2nd to 3rd upshift under low power
06-26-2017, 09:29 AM
#1
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2nd to 3rd upshift under low power
2006 F150 FX4 140K Cold air, Exhaust, leveled and on 35"
about 6 weeks now my truck under low power such as coming from a stop and starting to go slow around a turn and then once straight giving it gas the transmission should be in second but it has up-shifted early to 3 and then lugs until the rpms catch up and then accelerates correctly. However when accelerating normal or hard the truck goes through the gears just fine. No codes, transmission is full with clean fluid. Took it to my mechanic and found nothing to be wrong, does not feel that its the transmission itself. He did flash the learning computer and the truck did work perfect for 2 days then the problem came back. He suggested an after market tuner. Though i did not agree i got a bully dog gt and tried the different tunes and none made any deference. Kind of at a loss.
I have replaced the:
TCC solenoid
Dual Shift solenoid
Mass airflow sensor
transmission fluid change.
Bully Dog GT
Any suggestions?
about 6 weeks now my truck under low power such as coming from a stop and starting to go slow around a turn and then once straight giving it gas the transmission should be in second but it has up-shifted early to 3 and then lugs until the rpms catch up and then accelerates correctly. However when accelerating normal or hard the truck goes through the gears just fine. No codes, transmission is full with clean fluid. Took it to my mechanic and found nothing to be wrong, does not feel that its the transmission itself. He did flash the learning computer and the truck did work perfect for 2 days then the problem came back. He suggested an after market tuner. Though i did not agree i got a bully dog gt and tried the different tunes and none made any deference. Kind of at a loss.
I have replaced the:
TCC solenoid
Dual Shift solenoid
Mass airflow sensor
transmission fluid change.
Bully Dog GT
Any suggestions?
06-30-2017, 08:43 AM
#2
Junior Member
Thread Starter
Join Date: Oct 2012
Posts: 3
Likes: 0
Received 0 Likes
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2006 F150 FX4 140K Cold air, Exhaust, leveled and on 35"
about 6 weeks now my truck under low power such as coming from a stop and starting to go slow around a turn and then once straight giving it gas the transmission should be in second but it has up-shifted early to 3 and then lugs until the rpms catch up and then accelerates correctly. However when accelerating normal or hard the truck goes through the gears just fine. No codes, transmission is full with clean fluid. Took it to my mechanic and found nothing to be wrong, does not feel that its the transmission itself. He did flash the learning computer and the truck did work perfect for 2 days then the problem came back. He suggested an after market tuner. Though i did not agree i got a bully dog gt and tried the different tunes and none made any deference. Kind of at a loss.
I have replaced the:
TCC solenoid
Dual Shift solenoid
Mass airflow sensor
transmission fluid change.
Bully Dog GT
Any suggestions?
about 6 weeks now my truck under low power such as coming from a stop and starting to go slow around a turn and then once straight giving it gas the transmission should be in second but it has up-shifted early to 3 and then lugs until the rpms catch up and then accelerates correctly. However when accelerating normal or hard the truck goes through the gears just fine. No codes, transmission is full with clean fluid. Took it to my mechanic and found nothing to be wrong, does not feel that its the transmission itself. He did flash the learning computer and the truck did work perfect for 2 days then the problem came back. He suggested an after market tuner. Though i did not agree i got a bully dog gt and tried the different tunes and none made any deference. Kind of at a loss.
I have replaced the:
TCC solenoid
Dual Shift solenoid
Mass airflow sensor
transmission fluid change.
Bully Dog GT
Any suggestions?
Now it's starting to have a hard shifts from second to third while driving in traffic.
08-21-2017, 04:20 PM
#4
Junior Member
My truck has done this a couple times, although I've only had it for about 5 months. Since it only happened, literally, a couple times I wasn't too worried. But it does hard-shift from 1st to 2nd when driving in traffic. When it starts doing that, I just put it in Manual and leave it in 1st.
2012 F150 XLT, stock exhaust, stock suspension, stock intake. 5.0 V8
2012 F150 XLT, stock exhaust, stock suspension, stock intake. 5.0 V8
08-27-2017, 08:48 PM
#5
May be in the valvebody of the transmission. Get a schematic online of your model transmission valve body. Buy the SureCure kit and rebuild it. Also, while the valve body is off, you have access to the 1-2 and 2-3 accumulator pistons. These are known to wear out and are always replaced during a transmission rebuild. See video for more on that... https://m.youtube.com/watch?v=zStK_0CqHy8
Also, if the overdrive piston bore is worn out severely, this may cause a pressure failure that puts the truck into limping mode. Unfortunately, you cant just easily swap that w the improved piston from the SureCure kit (modified w o-ring to seal up the piston play). Theres a cutout in the transmission near the overdrive piston where you can use a tool (mechanics pick etc) to push the overdrive band over enough for the piston to catch the edge of it, but its tricky. Watch the video series I posted to damiliarize yourself w the overdrive band before attempting. Try that last. Chances are the problem is in the valve body or the accumulators. Heres the vid of a teardown on a 4r70w trans valvebody. Find out which one you have. https://m.youtube.com/watch?v=T8_wrj2xoKA
May be worth your while to grab one of those cheap, deep turkey pans from the Dollar Store, nice clean pan to drain the trans fluid into to reuse. Trans fluid is expensive and high in detergent which can ruin an older transmission. Get some cheesecloth and a 5 gal bucket and filter it out. Then put a new trans filter back in when done.
Also, if the overdrive piston bore is worn out severely, this may cause a pressure failure that puts the truck into limping mode. Unfortunately, you cant just easily swap that w the improved piston from the SureCure kit (modified w o-ring to seal up the piston play). Theres a cutout in the transmission near the overdrive piston where you can use a tool (mechanics pick etc) to push the overdrive band over enough for the piston to catch the edge of it, but its tricky. Watch the video series I posted to damiliarize yourself w the overdrive band before attempting. Try that last. Chances are the problem is in the valve body or the accumulators. Heres the vid of a teardown on a 4r70w trans valvebody. Find out which one you have. https://m.youtube.com/watch?v=T8_wrj2xoKA
May be worth your while to grab one of those cheap, deep turkey pans from the Dollar Store, nice clean pan to drain the trans fluid into to reuse. Trans fluid is expensive and high in detergent which can ruin an older transmission. Get some cheesecloth and a 5 gal bucket and filter it out. Then put a new trans filter back in when done.
Last edited by Spanky666; 08-27-2017 at 08:53 PM.