Since the day i bought my truck with 30,000 miles on it, i have notice that whenever i am cruising along doing any speed pretty much but lets say 60 down the road. I come to the top of the hill and let off the gas to coast to the bottom and then i step back on the gas to go up and then it downshifts. Everytime i take my foot off the gas and return it, it downshifts for a second then shifts back into overdrive. I can be doing 80 and it will still do it. Nobody has figured it out what is wrong. The PCM was reflashed even and it still does it. Anyone have a good idea?

 

Since you have no other information, I would replace the TPS and make sure the voltage readng is within spec.
You may have an open or dead spot in it's travel.
The transmission shifting versus load and rpm is highly dependent on the TPS signal as well as some other sensors.
Have you looked for any fault codes set?
Reflashing the PCM can't over come a faulty operation out side the PCM.
Good luck and let us know if you are lucky enough to get the problem.

 

Is it just the torque converter unlocking?

(pssst: manuals dont have that problem )

Really, is it really a downshift like locking out overdrive, or pulling the shifter to 2, or just a TC unlock/relock?

Adrianspeeder

 

If I interpet the post correctly, he is saying the trans shifts everytime the throttle is varried over a small normal range.
Yes the trans will shift if the PCM decided there is not enough power to move the truck at the requested throttle position.
Normally you should be able to change throttle level over a reasonable range without downshift.
This range varies with rpm and power the engine makes.
Downshift at less than 2500 rpm can be often if acceleration is called for but at 2000 rpm and 70 mph on a reasonable flat road should not cause downshifing.
Admittidly there is little throttle response but a gradual increase in throttle will raise speed without down shift.
I have no shifting problems with my truck, so far.
One thing I notice is the other Ford SUVs like the Explorer cruise more effortless than an F150. Less weight and a different transmission and PCM programming.

 

Hi.

I had the same issue. It was the TC lockup schedule.

I mentioned it to TP when he was constructing my custom tunes for my SCT 9100.

The behaviour is gone after applying the tuning. If I uninstall the tuning ( return to stock) the issue resurfaces, so I'm confident the problem has been properly addressed.

The TC lockup schedules for each shift point are parameters that can readily be modified via custom tuning. They can also be further 'tweaked' ( to the point where I can recreate the symtoms ;-)) ), via ExtremeTune by the end-user, given your desire to do so, and the possession of your tune files in *.XTR format.

Bear in mind that Bluegrass has made valid points - the above assumes all your other engine controls/sensors are operating correctly; otherwise tuning ( or factory reflashing) is not going to fix a thing.

Cheers

 

Ya it will even do it when im out of overdrive. I might check with my mechanic and see what he thinks about replacing the tps if that is the most possible thing that is wrong. I guess i have gotten along with it for so long i dont notice it as much. To me it is still alot of shifting on a tranny and i want to minimize that as much as i can. Whats it take to replace the tps? if that is the problem.

 

I agree with MGDfan you are feeling the torque converter in stock trim when you let up on the accelerator while coasting the converter unlocks when you go to acclerate tge rpm's go up for a second or two and then will pull back down feels like a shift when the converter lock up clutc reapplys. This is normal in stock trim and can be quite anoying, the up side with a good custo tune this and a lot of other transmission related shift problems can be fixed. Mike Troyer addressed all these problems in my custom tune, now it shifts and locks up the way I like it, and I might add that a proper tune will drop trans temp by 30+ degrees, with a lot less trans wear.

 

NORMAL.

 

Canoe, if your happy with your trans running that way, good for you, but not me.
Mine does not do any of that unless I cammand it to down shift with more throttle than the engine has power to accelerate with.
.................................................. .........................................
It is ammazing how much difference there is in PCM programming, and tolerences in the transmission operation.
Sometimes they are to far oppisite each other and cause these effects.
The dealers are often not interested enough to solve the problems and will tell people anything, then the owner becomes at the mercy of the dealer, because he has no knowledge of the possible causes and fixes.
A for instance to ponder:
For a couple years, the larger trucks that are used with crane assemblies need to raise the idle to operate the boom and other features.
The factory canceled the program line that does this function and had to reflash the customer trucks PCM as well as reflash the the assembly line PCMs to bring back the feature.
Go figure. A bunch of monkeys could do as well.
We tend to think, in this day and age, that most everything in perfected.
It is pretty good, but it's the decision making by people that have not the knowledge of the bigger picture, that is the MOST defective of all.

 

TC lockup issue

 

It's the tc not staying locked. My 01 does it too and it is really annoying.

 

Call Mike Troyer, He can tune that out of you're truck and make the trans. run 30 degree cooler. My fluid looks like the day I put it in, it used to get strong smelling and dark within no time. His tunes make the differance.

 

 

Canoe, let me tell you more about this.
All the way back to at leat 86 in the little A4LD Rangers and Bronco II , and all the E shifting transmissions, they all drop the lockup momentary with "throttle lift or brake application".
Did you know that?
The only way you can see it is by watching the tach and playing games with the throttle and brake unless it is so bad you feel an objectional result.

My 02 4r70w will do all that, they all will do it, it's in the program and there is a reason for it to be that way..
Doing it to an excessive level resulting in hunting , banging, is not normal.
I have an 86 Ranger 4x4 with the A4LD. It went into hunting in 2nd,3rd and OD. It was a bad computer.

 

I started working at a Ford dealer in 84. In 85 I started bulding transmissions there untill becoming Shop Forman in 94. I still build a few when we get behind. Have done 3 torqueshifts in the past month due to the high volume recall on them. Somewhere in the mid 90's, Ford quit unlocking converters below a certin speed, unless you went to heavy throttal. Dont remember the vss or tp %, or the year they started that, seems like 97 ?, that it unlocks at.
Just from what I read, without being able to test drive, it sounded normal.Back to what I said about the Superduty unlock complaint, I was told by the Ford Tech Hotline, that sensative people were complaining about the bump( in the driveline) when the converter releesed, is the reason the programmimg was changed.

Now since I dont know much about Ford Transmissions, could you please tell me which way the sun gear turns, in 2nd gear of a simpson geartrain?