Originally Posted by TCP_Ranger
ok so between the 3.55 and 3.73 whats any big difference. ive tried to learn about gears and such but i just end up getting confused. lets just go with the 3.73. would i feel much of a difference in acceleration from my 3.08? if i understand this 3.73 would give me better accel because rpm's would be higher but it would also cut my top speed.
if you went up to a 3.73:1 gear ratio you would see an increase in rpm, but a decrease in fuel economy because your engine is now working harder to turn the smaller gear to maintain the same speed.
something no one mentioned is that the "3.73" refers to what is called an underdrive ratio ( a 0.90:1 or less is considered overdrive). in other words, your drive shaft turns 3.73 times for every one revolution of the wheel. to lower the mpg, you would want to probably drop the ratio to less then what you have now, something like 2.90:1 or smaller.
have you factored in the cost as well?? parts and labour??
really the only time you should be changing out the gears, is when you change other factors like tire size and trans ratios which effect your final compound ratios of your driveline/powertrain. if your truck came with 225 and 3.08:1 gears then im sure someone got paid allot of money and spent allot of time in research and development to determine an ideal size that would give the specific vehicle the right balance of torque and acceleration.
just my 2 cents.
Form follows Function
1994 Mazda B4000 4x4, Ford Camper Shell FTW, 31x10.5 Duratrac's, 15x8 Daytona's