I was running a standard trans or big block, ( or raced)I would upgrade to a 8 3/4 rear which I have collecting dust .
 
I had 2 wrecked in pickup trucks, I've blown up several 8 3/4's, that's why I go directly to a Dana 60 now if the lesser ones even need a bearing or two. I like to spend once and be done with it. Mind you I run stock 440HP or above for power.
 
When I had the 340 in my 80 R/T I tore two set of spider gears out of her one summer. Use to keep a spare set in the trunk tool box. Certainly not normal everyday wear and tear.
Funny, never had a issue after 340 had a timeout:lol:
 
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