Changing rear end gears

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Deadman

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mechanical advantage is still mechanical advantage. No matter how you swing it, its still an advantage.

Its no different than lifting a 100lbs next to your body vs 3 feet away at arms length.

Anything can compromise, like the transmission and such, but its always just that, a compromise......
 

Fozzy

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mechanical advantage is still mechanical advantage. No matter how you swing it, its still an advantage.

Its no different than lifting a 100lbs next to your body vs 3 feet away at arms length.

Anything can compromise, like the transmission and such, but its always just that, a compromise......

We are talking maybe 1” from your chest.


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lv2drive

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i love this.

not needing to tow anything heavy, i also love my 3.31, it pulls like a freight train to me especially considering the sheer size of the expy. (that’s coming from a diesel touareg that is a monster + only beats the expy by reliability + handling like a porsche - because it literally is.)

honestly i would probably get myself in trouble with the “advantage” of the 3.73 paired with this engine. i already catch myself exceeding the speed limit just a little too much, without even realizing it, on my daily jaunts to school where my kid reminds me now that she is old enough / tall enough to read the speedo from the rear now. . :-/

i would absolutely not even dream of messing with the internal gears, too much of a PITA + variables, for not nearly enough “advantage” in return.
 

sjwhiteley

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Maybe if we are towing 100K. The 10 Speed and gears can easily make up the difference and handle the weight the Expy can tow safely. Look at all of us with oversized tires. We can’t tow now that we changed our final drive ratio? It’s about the engine and transmission cooling.


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R.e. Engine/cooling: Wouldn’t that imply that both the vehicles can tow the max rating? (Changing the radiator out to the HD one).

And you are correct that putting oversized tires will theoretically decrease your max rating (assuming the max rating is actually a max).

I am aware that there are numerous reports of the engine/cooling struggling at high loads: perhaps that’s truly the limiting factor and not the drivetrain.
 

shane_th_ee

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my kid reminds me now that she is old enough / tall enough to read the speedo from the rear now.
OT alert!
Mine, too. One of my favorite design elements of our old Jag was really deep set gauges. So only the driver could see the speedometer...
 

ShannonD

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I'm in a similar situation; didn't do enough research before purchasing and will be towing right at max non HD towing. In my humble opinion, I would start with a radiator and cooling upgrade for more bang for your buck. Gears are gonna absolutely make a big difference, but you're talking a lot of dough to change it out. Just don't know if it'd be worth it; can't just change out the rear gears and call it done. I personally believe these are way underrated for towing from factory, and I think cooling will be the issue before anything. Saying that, I'm not the one who has to honor your warranty if you were to ever have problems. I'll soon be upgrading my radiator and adding another auxiliary transmission cooler just as a good buffer.
 

Fozzy

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Here is something for you “ gotta have the 3:73’s to tow guys” to think about.
Looking at the 2021 build your own. The 3:73’s are not part of the HD tow package. But part of the eSLD package.
[emoji848]
a44230b87a2724a558b3ccb16a9cf2a7.jpg

31165fd0214047aabdb235cfad8e2a49.jpg


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Deadman

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You can thank the EPA for that. I'm sure they need to bump up their fleet mpg to meet some BS standard.
 

wakeboarder

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Here is something for you “ gotta have the 3:73’s to tow guys” to think about.
Looking at the 2021 build your own. The 3:73’s are not part of the HD tow package. But part of the eSLD package.
[emoji848]
a44230b87a2724a558b3ccb16a9cf2a7.jpg

31165fd0214047aabdb235cfad8e2a49.jpg


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According to the 2021 towing guide, the 3.73 gears are required to get greater than 6300 lbs towing. Some 3.73’s only have 6,000 lbs of towing capacity.

BE5D2A39-0927-4A35-B983-B3DBAFFAD096.jpeg
 

Fozzy

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According to the 2021 towing guide, the 3.73 gears are required to get greater than 6300 lbs towing. Some 3.73’s only have 6,000 lbs of towing capacity.

View attachment 42356

That’s the same chart for the 18-20’s as well. In 2021 they split the eSLD out of the package but this chart and brochure still reference the HD tow package including the eSLD. Window stickers are all over the place. Some have the HD tow and no charge for eSLD. Some have the tow and eSLD no charge and some charge for both. I would be pissed if I ordered the HD tow and later was told I need the 3:73’s. Or could just order the HD tow and save $1100.00 and get the eSLD for free. But if the 3:73’s are limited to 6K on some models it means the radiator is the bigger advantage like I have been saying all along.
Check out another great example of how easy Ford makes it to shop.

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