8&3/4 spline count Q

[Rapid Robert]

have an OE 489 pig, not sure of the ratio . want to swap in an Ebay 4:10 489 case r&p with a 10 spline count. will the spline count be the same? thank you for your time.RR

 

[sireland67]

Most likely stock would have 29 spline.

 

[Oldmanmopar]

No.

 

[jimjimjimmy]

it could be either one , 1 1/4 nut is 29 spline and 1 1/8 is 10 spline , this is nut size .

 

[Rapid Robert]

Jimmy you're the man! I will check the nut size. thanks a bunch guys. RR

 

[forphorty]

I think almost all aftermarket r&p are 10 spline. New yokes are readily available. Super duty FORGED STEEL 7290 U-bolt yoke

 

[Rapid Robert]

^^^ 440 I may have to grab one. RR

 

[str12-340]

here's the whole break down for coarse (10 spline) and fine spline (29 spline)
742 (1964 to 1972) - 1 3/4 pinion coarse
741 (1964 - 1972) - 1 3/8 pinion fine
657 (1957 - 1964) - 1 3/8 pinion coarse
489 (1969 - 1974) - 1 7/8 pinion may be coarse or fine

 

[Rapid Robert]

^^^ good comprehensive info. I will be useing the 489 pig that I have so I will confirm coarse or fine & go from there. RR

 

[Rapid Robert]

nut size is 1&1/8 so 10 spline coarse so the Ebay 4:10 gearset I was looking at will work , thanks guys! RR

 

[Rapid Robert]

the pig I have close by turns out to be a 741 not a 489. I dont see any ebay gearsets for a 741 but I see em for 742. will 742 gears work in a 741 pig? thank you for your time. RR

 

[jimjimjimmy]

the pig I have close by turns out to be a 741 not a 489. I dont see any ebay gearsets for a 741 but I see em for 742. will 742 gears work in a 741 pig? thank you for your time. RR

no

 

[Rapid Robert]

thank you Jimmy