Looks like Motortrend has some info on the next Navigator/Expedition drivetrain:
Apparently, it's likely the Navigator will be V6 only, offering both the 3.7L V6 as a base engine and the 3.5L Ecoboost as a premium engine.
The Expedition will likely offer both V6's, as well as the 5.0L V8.
With that said, considering all the Navigator's competition is 400+hp, it wouldn't surprise me if the next generation Navigator gets a next generation Ecoboost with 400+hp. Either that, or they really are going to drop ~700lbs like they talked about.
I have not driven any of the new engines, but I know my 5.4 is by no means overpowered. I would also be concerned about where they are going to shed weight. I could not imagine the Expy of today (mine is 2011) with less horsepower and torque. I don't think my Expy is completely underpowered and it tows fine for how i use it (about 5500-6000lbs a few times a year), but I could not imagine less than what it has. My pops had one of the first Expys 4x4 and 4.6 - it was a sled. We also stuck with the Expy due to its weight - it just feels solid. I am certain Ford knows what they are doing and there is probably a market segment for the 3.7 liter motor - it just certainly is not me in its current form. But, hey, there are still guys that have the 4.6 running around. Now the 5.0 (which is what my next F150 will most likely have) - I am excited to see that. The 3.5 ecoboost has not grown on me yet - but I have bad experiences with turbos on as motors, so that is my hatchet to bury.
I honestly think the only reason they're offering the 3.7L is for livery and fleet duty. With the Crown Vic gone, a lot of livery companies have been buying Expeditions and Navigators. With the 3.7L they can keep the price down and the fuel economy rating up.
For the average buyer, the 5.0L and 3.5L Ecoboost are probably going to be the engines of choice.
Especially since it's all but confirmed that the 5.0L is eventually going to get direct injection, which should give it a healthy hp and tq bump. Which, again, I'm sure would lead to the Ecoboost getting a hp/tq bump as well if they want to keep that the premium offering.
I can not justify any reason why Ford would insert the 3.7 into it's high end luxury SUV Nav. It sees no commercial duty like the Expedition sometimes does.
I don't know where you live, but around the NY area, Navigators and Yukon Denalis are popular with livery companies. Every time I call for a car to the airport, one of them shows up, especially now that the Town Car is gone.
With that said, one does have to keep in mind that, if the 5.0l gets an update, the 3.7l could foreseeably get one as well. With direct injection it could see over 330hp and 290ft-lbs of tq like Hyundai gets from their direct injected 3.8l. That would be perfectly adequate for a base engine in the navi/expy, especially if both see a bit of a weight reduction.
I see few Navigators at the airports in the DC area, zero Tuesday on my flight out and zero yesterday on my return flight. Did see several Escalades and Denalis though.
Dropping the ~700 lbs that was mentioned in the article would put the new Expedition at or under the current Explorer. Not sure I'm buying that.
<300 ft/lbs in a vehicle that heavy and with that much frontal or surface area that has the GVW to haul 8 people and luggage (especially on the extended version) would be working too hard to provide better fuel ecomomy than the 5.0 or EB motors IMHO, but then again, it is available in the F150. It would be interesting to know what the fuel economy is on a half-loaded F150 with 3.7, 5.0, and EB.
Not sure what the true ratio is, but I would guess that the consumer -vs-commercial Expedition ratio is 95% / 5%, not sure I see the justification for a 3rd (3.7) powerplant. But then again, in 1969 you could select between 10 power plants in the Mustang, though I would only want 4 .
dose it really hurt to offer all 4 engines? talk about lazy........the Escalade get bad MPG yet it still over sales the navigator
There has been some rumor that they might drop the 6.2L from the next gen F150. Which, if that's the case, it offers a good explanation for why the Expedition/Navigator won't see it as an option either. That leaves the three remaining engine options; the 3.7L V6, the 5.0L V8, and the 3.5L V6TT.
Now, a while back, Ford was entertaining putting an even smaller Ecoboost in the F150. No talk of displacement, but on the Mustang front they're bringing out a 2.3L or 2.4L 4-cyl ecoboost making over 300hp. I see no reason that engine wouldn't be the smaller Ecoboost they were talking about. Especially if the next gen truck drops as much weight as is rumored (and the other engine options get a power bump).
It will definitely be interesting to see what the future brings. By 2016 CAFE says the F150 has to average about 23 mpg combined (up from the current 17). To get average fuel economy like that I could see a lot more small engines and a lot less V8's. Kinda like the replacement for the E-series (the full size Transit). It only offers a 3.7L V6, a 3.2L I5 Diesel, and a 3.5L Ecoboost V6 now. That's a big change from just a few years ago when they offered a V10 and three V8's.