OK - currently have the 2004 V-10 limited w/78K miles. Current gears are 3:73's. When spring swap was being done, guy notes a little 90 weight oil in the axle. At some point I'll have to replace axle seals. I occasionally pull a travel trailer (23 ft Airstream) that runs about 7K pounds. My question is would it be worthwhile to regear when doing the seals?? AND...for those that have done the gearing, what would you recommend? I see guys have done - 4:10's; 4:30's and our friend in germany has even done 4:56's. What is the consensus?

 

Yes absolutely! Just changed out from 3.73 to 4.30 a this past summer and made a huge difference pulling my boat as well as cruising on the highway. I am running 315's on my truck so that made a bigger difference for me, but for pulling it really does help and allowed me to pick up about 2mpg towing as well, actually kept my highway milease around the same but got another 1-2mpg average as well.

 

My opinion is that a V10 and 4.30 with original size tires (i.e. 265/75/16) make a perfect combo for pulling.

Although if you are in a relatively flat area...the 3.73's work well too by simply locking out OD and running in 3rd...that does very well too...unless you plan to head to some serious grades that is...then the 3.73's just don't have the stuff to keep the V10 in the proper RPM range for power and that's where the 4.30's and the added 300 RPM's make a HUGE difference.

If you plan to keep stock tires...4.30's is a great choice...don't waste your time with 4.10's (IMO).

If you plan to go with larger diameter tires...depending on what size...you may want to look at 4.56's or possibly even 4.88's if you are going really big on the tires...

The key is to keep the final ratio after tires are factored in as close to 4.30's as possible if you plan to pull...

here is a tire diameter calculator that we have on FTE for your use. Automotive Calculators offer to you by Ford Trucks Enthusiasts | www.ford-trucks.com

Good luck,
Joe.

 

We are looking at a truck right now for our business that has 4:10's and we would like to change it to 3:73's so we may be willing to trade someone ring and pinions.

 

I need to subscribe to this thread... I'm trying to figure out how to get my Excursion to do better than 6MPG when I'm towing my 26' TT... I have the 3.73 gears and my tires are 315's...

 

I changed from 3.73 to 4.30 with my Excursion and 315's towing my boat and went from 5-6 to 7-8 mpg. For towing I would even look at doing 4.56 and even do better I believe. My towing and average MPG increased but suprisingly my highway MPG stayed about the same. But the truck is much nicer to drive and stays in O/D on the road much better.

 

Ok - this is getting interesting. This week I spoke with a local shop allegedly experienced in this and mentioned the 4:30's. He started looking some stuff up and stated that the aftermarket didn't produce 4:30's for the Excursion and I'd have to order them from Ford which would significantly increase the cost. He mentioned that we could go to 4:56 and it wouldn't be that big a jump from 4:30's (which seems accurate). But I'm just not sure about the statement about the availability of 4:30's. How did ya'll get your gears and what was the price?? He quoted me almost 1300 bucks just in labor before we even go tto the parts.

 

I bought another rear end with less mileage from a parts dealer and it included a limited slip as well while my original rear end was open. Ended up paying $650 for it I believe.
I looked at a gear swap before and easily found plenty of 4.30 sets but changing would run about $1100-1200.
After swapping I believe if I was changing gears out I would probably just go with the 4.56 rear end for some extra pulling but the 4.30 is a dramatic change in driving over the 3.73.

 

I have a friend that owns a small 4x4 fab shop and another really good friend does a lot of work with and or for him. So assuming I can get my install done fairly cheap... But Eric (owner of said shop) brought up an interesting point. What about the 5.13's... I mean, I'm already lifted on a (close enough) 35" tire, and yes someday I might even look at the 37" tire. Has anyone gone that low yet?

 

Yeah - I've got the 4X4 so it looks to be getting expensive. I've seen costs stated here on the forum for about 1,500 bucks to do both axles. I don't see how that is possible. Looking at about 1200 bucks for the gears (both sets) and another 1200 bucks for the labor?? How do folks do this for 1500??

I'm an Army dude so it isn't like uncle sugar has me rolling in cash.

 

In the research I did on gearing for Excursions, it seems the popular consensus for the V10's is 4.56 for 35in tires and 4.88 for 37in. especially if you are going to do any towing at all.

 

Local power train shop did my other vehicle for about $800 per axle, parts and labor. They also quoted me $2,200 to regear the Excursion AND add a LS locker in the rear.

 

3 this 4 that wow u all made my head hurt lol... so which would be good for no towing and lower RPMs

 

4.30 seems to be the best all around gearing for V10 excursions, but if you are running stock tires and not towing then your 3.73's will probably work the best.

 

From the research that I've done the popular consensus for towing any kind of real weight with the V-10 is to have the effective gear ratio somewhere right about 4.30. The effective gear ratio calculator I use is this one http://www.4lo.com/calc/geartire.php. The stock EX tire size is 31.5", using that and plugging in some other common tire sizes and available gear ratios you will find that bumping up to 35" tires and 4.88 gear will net an effective gear ratio of 4.39. Plugging in 37" tires and 5.13 gears will bring the effective gear ratio to 4.37.
The ratios and tire sizes in the quoted post come out to 35" with 4.56 = 4.10 and 37" with 4.88 = 4.18, both a little shy of the "ideal" towing effective ratio of 4.30.
I bought a set of complete axles with 4.88 gears and a rear locker for $1300 and plan to swap them under my EX once I get around to buying a set of Nitto 305/70R18E (35") Dura Grapplers. The goal of the project is to fill up my wheelwells some and get better performance when towing our 9-11k ToyHauler. Currently I am running 3.73 with 32"s and it downshifts when I run over a shadow, I'm looking forward to getting this swap done.