So how can I tell what spline 489 I've got?

MilesnMiles · Post by **MilesnMiles** » Tue May 05, 15 8:11 pm

I know they come in either 10 or 29 spline. Is there an easy way of telling without ripping things apart?

challenger · Post by **challenger** » Tue May 05, 15 8:37 pm

if its got a none crush sleeve pull the yoke off but if it has be carefull as you will loose pinion pre-load. its the only real way to tell unless you know what make of gears i.e motive,richmond,strange

MilesnMiles · Post by **MilesnMiles** » Tue May 05, 15 8:48 pm

Oh bugga thanks Jim! I believe it's the original 3.23 set but it was rebuilt before I got it.
If it's a 73 correct diff it should be 29 spline.
If I change the gears presumably all I have to do is have a matching yoke. Is that correct?

challenger · Post by **challenger** » Tue May 05, 15 8:55 pm

mines a 72, 489 and those were 29 spline on a 3.23, the motive gears i brought were 29 spline, what gears you going for as i have a couple of sets with matching yokes, there used but in good shape (7290)

Jon Connolly · Post by **Jon Connolly** » Tue May 05, 15 8:59 pm

90 % sure it is a 29 spline Miles

MilesnMiles · Post by **MilesnMiles** » Tue May 05, 15 11:08 pm

Thanks chaps, thinking of 3.55 or 3.73

charger01 · Post by **charger01** » Wed May 06, 15 12:25 am

Still got my b -body 8 3/4 here with 3:55's , 489 case. Wont split if anyone wants the hens teeth of axles. Open to offers.