Stoopid Question About Rear Gear 8-3/4" Pumpkins

[A383Wing]

741 case? 742 case? Differences? Which is better? Isn't there another number?

Inquiring mind wants to know please.

[Ghoste]

Another case is 489 and honestly for the street, they are all just fine.  The primary differences are in the diameter of the input pinion shaft.  Things like the limited slip device changed over the years but for all intents and purposes when people talk about the 8.75, it's the pinion stem that defines them.  What is your final purpose for it Bryan?

[A383Wing]

So, which is which?

I'm thinking of picking up this 741 case rear gear for basically everyday street driving....

[Ghoste]

The 741 has the smallest pinion of the three and generally gets a bad rap for being the "weakest".  I couldn't overstress that it's the weakest of a very durable trio and plenty safe for a street application.  If the price is right, go for it.

[A383Wing]

Ok...that's what I was looking for ....my plan is to put it in either one of the 66 Chargers if we decide to take a trip with the car....like maybe to Mopars At The Strip next year.....

Maybe I can get them at a good price now

Thanks

[RallyeMike]

Besides the smaller shaft and bearing, the main thing people dont like about the 741 is a step in the pinion shaft which creates a stress point. The 742 is also small shaft, but tapered. I've yet to hear of a pinion shaft breaking on a street car.

[Ghoste]

Actually the 489 is the tapered one and the 742 is between the two for diameter.  In any case, you aren't likely going to break it in a street car.

[oldkimmer]

...........741s r fine, u almost never see the pinion shaft break, u will see the teeth ripped off thow as it does on any gear set......All the maxwedge cars+early hemi cars ran 741 cause thats all they had.........My 11.001 duster has had a factory 741  4.10 gear set in for 10 years without a problem..........kim.....

[John_Kunkel]

All the maxwedge cars+early hemi cars ran 741 cause thats all they had

Not so, they always ran the 1 3/4" pinion in either the 742 or the 985 which is the earlier version of the 742. There's no sense having a large pinion if it's not used in high torque applications.