741 rear

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A56

A56

MoPar Affliction
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After crawling under my A56 I find that the rear is a 741 3:23. I'm disappointed a little because I thought it should be a 489. From what I've read 741's came only in low performance cars. I've attached a few photos wondering if someone can tell me what the number 26 indicates. I'm not the original owner so someone may have changed it out. The car is all original up to this point. I've noticed some markings by the universal joint which may not mean anything.

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A previous owner could have swapped center section for better mileage.
Or it could have been born with it...maybe 340 cars didn't get the big pinion center?
Not sure.
 
741s were used in Hemi & other performance cars well before the 742s & 489s existed.

Nothing wrong with a 741 at all. :)
 
340 cars came with the 741. Don't discount it's ability to hold up under a load. 741"s are always considered the red headed step child of the 8 3/4's. They plenty capable.
 
Don't fall for the internet or written BS regarding the weakness of the 741.

The weakness in ALL of them is the same and has NOTHING to do with bearing sizes.

BTW, the 741 doesn't have a stress riser on the pinion like the other two. Seen plenty of 489/742 yokes snapped off right there!
 
Agree with the above. The pinion splines are the smallest diameter on the pinion and the same size as the 742 789. I have a 741 behind a 440 auto in my 69 GTX. Much more likely to snap a u joint than break the pinion.
 
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Well thank you all. I did confirm that it's not an open diff (both wheels rotate in the same direction while spinning either side by hand) and it is a 3:23. I cant make out anything else except the X and the 26.

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We broke a 741 in my brothers car but it nothing to do with the pinion size it was the cap that broke.
 
You can find endless bs opinions on the 741 carrier being weak and to avoid them from most who never: had and broke one, knew someone that broke one, or heard of someone that broke one but in reality probably couldn't find enough to count on one hand actual accounts of one breaking. Just my observation.
 
My matching number 70 340 Duster still has its 741 center section and 3.91's from the factory still going strong after into its 49th year of life.
 
12many said:
You can find endless bs opinions on the 741 carrier being weak and to avoid them from most who never: had and broke one, knew someone that broke one, or heard of someone that broke one but in reality probably couldn't find enough to count on one hand actual accounts of one breaking. Just my observation.
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Inadvertently I've read those stories while researching the rear in this car. I just thought that this Car with the A56 option came with a 489. My previous A56 got thrashed by me plenty in 1969 with no issues.
 
gtgto said:
My matching number 70 340 Duster still has its 741 center section and 3.91's from the factory still going strong after into its 49th year of life.
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This car is #'s matching from front to rear with 116,000 miles, and appears to have the original rear gears in it. Still has markings on the pumpkin and fill hole.
 
My old 69 swinger 340 4 speed came with the 741 323 limited slip from the factory also.
 
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