2018 Expedition Gearing Option Decision

[Ryan Jones]

Looking to pull the trigger on a 2018 Expedition 4x4 limited and having difficult time deciding between 3.31 non-limited slip and the 3.73 Electronic Limited Slip.

This will be replacing a 2011 F150 4x4 Off road and will be the main family hauler.

Driving Conditions:
Mix of city and highway driving 50/50
Lead foot and hit the highways around 80mph
regularly driving up to the Sierra's (tahoe area) during summer and winter with a pretty full load (4 adults, 1 kid and gear).
Some light offroad (fire trails, etc.)
Very little towing, but tow a 6,000lbs ski boat twice a year on flat highway.

I've only used the locking rear on my F150 4-5 times over the last 7 years and probably wasn't truly necessary, just a precaution.

My first instinct was to go to the 3.31 just to save on MPG due to my lead foot on the highway and keeping the RPM's down, but struggling with the decision and the limited slip with the 3.73.

I know I will miss the acceleration of the 3.73 off the line and while towing, but thinking the new 10 speed transmission would be fine.

any advice would be helpful.

-Ryan

 

[JExpedition07]

3.73

 

[dlcorbett]

Agreed. Get the tow pkg, youll recieve everything youll want and need and make your powertrain more durable for the lead footedness, which youll def have with this engine. Your mpg is pretty negligible, u thinkin about fe but having keeping your foot on the gas is an oxymoron lol. If you baby the engine, your mpg will be great regardless of drivetrain.

 

[edizzle]

yep

 

[Ryan Jones]

great feedback, thank you. I know having a lead foot and good MPG is an oxymoron... HA! I always say I'll be better and save gas, but it only lasts a couple days. We need goals, right?
Do the higher RPM's at FWY speeds prematurely wear out the engine or is the difference negligible?

 

[edizzle]

negligible. it may equal 200 rpm. i cant remember but i want to say 80 was hovering at 2000rpm

 

[shane_th_ee]

The 3.31 rear axle 4x4 max has a maximum towing capacity of 6000lbs with a GCWR of 12,400lbs. That’d be without anybody else besides the driver and no gear... You should get the FX4 or max trailer package. Personally, I’ve ordered one with both packages. As for durability, while you might get some savings from the lower RPMs with the 3.31, you’ll lose more due to the higher engine temps as the 3.73 comes with an upgraded radiator.

 

[mossback]

3.73 for sure. Especially if you’ll be doing any mountain driving.

 

[jgudnason]

Agreed, another vote for the 3.73

 

[brick]

Get the 3.73. You will want the limited slip for pulling your boat up the launch ramp.
brick

 

[Paddler]

I went with the 3.31 rear end, despite the fact that mine's a Max. My boat/motor trailer is 3800#. I'm sure the 3.31 will be fine for your needs, especially with the new 10 speed trans. Doubt you'll need limited slip to get your boat out.

 

[rjdelp7]

3.31=yawn, 3.73=smile.

 

[JimmyC]

HD Towing package with the 3.73 ratio, had it on my F-150 loved it

 

[Paddler]

Given the OP's intended use, the 3.73 isn't the best choice. If he only tows twice a year on flat ground, the 3.31 will be better for what he's doing.

 

[edizzle]

Given the OP's intended use, the 3.73 isn't the best choice. If he only tows twice a year on flat ground, the 3.31 will be better for what he's doing.

agreed, but one should also consider the "seat of the pants feel" LOL

 

[aggiegrad05]

Given the OP's intended use, the 3.73 isn't the best choice. If he only tows twice a year on flat ground, the 3.31 will be better for what he's doing.

This is why I went with the 3.31. I had the 3.73 on my F150 and didn't tow anything in 6 years of owning it. I would have liked the upgraded radiator given our hot Texas summers, but it just wasn't worth it for me to spend the extra cash for the max tow package. Sure the 3.73 has benefits, and if it was the same price for both and you could pick I'd have picked the 3.73, but $1500 is real money for something that's "nice to have" but wouldn't have any real benefit for me. If you're like the OP and I and don't tow anything...the 3.31 is a perfect choice.

 

[shane_th_ee]

This is why I went with the 3.31. I had the 3.73 on my F150 and didn't tow anything in 6 years of owning it. I would have liked the upgraded radiator given our hot Texas summers, but it just wasn't worth it for me to spend the extra cash for the max tow package. Sure the 3.73 has benefits, and if it was the same price for both and you could pick I'd have picked the 3.73, but $1500 is real money for something that's "nice to have" but wouldn't have any real benefit for me. If you're like the OP and I and don't tow anything...the 3.31 is a perfect choice.

But it's not just the rear-axle gearing. He's looking at a 6000lb vehicle, a 6000lb boat and a GCWR of 12,400lbs. 12,400-6,000-6,000 is 400lbs. 400lbs is not a lot of weight for people and stuff. The max trailer package or the FX4 package gives him an upgraded transmission and bumps up the GCWR to ~14,000lbs.
And he did said he'll be driving through central California (where it gets hot!) and the Sierras* (while not towing) at high speeds with a truck full of people and stuff. This is exactly where you'd want the upgraded radiator. The FX4 package would also give him some protection for his "light off-roading" so he doesn't accidentally puncture an oil pan or gas tank if he misjudges the size of a rock way up some forest service road. I'd say he gets better tires, but from all the photos I've seen it looks like everybody with 18" wheels gets the same highway all season Michelin Primacy tires...
*As in the Sierra Mountains. Those are mountains, real ones, with glaciers and such. In other words, not the mis-named hills they have on the East Coast.

 

[aggiegrad05]

But it's not just the rear-axle gearing. He's looking at a 6000lb vehicle, a 6000lb boat and a GCWR of 12,400lbs. 12,400-6,000-6,000 is 400lbs. 400lbs is not a lot of weight for people and stuff. The max trailer package or the FX4 package gives him an upgraded transmission and bumps up the GCWR to ~14,000lbs.
And he did said he'll be driving through central California (where it gets hot!) and the Sierras* (while not towing) at high speeds with a truck full of people and stuff. This is exactly where you'd want the upgraded radiator.
*As in the Sierra Mountains. Those are mountains, real ones, with glaciers and such. In other words, not the mis-named hills they have on the East Coast.

I don't disagree. My point was simply that you need to buy for what you will be doing. If you plan to tow anything even close to the limit of the vehicle (without the HD tow package), then you need the HD tow package. Buying a vehicle with a 6000# tow rating with plans to regularly (or even semi-regularly) tow 5000# and haul a bunch of people is a bad idea.

So I do think he needs the HD tow package for the weight and the environment in which he'll be hauling that weight (and I apologize if my post was confusing in that respect). But a lot of the posts on this thread made it sound as though everyone should upgrade to that package simply for the axle ratio and because MOAR POWA!!!!!...and that's just not the case.

The 3.31 is perfectly fine for a lot of us who just want to drive a large, roomy truck-based SUV in normal on-road and soft-road conditions. Tick boxes on your order form because you need them...not just because.

 

[rjdelp7]

GM put 4.10 gears in the 1980's S10 Blazers. They would rev too high in 1st gear, wouldn't go over 80mph and motors would self destruct on cue, at 105K.

 

[mossback]

GM put 4.10 gears in the 1980's S10 Blazers. They would rev too high in 1st gear, wouldn't go over 80mph and motors would self destruct on cue, at 105K.

It went beyond the 80's. I had the 4.11 ratio in my 99 Tahoe.