Gear ratio in transaxle how to calculate.

[dangerous]

I open one transaxle, I saw a number of gear, from input shaft that meshed in the mainshaft and on the mainshaft 4th counter gear there is intermediate shaft with gear, at the end of that shaft also got one gear which is the pinion gear meshed in the ring gear. now which of those gear meshed i need to calculate to get the overall gear ratio for the speed gear i choose example is 3rd gear speed. the number of teeth of them.

3rd gear = 36/28= 1.285
Intermediate shaft with gear= 34/30= 1.133
Pinion and Ring gear= 67/17= 3.941

which of these i need to calculate to get the overall gear ratio for 3rd speed gear.

On gearboxes with countershafts, or planetary gearboxes like the lenco
you need to multiply the ratios of meshing gear sets together.
So in the above example,(just guessing without a picture of your example),
1.285 x 1.133 = 3rd gear ratio.
Them multiply by the R&P ratio gives the overall ratio.

Volksies are very simple,
you just divide the driven gear (DN), by the driver gear(DR) which gives the ratio,
them multiply by the R&P ratio gives overall ratio.

[dangerous]

marc has explained it just ahead of me.

[trinity]

can you explain to me how you get (34x36x67)÷(28x30x17) = 82008÷14280 = 5.74285714.

the formula? why 34 multiply in 36 and 37?

the one i open is transaxle not transmission. can you calculate for me example the final gear ration of this:

3rd gear: 36 teeth and 28 teeth

intermediate shaft: 34 teeth and 30 teeth

ring gear and pinion gear: 67 teeth and 17 teeth.

the power flow will be from input shaft to the 3rd gear speed into layshaft fixed 28 teeth, into intermediate shaft 34 teeth into 30 teeth going to the pinion gear teeth 17 into ring gear 67 teeth. what is the formula for final gear ratio. thank you.

[Marc]

trinity's now resorted to pestering me with PMs. I've asked him to read the link I provided and again pointed out that this is not an appropriate forum for his question.
Below are examples of his thought processes, provided as a warning to anyone else who's thinking of entering this quagmire (be prepared to also offer remedial math tutelage).

" the power flow will be from input shaft to the 3rd gear speed into layshaft fixed 28 teeth, into intermediate shaft 34 teeth into 30 teeth going to the pinion gear teeth 17 into ring gear 67 teeth. what is the formula for final gear ratio."

"(34x36x67)÷(28x30x17) = 82008÷14280 = 5.74285714... in this final gear ratio it means the 5.7:1 is the ratio, meaning the engine must turn 5.7 in order to turn the wheel 1 turn right?

i calculate mine and its came out 6.25 the final gear ratio.
so it will become 6:1 ratio

but when i apply it by turning the engine it should be 4 times only to turn the wheel 1 times. at 3rd speed."

[ttriebler]

Formula to calculate overall gear ratio on whatever gear you have selected :
(input shaft gear teeth / output shaft gear teeth) x (ring gear teeth / pinion teeth).
That's it. Simple.

[Marc]

Formula to calculate overall gear ratio on whatever gear you have selected :
(input shaft gear teeth / output shaft gear teeth) x (ring gear teeth / pinion teeth).
That's it. Simple.

Simply WRONG. The number of driven (output) gear teeth should be divided by the number of drive (input) gear teeth, not the other way 'round.
Take the case of a 1st gear with 10 teeth on the mainshaft and 38 on the pinion shaft. That's a 3.80:1 ratio. Divide 10 by 38 and you get the inverse, ~.26:1.
trinity is confused enough already, this isn't helping.