Differential Gear Ratio Help Needed

[BLACK MOON]

I'm selling my spare differential and need help figuring the gear ratio. The ring gear is stamped "3733908 9:?7". Any help would be appreciated. Thank you

 

[Tuna]

Have you tried counting the teeth on the ring gear and pinion gear and then dividing?

 

[BLACK MOON]

Can't really see the pinion gear.

 

[Mac]

Mark both the pinion and the side yoke, spin the pinion and count how many complete revolutions are required to make the side yoke spin one complete revolution.. Based on the number you gave, I'm gonna guess it's a 4.11...

Mac

 

[BLACK MOON]

Thanks all. I'll try that.

 

[JohnZ]

Thanks all. I'll try that.

It's a 4.11. 9:27 would be 3.00:1, and that never existed (and wouldn't work due to the even tooth count). 9:47 would be a 5.22:1, and that never existed. 9:37, however, is 4.11:1, and that's the OEM tooth count for the 4.11.

 

[navy2kcoupe]

9:27 would be 3.00:1, and that never existed (and wouldn't work due to the even tooth count).

John, I'm gonna plead ignorance here and ask for a little help in learning something new!
Why won't the even tooth count work? Is it because tooth 1 on the pinion gear will ALWAYS
contact tooth 1, 10, and 19 on the ring gear, and that's not something advisable? I can see
that the odd tooth count will allow any 1 tooth on the pinion to cycle thru all the teeth on
the ring gear, but that's the only thing I can come up with. Is there another reason?
Thanks in advance for any help !
Andy Anderson

 

[Mac]

It's a 4.11. 9:27 would be 3.00:1, and that never existed (and wouldn't work due to the even tooth count). 9:47 would be a 5.22:1, and that never existed. 9:37, however, is 4.11:1, and that's the OEM tooth count for the 4.11.

That's twice I've been right this year and it's only September... Maybe I can squeeze in another one... :eek

Mac

 

[navy2kcoupe]

Look out Mac....... your head will get so big that your hat won't fit,
and with winter approaching, you NEED your hat to fit! :L
Andy