I posted a question a little while ago about my transmission. Here is an update:
Basically I cruise in 6th gear at 50 mph with the engine right around 1,200 - 1,300 rpm's, and when I slightly press the gas pedal, just enough to NOT make it shift down into 5th, the engine rpm's suddenly increase to right around 2,000 rpm with nearly no speed increase. That's a jump of 700 - 800 rpm.
So today I went to a dealer and test drove another EB, and it did the exact same. I guess I am just not used to automatic transmissions yet, since this is my first vehicle with one.
When I try the same thing at 60 mph, btw, the truck almost immediately shifts down, it does not do the rpm increase thing, and the truck I tested today did the same there as well.
So what is it doing?


A funny thing on the side: the salesperson told me that I'd get 17 mph towing. Now that's not what I hear from others, even though I have not towed my TT yet. But 17 is what I get as NOT towing, on average.

 

Sounds like the torque converter unlocking to me. When it unlocks you can get wide range rpm changes with minimal speed changes due to the clutch's allowing it to slip. Different speeds and RPM's will behave differently as the available torque is different at those speeds. The unlock is likely computer controlled based one some weird available torque calculation.

 

There are so many different behavioral issues with these trucks that I've found to be the nature of the beast. My 2011 feels nothing like my 2004 Expy, in fact it feels like two different car manufacturers.

I really don't pay attention to any of my truck's quirks as I haven't had any issues, no loss of power and no drop in MPG's. If I see a leak or hearing something real foreign, then it's be time to call Houston. LOL.

I haven't really gotten into my truck for awhile as traffic around here is so unpredictable. But yesterday I had a chance to run her up to 90 while entering the freeway and OMG it still feels like a 200 mph wind pushing from behind as you go screaming down the highway.

 

Flixden, it was a downshift, I caught my truck doing the same thing on an on ramp from one freeway to another, 23s to 96e coming home from frankenmuth tonight, that ramp is a left exit that goes uphill and turns hard left, slowing down for the turn back on the gas the tach rises and I feel the downshift, but the gear display did not register it, followed by the upshift back at cruise speed, so the question is why the gear display did not register it?

 

I still say torque converter unlocking not a gear shift, especially if the gear display doesn't register it.

 

j.grif, it sounds like you are talking about the same thing, looking at the rpm's it seems like a downshift. The truck at the dealer did exactly the same thing. I can repeat it - every time. I agree with cgartly that it is the torque converter or something, and not actually a downshift. It does feel weird, kind of like partly depressing the clutch with a stick or something, it is just very controlled.
If somebody wants to try: go about 45 - 50 mph, not faster, on a flat road. Make sure you are barely on the gas, and are in 6th gear. Now very slowly step on it, until the rpm's go up without a gear shift. Repeat and go slower if it shifts.
Anybody willing to try and report back?

Thanks!

 

If you do some reading on how an automatic works, it will help understand the why of what the transmission is trying to do.

In the early 2 speed transmissions that only shifted once, the torque converter did not lock up at all, so you could really get a huge variation of rpms depending on the driving condition. That's why a manual transmission back then usually got better fuel mileage than an auto.

Then in the 80's to save fuel, the torque converter was designed to lock up. Usually when in 3rd or 4th gear at above 45 mph.

Now these new engines and transmissions are married together with the computer to get the best fuel mileage at any given situation, and to reduce emissions. It is also why the dealer has to do so many "flash's" of the ECM's to get rid of some of the complaints. It is pretty much impossible to program an engine to get you the best fuel mileage, lowest emissions, and best drivability for your type of driving. That is why custom "tuners" are better than off the shelf because the programer can "adjust" the ECM to the drivers style of driving and normal conditions.

Many of the questions regarding these new trucks is because Ford now provides all of the same information that "hot rodders" have been using for years. I have had a tach and vacuum gauge on every vehicle I have owned since my first car. When idiot lights appeared on vehicles, we all got mechanical gauges. Even now with the new engine controls, I have used a "Scanguage" to monitor my vehicle since the first one was produced.

Sometimes I think some of the issues that come out in these forums is just lack of knowledge regarding vehicles. But I also think is because the service writers at the dealers do not really understand what is going on either. When you talk to a really good automatic transmission tech, he is seeing in his mind how the transmission works, and "translating" the condition you are describing into how the transmission should be functioning. But how many times do we get to talk directly to the tech. Most times it is up to him to read the writers notes, and test drive, hoping he can duplicate the problem.

I think as we learn to live with these new systems, it will get better. But it's going to take time to educate the driver, service writer, and tech on the proper "language".

 

Yes, It is the torque converter clutch (TCC) unlocking, not the transmission downshifting, the TCC eliminates the slippage in the converter to improve mileage, the slippage you have when at a stop sign is "locked up" when the vehicle gets moving but they also unlock it when the truck needs the added torque multi-pucation the converter provides, it is normal operation and is in all makes of vehicles these days.

 

"speedsauto Yes, It is the torque converter clutch (TCC) unlocking, not the transmission downshifting, the TCC eliminates the slippage in the converter to improve mileage, the slippage you have when at a stop sign is "locked up" when the vehicle gets moving but they also unlock it when the truck needs the added torque multi-pucation the converter provides, it is normal operation and is in all makes of vehicles these days."

Yup, for sure thats what it is, I asked my service guy as well and he explained it just like on here...

 

Thanks everybody. Not a big deal at all, I'll get used to it in no time.
Bottom line is though that I am missing my manual transmission a little bit every day. What a shame that they stop making them in more and more cars and trucks. People get lazy, and then we miss all the fun because of it!
I am aware how the transmission works fairly well, I just didn't know that the TC unlocking could be so pronounced / noticeable that it almost feels like a downshift.
I do like the auto tranny when zipping my coffee in traffic, and will probably like it when backing the travel trailer, especially uphill and turning at the same time. So it is not all bad. Do we have an emoticon with one crying and one laughing eye?

 

Back in the day all I would have in my trucks was manuals. My first auto was in my 1988 F150 and I've had atos only since then. After getting used to the autos I wouldn't have anything else....especially now with all the advancements and the 6 speeeds. I really like this select shift in my new truck.

 

Technology has improved automatics to the point where the only reason for having a stickshift is the fun/novelty factor. Most vehicles with both transmission options give the same or better fuel economy with the automatic now, as opposed to 10+ years ago when there was a noticeable improvement by going with a manual. Aside from refinements in gearset, actuation and shift strategy, the lockup torque converter and progressive use thereof through the gears has probably given the biggest improvement in automatic transmission efficiency. It allows power delivery in a direct-drive mode exactly like a manual.

 

Besides fun, there is also cost, and maintenance. A manual will win in both.
I also don't really believe the fuel mileage is better for autos, AS LONG AS THE GEARING IS THE SAME, and it's an experienced driver (for both, but more important for the manual). There is a pretty significant loss still inside an automatic transmission - which one can see as heat that even requires cooling. That energy has to come from somewhere.

 

Good points. I was only referring to an improvement in published fuel economy figures. I'm sure if you were really trying to drive economically a manual would still have the edge.

 

The old C-6 tranny was good for eating up about 60 horsepower. I would think the newer trannies are better than that. (I hope)