hi sages- just read an interesting post on the board about differential gear ratios in 240s. got me thinking about the final drive ratio in my 92 240 wagon. the final drive is the diff gear ratio times the highest gear in the trans. i am not sure but i think the standard diff gear in the 92 240 with manual 5spd(m47) is 3.31. 5th gear in this trans is an overdrive which i think is .80 so final drive in this setup would be the product of these two ratios or 2.6. i have a 76 plymouth feather duster with a slant six and a 4 speed overdrive trans. this vehicle has a 2.94 diff gear and a .73 overdrive in 4th speed producing a very high final drive ratio of 2.15. in fact that is the highest final ratio i have seen in a production car with rwd and a manual trans with overdrive. both cars get high gas mileage (volvo about 28 mpg and duster about 26). im sure of the dusters gear ratios but not the volvo. these gears would account for the high mpgs. it is very easy to lug both of these cars in top gear if you dont shift down soon enough. the duster has more power and torque than the 4cyl volvo which is probably why the volvo has 5 not 4 forward speeds and the lower diff gear and slightly lower od gear. am i right about the 3.31 diff and .80 od in the 240? thanks and hope my analysis is correct, oldduke