I have a 95 f150 4.9 I6. I put 33's on it and i'm wanting to change the gear ratio. it currently has 3.55 gears and i'm wanting to go to something around 4.10's. My problem is that, for example, 4.10's are available for the rear but can only find 4.09 for the front in the same brand of gears.

Is this common? would .01 make any difference?

Also www.4lo.com states that somthing around 4.10's would restore the torque and RPM's to somewhere around factory.

Does anyone know if changing the gears alone would change the speedo on an electronic speedometer control?

Thanks...

 

yah you'll have to recalibrate your speedometer if you go with lower gears. But i don't think i'd put different gears in the front than in the back unless i was doin mud runs. It just seems to me like it would be hard on everything having the front wheels spin faster even if it is .01. It'd probably wear out your tires alittle faster. I'm not completely sure but you'd be better off making sure you do it right the first time than having to go back and do it over again

 

Hi Rockhound,

I had the same problem. I ended up replacing the whole front diff with a larger housing to accomodate the 4:10's. I was fortunate, because the mechanic who did the work gave me an even swap on the housings, since I was already such a good customer that week...

What's your plan for the new diff's? Are you planning on going L/S, or locking them?

As for the speedo, mine is 10% off. I just live with it. I find no value in knowing how fast I'm really going...