10R80 Owners - ULTIMATE M6G 10R80 Facts + Resolutions to harsh or no shift conditions

[Rickloreto]

Gotcha, thank you.
Sounds like I should invest in a Forscan tool.
I don't have a Windows computer, just Mac OS. Are these same parameters adjustable in the Lite versions on iOS/Android?

I’m really not sure on that one, i’ve only used their EX cable with my laptop (windows) but I think I saw during my research there are some things you cannot do with the lite version.

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[Zathras]

I understand why the BCM might need to be updated for a tire size change so that the speedo reads correctly, but I'm still confused why this affects the transmission shift quality. In most cars, the auto shift points would be defined by some combination of throttle position, vehicle speed, and maybe engine RPM (plus maybe some adjustments for things like trans fluid temp). So for example, let's say you made the tire size smaller so the wheels are rotating faster and the speedo is now reading "high" compared to the true vehicle speed. If the car was originally programmed (at some constant throttle position) to upshift 2-3 at 50 MPH, (just as an example) let's say the car (via wheel speed sensors or speedo, however it's measured) reaches that indicated "50 MPH" shift speed at an actual speed of 45 MPH. So it now makes the commanded gear shift 5 mph earlier, compared to the true vehicle speed. But the vehicle doesn't know or care that it is shifting "early," it's just processing the data until it reaches a condition that triggers a shift based on the programmed shift logic, and operating the shift solenoids like it always did.

I guess if there was a lot of slip in the torque converter, there could be some kind of "speed vs expected engine rpm" mismatch, but it seems like a 3% change in tire circumference would be too small to matter.

 

[Rickloreto]

I understand why the BCM might need to be updated for a tire size change so that the speedo reads correctly, but I'm still confused why this affects the transmission shift quality. In most cars, the auto shift points would be defined by some combination of throttle position, vehicle speed, and maybe engine RPM (plus maybe some adjustments for things like trans fluid temp). So for example, let's say you made the tire size smaller so the wheels are rotating faster and the speedo is now reading "high" compared to the true vehicle speed. If the car was originally programmed (at some constant throttle position) to upshift 2-3 at 50 MPH, (just as an example) let's say the car (via wheel speed sensors or speedo, however it's measured) reaches that indicated "50 MPH" shift speed at an actual speed of 45 MPH. So it now makes the commanded gear shift 5 mph earlier, compared to the true vehicle speed. But the vehicle doesn't know or care that it is shifting "early," it's just processing the data until it reaches a condition that triggers a shift based on the programmed shift logic, and operating the shift solenoids like it always did.

I guess if there was a lot of slip in the torque converter, there could be some kind of "speed vs expected engine rpm" mismatch, but it seems like a 3% change in tire circumference would be too small to matter.

Yeah its silly but its kind of silly how the sensors make the cars/trucks behave when going out of that 3% the module accounts for up/down from the oem tire size and that = clunky feeling with weird shifting stuff since I believe it reads off abs/outputshaft speed sensors mainly in mustangs having the infamous drag pack when going 305/45r17’s its like a 5% size difference. And of course the adaptive learning learns all the miss matches and behaves weird. Thankfully forscan helps a lot.

 

[saiyangt]

Yeah its silly but its kind of silly how the sensors make the cars/trucks behave when going out of that 3% the module accounts for up/down from the oem tire size and that = clunky feeling with weird shifting stuff since I believe it reads off abs/outputshaft speed sensors mainly in mustangs having the infamous drag pack when going 305/45r17’s its like a 5% size difference. And of course the adaptive learning learns all the miss matches and behaves weird. Thankfully forscan helps a lot.

So Ford took a look through Oasis, found no codes but did acknowledge that the larger wheels could mess with the shift points. They weren't able to amend the size in the BCM and suggested that my only option is to change it myself via FORESCan.

Looks like I'll need to buy a compatible OBD reader!

While I was waiting for the tech to finish I took another 10-speed for a test drive.
To my surprise, the shifts were even worse! Starting to wonder if this is just a messy feeling transmission... Apparently it holds up great to big power, but driveability might not be great.

 

[Rickloreto]

So Ford took a look through Oasis, found no codes but did acknowledge that the larger wheels could mess with the shift points. They weren't able to amend the size in the BCM and suggested that my only option is to change it myself via FORESCan.

Looks like I'll need to buy a compatible OBD reader!

While I was waiting for the tech to finish I took another 10-speed for a test drive.
To my surprise, the shifts were even worse! Starting to wonder if this is just a messy feeling transmission... Apparently it holds up great to big power, but driveability might not be great.

Once the tire size is corrected and pcm relearn applied you do have to reset the adaptive tables but sometimes depending on how bad it is it might take anywhere from 60-150 miles of mixed driving up to start/stop city and hwy driving to feel 100% like it should. But driveability will be better once all this is done. If its a brand new car it also could take a few miles to adapt if that makes sense. I guess not every car/truck is smooth but of course feeling yours vs a new one will be very different as well. But i’ve heard from others and myself of Ford being unable to do it properly like we do with forscan.

 

[ChuckBilodeau]

Ok, I have yet to read this entire post, but here is my short story..

I built a 2020 Mustang ecoboost auto for road racing. I chose the auto; I was looking for a transmission that would allow me to stay in boost all the time vs shifting a manual tranny and falling out of boost all the time. I knew it could have heat issues, but I figured with only 350hp ecoboost, it would be fine.

Got on track last year, everything was fine at first but then it started overheating and acting super weird, slipping, missing gears, etc. We also had some fluid coming out of what we think is the vent hole. The problem started happening at lower and lower temps.

We opened the transmission over the winter and everything looked fine (not sure the tech was qualified to REALLY inspect everything), and we changed the clutches to the Raybestos HD ones just in case they were the problem, but how could they be with my lever of power?!

At the same time, I upgraded the cooling (heat exchanger, large PPE oil pan, radiator ducting, etc). Went back on track and the heat thing seems to be under control, never got above 103c. But now it does the same thing at even lower temps, under 100c (212f).


I am suspecting the TC is now the problem. Is it possible it overheated and now acts up at even lower temps? Could an upgraded TC help me? Like Circle D or Suncoast... I want to be able to run 1hr races with no problem.

Should I just give up and go manual?! That would be sad...

 

[Alan2955]

So Ford took a look through Oasis, found no codes but did acknowledge that the larger wheels could mess with the shift points. They weren't able to amend the size in the BCM and suggested that my only option is to change it myself via FORESCan.

Looks like I'll need to buy a compatible OBD reader!

While I was waiting for the tech to finish I took another 10-speed for a test drive.
To my surprise, the shifts were even worse! Starting to wonder if this is just a messy feeling transmission... Apparently it holds up great to big power, but driveability might not be great.

 

[Alan2955]

Sorry to hear you’re having all these problems. I went through the same thing last summer and kind of gave up on it and traded it off. Beautiful car but the transmission irritated the heck out of me. I also drove about five other ones which were either a tad better or a lot worse but all were subpar vs. other automatics I’ve ever driven. I’m hoping maybe someday Ford straightens these things out and I could try another Mustang again. For what it’s worth I had a 2014 with a six speed automatic and it shifted very nicely.

 

[Rickloreto]

So i’ve come to find out a few more things. I did a PCM reset all adaptations, enabled performance shifting, recalibrated the ABS longitudinal speed sensor and reloaded the tune and it now feels like it did when I bought the car lol only thing with resetting all adaptations it might have slight driveability issues for a few 30 or so miles but damn its so smooth other than having a built suspension and noisier 3.73 torsen dif but this literally fixed every single issue I was even thinking on doing a fluid/filter transmission service at ford but this corrected everything. The only thing forscan cannot do is a miss fire neutral profile correction which is to be done any time you replace either sensor or part in the powertrain just so it relearns the new position of anything that was moved/replaced even spark plugs so i’m doing that soon with a friend that has a diagnostic tool for that and even an electrical steering relearn just because its there. Fyi if replacing battery or even disconnecting it it needs a BMS reset which can be done by ignition on-pull the high beams 5 times and then 3 times step on brake pedal and battery light should blink a few times and you are good, also can use the forscan service option for it. I’ve seen in the forums not many dealerships do the bms reset like if they just want peoples money since that is needed to prolong battery life and I did notice the voltage stays higher in the 14.1-14.2v range and before doing the reset it fluctuated like 12-14v consistently. Even high speed vibration is gone over 75mph god it feels nice and falling in love with it again!

 

[ChuckBilodeau]

Sorry to hear you’re having all these problems. I went through the same thing last summer and kind of gave up on it and traded it off. Beautiful car but the transmission irritated the heck out of me. I also drove about five other ones which were either a tad better or a lot worse but all were subpar vs. other automatics I’ve ever driven. I’m hoping maybe someday Ford straightens these things out and I could try another Mustang again. For what it’s worth I had a 2014 with a six speed automatic and it shifted very nicely.

I hear you! But I'm pretty sure its more than just the transmission not being up to par, something is definitely broken...

 

[fatbillybob]

Ok, I have yet to read this entire post, but here is my short story..

I built a 2020 Mustang ecoboost auto for road racing. I chose the auto; I was looking for a transmission that would allow me to stay in boost all the time vs shifting a manual tranny and falling out of boost all the time. I knew it could have heat issues, but I figured with only 350hp ecoboost, it would be fine.

Got on track last year, everything was fine at first but then it started overheating and acting super weird, slipping, missing gears, etc. We also had some fluid coming out of what we think is the vent hole. The problem started happening at lower and lower temps.

We opened the transmission over the winter and everything looked fine (not sure the tech was qualified to REALLY inspect everything), and we changed the clutches to the Raybestos HD ones just in case they were the problem, but how could they be with my lever of power?!

At the same time, I upgraded the cooling (heat exchanger, large PPE oil pan, radiator ducting, etc). Went back on track and the heat thing seems to be under control, never got above 103c. But now it does the same thing at even lower temps, under 100c (212f).


I am suspecting the TC is now the problem. Is it possible it overheated and now acts up at even lower temps? Could an upgraded TC help me? Like Circle D or Suncoast... I want to be able to run 1hr races with no problem.

Should I just give up and go manual?! That would be sad...

Chuck overheat just once can be fatal on A10. Burp out vent happens when too hot. Make sure fluid level is right. Tc is known victim. Don't let A10 get hot!!!

 

[ChuckBilodeau]

Chuck overheat just once can be fatal on A10. Burp out vent happens when too hot. Make sure fluid level is right. Tc is known victim. Don't let A10 get hot!!!

Ok, so you think the TC could be the cause? The mechanic did not see anything unusual, but like I said, I'm not sure he knew where to look. Would it be super obvious that the TC failed when you open the trans?

That would be great news considering... Do you know how the TC fails at high temps? Anyway, I ordered a new TC, of course like everything right now, it's BO. But it would mean that the 2 main possible causes, (clutches and TC) would have been changed in this transmission. Trying everything here not to have to change the entire assembly. Racecar=no warranty.

I spoke to the guys at circle D, they said that for road racing, the OEM TC was my best option, their TC would not help me in any way.

 

[ChuckBilodeau]

has anyone tried this? Does it fit 2018+ 10r80 mustang?

C&R Auto Trans Cooler Mustang GT 2015-2016

 

[shawn.m]

Had no shift when cold Park to Drive OR reverse to Drive. Fine rest of day but had to warm up car for 5 minutes. Turned into a complete transmission rebuild at Ford dealer under warranty. 47.5k miles. Bad TQ, pump and input shaft - I asked them to also replace any bad friction plates at same time.

Was within the 60k and within 90 days of purchase so CarMax says no deductible and here is free rental car until it comes back.

 

[18Crimson]

Have had the same reported harsh downshift from 6-1. Lag / harsh up shift 3-5. And the harsh drive/reverse. I've taken it in 5 times now. Have had the valve body replaced twice. And had the trans reset or whatever 3 separate times. Anyone have any ideas? Getting it looked at once again next week. Just tired of not being able to enjoy my car.

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