3.73 vs 4.11 in a 2008 E350 V10

I have owned a 99 v10 w/3.73s and 285/75-16 tires. For the last 15 years an 04 v10 w/4.10s w/285s also. I don't tow, both 4x4 EBs at around 9600#. Day and night difference. Hated the 3.73s, no power and constant downshifting. The driveability of the 4.10s is perfect I would not have it any other way. I think the mileage was about the same, but even if it wasn't the pleasure was worth it.
 
V10 tuning vs gearing

IMHO you're fine with 3.73s if you just uncork the V10 and let it breathe, the stock exhaust is VERY restrictive and requires a few modifications starting with the Y-pipe which resembles more of a T then a Y. I redesigned mine using SLP 200cpi catalytic converters, eliminated the T and used a Merge Collector from Vibrant Performance, then i used a Flowmaster 50 Series SUV Muffler, next up was an SCT X4 programmer and 87 octane tune from 5 star.
The butt dyno feels like i swapped out the V10 for a V12 and it runs like a scalded dog.
You can swap out your gears and spend the same amount of money (probably more) and you won't be nearly as satisfied with the end result, you'll still have a dog for an engine and you might have some gear whine if they aren't installed correctly.
Other mods include a 170 degree thermostat, Wix 46418 air filter and D.U.I. SOS coils ($370), keep in mind my V10 is a 2008 model and it's also a Jasper reman.
The engine runs cooler, makes a LOT more power and if i keep my foot out of it, gets better mileage. My goal when building the engine was not to make more power, my goal was to reduce operating temps, increase BMEP, fuel mileage, volumetric efficiency and engine longevity, the side effect was more power.
There's always more then one way to skin a cat, this was my choice, do it like you want too..
This forum doesn't allow me to add pics in normal fashion but if you want pics send me a PM and i will give you my email.. :b5:

PM sent with my email and cell.
 
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You can swap out your gears and spend the same amount of money (probably more) and you won't be nearly as satisfied with the end result, you'll still have a dog for an engine.

If you haven't done it, howe would you know?

FWIW - I did my intake, full exhaust, and tuning before doing lower gears. The lower gears matter most when towing. More power is great, but allowing the motor to spin at an RPM when the power is usable, matters more.
 
As carringb mentions above, you want to keep rpm's where its most usable. When you modify exhaust, you typically lose bottom end torque but gain it in higher rpms. If you keep 3.73's and run taller tires, you wont be in the rpm band where your motor makes the power.
 
I gotta admit this is one of the best post I've seen on here for the very desireable V10. I think there is a good middle ground here. I think making an engine breathe is key to a happy long life and horse power otherwise all the Veteran engine builders would not have ported and enlarged exhaust. I also believe it is not a race to the finish type of scenario for a VAN. I think that a nice exhaust upgrade with all Jorge says would be good "BUT" I agree with Caringb and mikracer I would drop in 4.30's with at least 4.10 on 285's for the engine sweet spot and not to mention the life of your TRANSMISSION which no one has spoken about yet! Also listen to Caringb about the Sterling rear axle with an E locker. I just spent roughly $500.00 on 4.30's with a rebuild kit and another $120.00 on TracLoc clutches for my Dana 60 rear! I wanted a Detroit but they are not available for my ridiculous semi float which I screwed up when I ordered the van. After thinking about it I would have been better off with a Sterling and the E locker at about $600.00 to $800.00 (low baller cash) with the 4.30's in it! By the way I run the 4.30's with a 7.3 diesel and my trans is happy when I mash it on my second level Bully Dog setting! It use to surge, NO more.
 
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I had mine done by agile and with 33's they recommend going to 4.10. it's not that 3.73 won't work but it will put more load on the trany. Over time you will wear on the trany and cause problems. While you have the did apart might as well put lockers or a limited slip.
 
Full floater go locker semi go Trac loc. Remember if your at 285's minimum 4.10 preferably 4.30. 35's 4.30 preferably 4.56 for the tranny sake!
 
A little late here (not around much)...
I have the V-10 in my 2010. Weighs about 8400 lbs. Not an ideal motor IMO. I call it a circle track motor because you have to rev it out like a race motor. Torque is at about 3500 rpm's which is ridiculous for a big block.
I started with 4.10's in my van on 285/70-17 (about 32.8"). Did ok but 4.56 would of been better.
I now have 295/70-17 (about 33.3"). 4.10's would downshift on a flat freeway going over an overpass. Yuk Out of its ideal power zone.
Went to 4.56 gears. Much better, but I feel 4.88's would be better. As we know the V-10 wants to spin. And you will never get any sort of mpg's with a V-10, it just ain't going to happen. I've towed a 4500 lb dry travel trailer. Now, big flatbed & enclosed trailers weighing 2700 empty & about 6500 loaded (so apprx 14,500 combined weight).
I am turning about 2250 rpms approaching 70 mph. I think I should turn more like 2500 at that speed. Its not going to hurt your mpg's because your mpg's will always suck. Over gear on ratio if you tow a lot IMO.
My rig has a intake, aftermarket muffler and a 5 star tune. The 5 Star tune did give me more power. We (5 Star) have estimated maybe a 75 HP gain. But it hurt mpg's. I used to be able to get 10-11 mpg's sometimes lol, but with the 5 Star tune its 8-10 mpg. Yes shift points are better (a whole nother story).
So... build up your V-10 for power. Forget about mpg's.
Or find a diesel Econoline. A 6.0 diesel will out power my V-10 anytime.

Oh, I bought a Duramax diesel Chevy truck for towing and it kicks butt. No need to tow anything sizable with the van anymore. Ahhh. Diesel power!:d8:
 
A little late here (not around much)...
I have the V-10 in my 2010. Weighs about 8400 lbs. Not an ideal motor IMO. I call it a circle track motor because you have to rev it out like a race motor. Torque is at about 3500 rpm's which is ridiculous for a big block.
I started with 4.10's in my van on 285/70-17 (about 32.8"). Did ok but 4.56 would of been better.
I now have 295/70-17 (about 33.3"). 4.10's would downshift on a flat freeway going over an overpass. Yuk Out of its ideal power zone.
Went to 4.56 gears. Much better, but I feel 4.88's would be better. As we know the V-10 wants to spin. And you will never get any sort of mpg's with a V-10, it just ain't going to happen. I've towed a 4500 lb dry travel trailer. Now, big flatbed & enclosed trailers weighing 2700 empty & about 6500 loaded (so apprx 14,500 combined weight).
I am turning about 2250 rpms approaching 70 mph. I think I should turn more like 2500 at that speed. Its not going to hurt your mpg's because your mpg's will always suck. Over gear on ratio if you tow a lot IMO.
My rig has a intake, aftermarket muffler and a 5 star tune. The 5 Star tune did give me more power. We (5 Star) have estimated maybe a 75 HP gain. But it hurt mpg's. I used to be able to get 10-11 mpg's sometimes lol, but with the 5 Star tune its 8-10 mpg. Yes shift points are better (a whole nother story).
So... build up your V-10 for power. Forget about mpg's.
Or find a diesel Econoline. A 6.0 diesel will out power my V-10 anytime.

Oh, I bought a Duramax diesel Chevy truck for towing and it kicks butt. No need to tow anything sizable with the van anymore. Ahhh. Diesel power!:d8:

My findings exactly. But the 4.56 gears are fine with my V-10 because my tires are not as tall. The only thing that engine has going for it is longevity.

I've had Cummins-powered trucks for years and love the low-rpm pulling power and fuel mileage. Gave serious consideration to having a Cummins conversion done to my van but ultimately, because of the rough and remote terrain I drive it in, gave up the idea. All that extra weight over the front axle would not be good...and the combination probably wouldn't be as rock-solid dependable as my current V-10 and Torqshift. So I carry extra gas and call it good.

I wish Ford had a V-8 Ecoboost equivalent - low end torque like a diesel without all the weight and complications.
 
Having owned a 03. V10 15 pass Stock roof w QuadVan's 4x4 TTB, 265's and 3.73's - No engine mods or tuner, light interior buildout, roof rack/basket, side ladder, stock bumpers. The lift was maybe 1.5" over stock:

13 years and 50k+ miles of driving / very little towing - I was VERY happy w that setup. Fwy mpg normally around 13.5 at 65 +/- mph.

Removed the roof rack and bars for a run to Loveland 14.9mpg over the 1200 miles at 70mph. Had CCV install their hi top, drove back and got nearly the same 14.8mpg w 80mph stretches on 80 in the mix.

So the V10 can get decent fuel mileage. Always felt like I had hardly any foot on the go pedal, it was perfectly setup for our usage.

Of course, if towing often and 5k lbs, I would think it prudent to change to the 4:10 or 4.30. But I would miss the lower rpms when running unloaded/not towing.
 
I'm the current owner of the van 1Der mentioned. It now has a CCV high top, 285/75 KO2's on it and 3.73 gears. I just did a run from the Bay Area up to Seattle and back. I averaged 10.5mpg in the mountains and 14.5 on the flats. Overall mileage for the entire round trip was 12.7 and I wasn't shy with the gas.
I currently don't tow and I don't think I'll go to larger tires so right now I'm happy where I'm at. Perhaps later if I start towing a lot I would look at the 4.30's.
 
I put a 2011 f250 4.30 gear factory e locker in mine. Would do it again. Highly recommend.
 

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