elptxjc

Picked up a brand new Platinum Screw EB 5.5' with max towing, FX4, and twin-panel MR in platinum white. It was right off the truck, so fortunately no freaking fuel system recall. Was a bit disappointed about the fuel consumption (16.2 MPG), but it was very windy on the way back, and I think dealer put crap gas on the truck (they have their own pumps). When I refueled, it felt a lot more powerful, and got 20 MPG, at the same 80-90, and even topped it off (effortlessly) at 103, when the speed limiter kicks in. Felt dead stable, so very happy with the combination of FX4 and max towing. At any rate, the main reason for my thread is this: While playing with the max gear selector on the shift lever on an uphill, noticed the following, and want the opinion from the experts which is the best method to deal with this for maximum engine longevity. Was going the speed limit (80) on cruises control (for accuracy) in SPORT mode, with just me inside. Here are my obvervations other than the instant fuel economy bar gauge basically didn't move among the 3 options below:

1. Tranny in 10th gear, rpm about 1,850, and boost about 1/2 gauge
2. Tranny in 9th gear, rpm about 2,200, and boost about 1/4 gauge
3. Tranny in 8th gear, rpm about 2,700, and boost about 0.

And here's the $64,000 question (Remember that one? Ha ha. Showing my age here). WHICH IS BETTER FOR THE ENGINE? My guess is #3 for both towing and not towing, but curious about the expert opinions here. As I mentioned, fuel economy is basically the same. I tried to look for specific engine details, like connecting rod length (the longer, the less angle/pressure on the cylinder walls at lower rpm), crankshaft dimensions, piston skirt length, etc., but nothing. Just that it has 10.5 compression ratio (which seems high for regular gas, by the way). I feel like anything below 2K rpm on a gas engine is lugging it, but maybe I'm wrong. Typically the higher the rpm the more the engine wears, but that typically applies to higher than 2/3s of the rev band, not 1/2, but we'll find out what's the consensus shortly. He he.

Finally, my observations. The tranny is not the most sophisticated one I've owned, but guess not that bad. Just want to make sure it's behaving 'normally'. The 1-2 shift when accelerating very easily is quite harsh. Some downshifts (again, in sport mode) when slowing down also feel quite abrupt, but they feel unrefined, rather than troublesome. It's also a big laggy to downshift when prodding the gas pedal, but not out of the ordinary, I guess. And since I can't drive it in manual mode with paddles, I just use the gear limitator on the highway to avoid lugging the engine, but it's nice to have a manual mode in case it's needed. I also hear what I think is the transfer case gear whine while idling, hot or cold; is this normal? My friends told me to change the rear shocks with Bilsteins (5100, I think) to improve ride quality, but honestly, I don't think they'd fix anything. The ride was surprisingly good given my expectations of live-axle and leaf springs, but when hitting a pot hole on just one side, the shudder is not pleasant at all. Can rear shocks fix that? I think the FX4 shocks are as good as it's going to get as far as an unloaded truck (which will be most of my driving), but comments welcome. The beefier front sway bar of the max towing package made the front just about as good as it can get on a truck. MUCH better than the air-spring equipped new Ram, which felt like an old Buick. Can't imagine how it feels at the ton; no thank you. Very impressed with the stability and surefootedness of this F-150. The hardest thing to get used to is being the steering wheel, which is HUGE, and having FOUR turns lock to lock, rather than 2 on the Audi, but after 600 miles, I'm getting used to it. The B&O is excellent, and so is the cabin noise levels, even at 90. Almost as quiet as the Audi with double-pane windows. Impressive on a freaking 4x4 truck. Very happy with the purchase. Thanks gang for all your help during my buying process. This place rocks .

Ssls6

I think your question is.....what causes less wear?

higher rpm with lower cylinder pressure

or

lower rpm with higher cylinder pressure

50 years ago it was normal to cruise at 3-3.5k rpm. Engines would get pretty tired after 100k-150k miles. I guess I would let Ford manage it and not lock out gears if the truck is empty. If your towing then lock out gears. Jack rabbit starts/stops likely stress things more than either case you are considering. Keep up with your maintenance and drive like a normal person.

StonedFX4

At 80 mph, I would have it in "normal" mode or "eco" mode and roll. The power band on mine seems to start around 1500 rpm, so I try to stay above 1500 rpms, helps with the mpg's as well.

moparado

Far as the tranny observations, Sport mode keeps each gear linger a lot more than normal mode at least in my 6 speed.
Sport mode could be one reason for the harsher downshifts and worse gas mileage.
Those are the main reasons i seldom use Sport mode.

The other reason for the harsh downshifts could be the tranny hasn't learned your driving habits yet. Give it some time.

mobandit

As to the harsh shifting, remember that the drive-train "learns" your driving habits over the first few hundred miles. Let it settle in after about 1k miles and see if it is still harsh...just my 2 cents...

CIPHER

^ This. make sure you lock out gears. The sweet spot of the torque band is 1800-2500rpm's . Try to stay in there.

Also, these trucks are tuned for optimum gas usage at 70 miles per hour to meet regulations. Anything over that or using Sport mode or towing in the wind will cause your efficiency to drop. Don't worry about it too much unless there a significant change.

Napalm

Direct toward your question - the computer is going to want to be in condition 1 when you are empty and it can hack it. IE 10th gear, lower rpms - whatever boost. and I say it that way on purpose. boost within the margins doesn't hurt the engine made for it from moment one. So from the piston wrist pins, to the connecting rods, to the bearings to the turbo's - it really doesn't care as that's what it was made for. Note however as you put weight in the truck or you end up towing - don't be so surprised if you see it move to condition 2 or 3. where it will stay out of 10th, and increase the RPM's. This is good for the crank bearings under higher loads. By that I mean torque loads - from the drivetrain pushing against the engine.

1800 RPM while underboost is not lugging this engine. 1400 rpm with no boost is probably lugging the engine some but you will probably never be in that condition. ONe of the advantages of the 10sp - there's enough gear options to keep the RPM's in a happy place - and vary the boost accordingly.

Comments on the transmission - if your dealer didn't prep the truck right it probably still has some of the learned behavior from the various test drives it was taken on. Which will change a bit over time. But it does want to do what you ask of it - once it figures out your pattern. Some things you might wonder about. Yes it skips gears - ON purpose. In fact depending on your rear gear ratio it's possible there's a gear in there you might rarely if ever use. Don't be surprised as it might well start off in 2nd or even 3rd with a gentle start. On the opposite spectrum - in sport mode don't be surprised if you gun it while at 60, that it will drop from 8th to 4th in a blink. There are no syncros in the transmission and all gear changes or well most are the swapping of a gear set and clutch set. The torque converter will stay locked up most of the time. Cold temp jerkiness is an unfortunate side effect and it's not just an issue on the ford version.

elptxjc

Thanks a lot for that great explanation. I was a bit confused by this engine, since my previous and present turbo engines produce peak torque below 2K rpm. This one is listed at 3,500 (470 ft/lbs), which is quite high. Therefore, I thought it was going to be happier at least above 2K rpm. My other thinking was at 80 to 90 mph, this thing is a brick, and it probably resembles towing a trailer at 60 mph due to the insane drag it must produce at this speed, coupled to the fact the bed is still not covered, adding to the drag (like a parachute). Good to know about the tranny behavior. I noticed my poor engine had TWO freaking hours of idle when I first started it (just 13 miles on the clock). Don't know if that affects tranny behavior, but glad to know it takes time to learn you behavior. I'll probably drive in sport mode all the time. On normal mode, it seems to be too laggy, and downshifts to almost idle. Coming from sports cars, rather pay a little bit more at the pump but have a more responsive tranny. He he.

Hey folks, one last question. I read somewhere to use premium gas when towing, but didn't find anything in the manual. Is that the case? Thx.

acdii

The best FE for the engine is 1500 or less. My 14 with 6 speed had 3.15 gears so cruising at 60 it ran at 1400 RPM, but go to pass someone and it took off like a bat out of hell, and it got the best MPG of all my trucks with 20-24 MPG. My 16 with 3.55 gears gets 17-18 MPG, RPM is 1600 or so, and passing sucks. With a brand new truck it is best to vary speeds and not joy ride it for at least 500 miles so that the PCM can learn properly and be at it's most efficient. If you play with all the modes that only sets it back in it's learning and if done enough can actually be detrimental to proper learning and can result in poor shifting and poor fuel efficiency.

Best method I found for the first 1000 miles is to be very conservative with it, and it will treat you back with good performance and good FE.

Aj06bolt12r

My .02. If not towing, option 1 2 or 3 will make no difference in engine longevity. Its perfectly happy in either condition.

When towing I would lock out 9th and 10th for the reasons stated above and to spread the load that the engine is seeing out over more " power strokes ". It will also help the engine to stay cooler and prevent unnecessary shifting.

I run 93 octane in my 3.5 at all times. It allows the PCM to run optimal ignition timing which results in a more efficient and powerful engine. I read a study once where they were trying to prove if 93 octane had any benefit on modern stock engine vehicles. They tested several makes and models on a chassis dyno trying to recreate many different real world scenarios. City driving, towing ect. On some lower performance naturally aspirated engines 93 actually made less power and had worse fuel economy. But on the ecoboost engine there were gains across the board in power and fuel economy.