ghostrider

Anybody know what the final drive ratio is on a 98 f150 2wd with the manual trans and a 4.6 is? Trying to figure what it will be turning with a gear swap.

CPT150

according to the manual it says 3.55

jferg92

Look at the axle code on the door jam sticker

ghostrider

I'm sorry the trans final drive ratio not the rear.

SR2K

4th is 1:1 I think 5th is 0.71:1

CPT150

you know there are final drive calculators out there

ghostrider

Lol, my tach is off a few hundred rpm I think. So i'm not sure what its currently turning. Just trying to find out what 4.11 or maybe 4.30's would be.

ibd2328

iTrader: (2)

.71*3.55= 2.52 so it takes 2.52 revolutions of the enginge/drive shaft to turn the wheels one complete turn.


.71*4.10=2.91 around 20% increase in RPM's at this gearing at the same speed as the 3.55 with same tires


.71*4.30=3.05 around 26% increase in RPM's with this gearing at the same speed as the 3.55 with same tires

ghostrider

Thankyou sir

ibd2328

iTrader: (2)

No problem.. If i knew tire sizes you wanted, I could calcuate Rpm within 10% just need to know the loaded height of the tires or revs per mile