That whole pinion thing is BS.
Run what you have if it's working and the ratio you want.
Guess which pinion doesn't have a stress riser in it...
Here is a better source for 8.75 info
Pinion Comparison - Quality Body Shop Drivetrain
The 489 is the strongest because the shaft diameter is the largest of the 3 where the greatest load is at. The spline end is not the area of greatest load. That's why it was never changed. The ford uses a third support bearing so the shaft cannot deflect as much. Therefore it can use a smaller shaft diameter. Because the 83/4 does not use this 3rd bearing, the best way to minimize pinion shaft deflection under load is to increase its diameter. IMHO.Yeah...the pinion diameter at the splines is all the same, for all 3 units, as they are interchangable (spline count not withstanding),,,,so....which one is REALLY stronger??????
It all depends on your performance level.It's totally splittin hairs as to which is strongest. End of story.
BS on the pinion size making a difference in strength. It's not the weak point in any of the cases.
Please continue to get sucked in to the false narrative.
Ever seen a 489 case with the yoke snapped clean off? How's that for strength? Never seen a 741 do that.
I did say imho. Did not say they are weak. I said they deflect less under load. I know many guys who start to break gear teeth after certain performance level. Personally I think the Salisbury design overall is superior. ImhoBS on the pinion size making a difference in strength. It's not the weak point in any of the cases.
Please continue to get sucked in to the false narrative.
I be seen a guy with a Dana 60 break a yoke clean off.You can lead a horse to water, but if he's stupid, there's nothing you can do.
I be seen a guy with a Dana 60 break a yoke clean off.
I am just saying that in any instance a larger diameter shaft is alway stiffer and stronger all other things being equal. If you are trying to keep precision machined gears precisely aligned under extreme load, that larger diameter deflects less.Since when are we talkin about Dana 60s?
The solid spacer is a good feature of the 742. I use the aftermarketPersonally I like the 742 housing the best, because it has the largest inner pinion bearing And has no crush sleeve.
I agree with your post. But I was trying to emphasize stiffness and rigidity to maintain mesh alignment. Not outright breakage.489's and 742's break in the same places as 741's do. Been there, done that and seen it many times.
BTW, it was a good design for it's intended use.
I've made dozens of passes with my 7.25, no issuesSince when are we talkin about Dana 60s?
I agree with your post. But I was trying to emphasize stiffness and rigidity to maintain mesh alignment. Not outright breakage.
Most of the breakage I have seen is cap breakage and gear breakage. What other kinds of breakage have you seen.
As you posted most of the time they shuck the teeth off the ring and pinion gear or break the cap on the pinion side.