Gear ratio question

195 views
7 replies
6 following
K
Gear ratio question
unclecorntooth avatar
unclecorntooth
+1y
could someone school me on how to find out the gear ratio of a rearend. I know you can figure it out by turning the input shaft and seeing how many times the axle turns but dont know the ratios....or if there is another way im curious to know that also.

unclecorntooth avatar
unclecorntooth
+1y
no one???


olskoolpup avatar
olskoolpup
+1y
if its your factory rear end, check the owners manual.

to find out manually, rotate the input shaft. have a mark on the shaft as well as a fixed point on the rear end housing near the shaft.

make a mark on the rear brake drum, and on the backing plate.

rotate the input shaft until the the mark on the drum goes around once, while counting how many times the the input shaft goes around.

youll be in the neighborhood of 3-4 revs of the shaft to 1 rev of the wheel. itll get you close at least.
thacru78 avatar
thacru78
+1y
I think you can open up the differentail cover and count how many teeth are on the big wheel and how many teeth are on the small wheel. Divide the 2 and that's your gear ratio. I think you can...but i'm not sure if it works like that.
unclecorntooth avatar
unclecorntooth
+1y
thnkas
turboh22aakkord avatar
turboh22aakkord
+1y
Originally posted by thacru78



I think you can open up the differentail cover and count how many teeth are on the big wheel and how many teeth are on the small wheel. Divide the 2 and that's your gear ratio. I think you can...but i'm not sure if it works like that.

yeah... there is a formula that you can use to get your gear ratio that does involve counthing the number of teeth on the ring and the pinion, i just cant remember what it is... google that shit! haha
lester622 avatar
lester622
+1y
Originally posted by unclecorntooth



could someone school me on how to find out the gear ratio of a rearend. I know you can figure it out by turning the input shaft and seeing how many times the axle turns but dont know the ratios....or if there is another way im curious to know that also.





the way u talkin about is alot easier then countin the teeth go to www.jegs.com and they got most of the gear ratios listed
baggedchevy1 avatar
baggedchevy1
+1y
the gear ratio is markrd on the ring gear (the big one) it should look something like this 14:43 (witch are the ones on mine the ratio is 3.07 or 3.0 stamped on the edge of the ring gear divied the big # in to the small one and that will be your gear ratio then we can go in what series the third member 2 3 or 4 series