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Discussion Starter · #1 · (Edited)
After putting 2500 miles on the EB I've been able to get accustomed to the truck pretty well.

One trait I've noticed is that while decelerating at most any speed, then commanding acceleration the transmission will then command a downshift only after the accelerator is applied, this causes an substantial delay in the actual commanded acceleration. The perception is that there's a disconnected feeling from the command of the driver to when the truck will actually accelerate.

Examples of symptom:

#1 When decelerating in a residential area to take a 90 degree corner, 20 miles an hour slowing to 6 miles an hour or so. The truck is in 3rd just before starting turn in to the corner, completely off the gas, coasting through the corner, as the steering wheel comes back to center on corner exit,the truck is still in 3rd, start to pick up the gas, it will then delay, downshift to 2nd, then accelerate out. The result being noticeable delay, from the command of acceleration, to actual acceleration as the transmission makes a decision to downshift.

#2 Slowing down coming toward a stop sign or light. I've noticed it will hold 3rd until right about 5 mph then shift to first just before the actual stop. If you don't come to absolute stop, the transmission will upon picking back up the accelerator, delay, shift from 3rd to 2nd, then actually accelerate. There's a noticeable delay.

To me it would make more sense if the truck when making decisions to downshift would consider, if acceleration was called for at this very instant, what gear should I be in, instead of making a decision for gear selection only when acceleration is commanded.

This symptom is very consistent, almost every time when decelerating then picking back up the throttle, it will pause, downshift then pick up acceleration. Almost it has to think about what commands to send to the transmission to select a gear. Almost like it ignores speed and gear selection until the accelerator is picked back up.

Anyone sense similar symptoms?
 

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Discussion Starter · #3 ·
Anyone notice similar experiences?

Everyone completely happy with the transmission programming?

I know I was spoiled coming from my last truck with impeccable transmission programming. I'm attempting to get used to the differences in which this truck makes decisions and executes them.
 

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A tune can help with what you're looking for in shift strategy.
 

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After putting 2500 miles on the EB I've been able to get accustomed to the truck pretty well.

One trait I've noticed is that while decelerating at most any speed, then commanding acceleration the transmission will then command a downshift only after the accelerator is applied, this causes an substantial delay in the actual commanded acceleration. The perception is that there's a disconnected feeling from the command of the driver to when the truck will actually accelerate.

Examples of symptom:

#1 When decelerating in a residential area to take a 90 degree corner, 20 miles an hour slowing to 6 miles an hour or so. The truck is in 3rd just before starting turn in to the corner, completely off the gas, coasting through the corner, as the steering wheel comes back to center on corner exit,the truck is still in 3rd, start to pick up the gas, it will then delay, downshift to 2nd, then accelerate out. The result being noticeable delay, from the command of acceleration, to actual acceleration as the transmission makes a decision to downshift.

#2 Slowing down coming toward a stop sign or light. I've noticed it will hold 3rd until right about 5 mph then shift to first just before the actual stop. If you don't come to absolute stop, the transmission will upon picking back up the accelerator, delay, shift from 3rd to 2nd, then actually accelerate. There's a noticeable delay.

To me it would make more sense if the truck when making decisions to downshift would consider, if acceleration was called for at this very instant, what gear should I be in, instead of making a decision for gear selection only when acceleration is commanded.

This symptom is very consistent, almost every time when decelerating then picking back up the throttle, it will pause, downshift then pick up acceleration. Almost it has to think about what commands to send to the transmission to select a gear. Almost like it ignores speed and gear selection until the accelerator is picked back up.

Anyone sense similar symptoms?
I have noticed the same thing. I assumed it was related to turbo lag. When it does shift down and the turbo spins up it's sometime too much power for the conditions. This is my first turbo and I assumed the situation is normal for turbo equipped vehicles....
 

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Discussion Starter · #6 ·
I have noticed the same thing. I assumed it was related to turbo lag. When it does shift down and the turbo spins up it's sometime too much power for the conditions. This is my first turbo and I assumed the situation is normal for turbo equipped vehicles....
My last truck was turbo charged, the OEM programming on it was better.

I've experienced this as well. I believe this is a byproduct of commanding throttle and the driver not getting the expected response. The driver keeps pressing, when it finally executes the downshift and applies power, there's more power than what was originally desired.

I'm likely going to try a transmission tune from the aftermarket to see if they can nail down the tune to be in synchronous harmony with the driver.

I had a Diablo programmer on my last truck. I worked with a gentlemen at Diablo on my tune, and they absolutely nailed it. It had better shifting characteristics than my previous G8 GT.
 

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Discussion Starter · #8 · (Edited)
Has there been a vehicle made in the last 10 years that doesn't have an electronically actuated throttle body? Every vehicle I've owned in the last decade has had an electronically actuated throttle. Just seems like something is overlooked with the EB application in our trucks. When slowing to a stop instead of downshifting from 3rd to 1st gear at 3mph right before the stop, why not select 2nd gear at 10 mph in the chance to be prepared if the throttle is picked back up, the truck is in the correct gear thus eliminating delay. I'm guessing it has something to do with fuel economy. Every little bit counts these days.

Various manufacturers have even gone as far to implement Deceleration Fuel Cut Off (DFCO) on various applications over the years. Implemented many different ways, some cutting fuel off from select cylinders following an odd sequence in the firing order, and some cutting off fuel all together.

Selecting tow haul mode in the truck resolves the delay somewhat, though the byproduct is unnecessary holding of RPM's for the driving situation. That's expected and overkill attempting to change the experience of the deceleration transmission gear selection points.

In summary it simply doesn't feel correct when it occurs. Doesn't matter if it's this truck, another truck, another vehicle. It's just an odd behavior.
 

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I learned with my first EB that there's a big disconnect between throttle input and the engine's reaction. First time in the snow, I wanted to blip the throttle to slide the rear end around just a little bit, I blipped, the truck slid and kept the,power on till almost 2 full seconds after letting off the gas. Very disconcerting.
To make sure,it wasn't a fluke, I tried it again a couple times and same trick each time. No more playing in the snow with this thing.
 

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Discussion Starter · #10 ·
Thanks for your input medik418. It's valuable to here other owners have experienced this and that the symptom isn't isolated.
 

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Discussion Starter · #12 ·
Here's the scenario in which is the source of the issue.


The symptom specifically is the downshifting from third to first while decelerating from 23 mph to around 3 mph. The truck maintains third gear until just before coming to a complete stop when it downshifts and gives the driver first. Second is never an option while in deceleration.


This is where the symptom is located between 23 mph and 3 mph in third. If your decelerating and decide to pick back up the throttle at 15 mph, third gear is sufficient. If your decelerating and decide to pick back up the throttle at 7mph, third gear isn't sufficient as the truck hesitates, makes a decision to shift to second then starts to accelerate. This later scenario seems like an eternity. In reality it's likely 1.5 to 2.5 seconds between the time the driver commands throttle and the truck actually performs acceleration. Depending on the driving situation the delay can be unnerving, trying to merge or blend into traffic.

Picked up an SCT programmer with custom tunes. The SCT standard tunes won't install as the strategy code or PCM version is newer than what SCT currently supports. The custom tunes from the dealer were the only option at this time. Installed a transmission only tune. The symptom didn't change. Installed an 87 mild tow and performance tune. Symptom didn't change. Corresponded with the tuner dealer, I now understand from the dealer the custom tunes don't change this portion of the shift deceleration schedule. It was stated that if second gear is engaged on deceleration the transmission bangs into second gear which isn't desirable. I'd like more evidence before its 2nd gear is scientifically proven it can't be engaged on deceleration.

Any customers of tunes have any experience and can verify a tune that modifies the deceleration shift schedule behavior?

I haven't tried engaging tow haul to see how this might effect the deceleration shift schedule. I might try that tomorrow just to validate if the OEM Ford tow/haul shift schedule changes this behavior.
 

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Discussion Starter · #13 ·
Got an email back from my tune dealer that stated engaging 2nd gear on declaration will bang into second hard. I thought that was interesting as when I engage tow haul it engages 2nd gear on deceleration and it doesn't bang.

Any tunes out there proven to engage 2 gear on deceleration?
 

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I noticed the same thing, only you describe it a lot better then I did when I brought it in.
Dealer said it was normal. The computer is just trying to maximize fuel efficiency.
 

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I drive in tow/haul almost exclusively. Works great!
The trans has learned what I need from it and has adapted very well.
Patience.
 

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Discussion Starter · #16 ·
Looking for more of a permanent solution that doesn't need the tow haul button pushed every time the truck is started. Additionally I don't need the mileage penalty as mine is only the low side, currently averaging 15.5 mpg.

Small ask, but it's not too much however to think someone worth their weight in programming salt can program the truck to engage 2nd gear on deceleration. Surely someone can do this. My current programmer dealer couldn't seem more disinterested. I'm sure someone in our free enterprise economy would like the opportunity and additional revenue. Now just got to find that person.
 

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My MPT tune will shift into second from third...sometimes it bangs slightly sometimes it's smooth...
Mike worked on my shift strategy for a different reason, but this was part of his revision for my truck... :D

Sent from my SCH-I545 using Tapatalk 2
 

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Discussion Starter · #18 ·
My MPT tune will shift into second from third...sometimes it bangs slightly sometimes it's smooth...
Mike worked on my shift strategy for a different reason, but this was part of his revision for my truck... :D
Did you mean third to second on deceleration?
 
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