I have the 3.73's now, and I know swapping out to 4.10 would be better, but not enough of a change to make it worthwhile $$ wise. BUT...Would everything swap over from a 4.30 geared Excursion of the same year? I would LOVE to have the 4.30 gearing in my truck?

 

Anyone out there??

 

Jeff, I tried looking the specs up for you, but I'm having problems with the site.

Go here:

https://www.fleet.ford.com/truckbbas.../techspec.html

And look up the axle specs between an '02 Ex and '02 F250. For some reason the '03 Ex isn't available here, but the specs should be the same. I think it'll work just fine but I'm not sure of that.

If it comes down to it, get down there and measure them!

 

Should match up perfectly.

How are you going to get the speedo and shift points right, dealer reflash or tuner?

Tell us how it goes and what the MPGs do, I am wanting to do his swap on my V10 E350.

 

IF it ever happens I'm hoping my Diablo tuner will be of some help. Right now it's just a pipe dream...

 

When changing out just the gears, no speedo adjustment required. I went from 3.73 to 4.30 and speedo is perfect. I do use a SuperTuner to change shift points for towing, but it is not required. If the rearend from the Ex does match up, you'll be pleased with it. It really helps with the get up and go, but not much on the "sustained" towing (in other words, it'll still gear hunt on hills, just now quite as much).

 

The only thing you really have to watch out for is the way the brake brackets mount up. But in the same year it should be the same between the two trucks. Speed is read off the differential, not the transmission. The only time you have to recal the speedo is when you change tire size.

 

I knew the vss was on the diff, I just never knew you could change gears with out tuning.

I get how the speedo is ok, but how does the tranny change its shift points without the tuner?

Is shifting based on RPM instead of speed?