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Poor trans shifting theory investigation

Poor Trans shifting theory  

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2 hours ago, Fingernip said:

I think the 8F35 comes from the GM 9 speed design which doesn't share ratios with any of the existing transmissions. The 8F57 is a 6F55 but modified with 2 more gears it retains all the same ratios as the GM 6T70.

 

Oops yes I thought we were talking about the 8F35.

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2 hours ago, Fingernip said:

I think the 8F35 comes from the GM 9 speed design which doesn't share ratios with any of the existing transmissions. The 8F57 is a 6F55 but modified with 2 more gears it retains all the same ratios as the GM 6T70.

 

You are correct.

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My vehicle is still at the dealer (tomorrow will be a week now again). Has anyone been able to confirm that their transmission behaves different than mine does? If the gear ratios posted are accurate, and the calculator I found too, then we should all be seeing the same behavior with 2nd and 3rd gear.

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19 minutes ago, boosted_st said:

My vehicle is still at the dealer (tomorrow will be a week now again). Has anyone been able to confirm that their transmission behaves different than mine does? If the gear ratios posted are accurate, and the calculator I found too, then we should all be seeing the same behavior with 2nd and 3rd gear.

I have not been able to get the time or a safe place to carefully monitor what happens in D mode with 2,3 & 4 shifts.  But I've had the TSB applied and I know there is still some strange stuff going on.  In paddle-shift/D mode, it almost seems like the display shows 3, then I hear no change, but then it shows 4.  In S mode, because it doesn't auto-upshift, it will go into each gear but it really flares when going from 3 to 4.  There is definitely some global problem with 3 & 4, perhaps they're just too close and maybe the ECU will only use them both properly when under heavy tow-load or something, otherwise it seems to want to skip but doesn't do it elegantly.   I'll see if I can get a chance to really dig into this--I need to be in a safe place because I can only use my ears to tell the gear it's actually in when in D mode.    The main TSB issue I had aside from the 3 & 4 was the clunk when going into reverse from park, and that has not happened at all since the fix.

 

The TSB though specifically calls out a flare on the 4-5 shift, and I never had any issue with the 4-5 shift--it was always the skipping of the 3 or 4 (I never could really tell which) that I had issue with.

 

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I didn't try it accelerating hard but just playing with the paddle shifters in drive I get no harsh shift or anything, rpms drop roughly 400 rpms, which looks to be expected going by the gear ratios. It stays in 3rd with no issues. Streets are full of ice and snow so I can't copy exactly what you do. Not sure what to tell you other than are you sure your dealer dowloaded the latest tsb flash and isn't using just the last one he downloaded? As the one I had applied from the latest tsb was a huge improvement and even paddle shifts in drive seem quite quick and

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On 1/9/2020 at 5:14 PM, Perblue said:

I didn't try it accelerating hard but just playing with the paddle shifters in drive I get no harsh shift or anything, rpms drop roughly 400 rpms, which looks to be expected going by the gear ratios. It stays in 3rd with no issues. Streets are full of ice and snow so I can't copy exactly what you do. Not sure what to tell you other than are you sure your dealer dowloaded the latest tsb flash and isn't using just the last one he downloaded? As the one I had applied from the latest tsb was a huge improvement and even paddle shifts in drive seem quite quick and

 

Thanks for the info... if someone could make a video it might give me more ammunition. I got the vehicle back today and just as I expected, NO fix for the transmission and they claim it's working right because the computer says so. 😣

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On 1/10/2020 at 7:29 PM, boosted_st said:

 

Thanks for the info... if someone could make a video it might give me more ammunition. I got the vehicle back today and just as I expected, NO fix for the transmission and they claim it's working right because the computer says so. 😣

 

Go tell them that 'THE COMPUTER' is only as smart as the ASS that programmed it, and they are JUST AS BIG AN ASS for believing THE COMPUTER...

There are plenty of things that can go wrong that are NOT tied to a sensor that alarms the computer.

 

How did they diagnose problems PRIOR to computers ?

Did they forget how to properly diagnose a transmission problem ?

I bet if you were to take it to a transmission shop, you would get back a report of all the problems it has.

 

Pete...

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On 1/9/2020 at 4:58 PM, Jombi said:

The TSB though specifically calls out a flare on the 4-5 shift, and I never had any issue with the 4-5 shift--it was always the skipping of the 3 or 4 (I never could really tell which) that I had issue with.

 

 

Yep, I had the same issue. Third would disengage and fourth took forever to engage. In between the engine would flare because there was nothing engaged.

TSB fixed that problem.

 

Pete...

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11 hours ago, MENINBLK said:

 

Go tell them that 'THE COMPUTER' is only as smart as the ASS that programmed it, and they are JUST AS BIG AN ASS for believing THE COMPUTER...

There are plenty of things that can go wrong that are NOT tied to a sensor that alarms the computer.

 

How did they diagnose problems PRIOR to computers ?

Did they forget how to properly diagnose a transmission problem ?

I bet if you were to take it to a transmission shop, you would get back a report of all the problems it has.

 

Pete...

 

I did, I all but said their techs are idiots and monkeys if all they can do is fix something if the computer says there is an issue. Dealer techs seem like level 1 support people now, if there isn't a defined process to fix a well known problem they are useless.

 

I have thought about going to a transmission shop, but I really don't want to spend money diagnosing a car I just paid over 50K for either. Ford needs to get their 5h1t together!

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There is ONE THING you can say to the dealership.

 

All these transmission problems that we are having that are FIXED by the TSB are problems that the Computer (PCM) never flagged.

Brand NEW Edge ST/Titanium/and others owners are having transmissions rebuilt and replaced with problems that are not detected by the computer (PCM).

 

This conversation is at an Engineering level that is way above the pay grade of a dealership and it requires a Field Representative to talk to.

 

Pete...

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On 1/6/2020 at 5:39 PM, boosted_st said:

I requested an update from the dealership and as I thought... it's BS and they aren't going to fix anything... I'm so over this crap and 100% regret buying this dang vehicle.

 

"The tech got back with me and Charlie, he stated he is able to monitor 3rd gear is engaging, the reason it's in such high RPM compared to 4th, is 4th is considered an overdrive gear. At this point, there is no problem."

 

My Response:

 

"If other owners don't see the same behavior that can't be correct, especially when 3rd is never actually used. And 2nd and 3rd having identical rpms doesn't make sense either. No difference between 2nd and 3rd IS an issue."

 

This will be the last Ford I ever own and will tell anyone and everyone to steer clear of Ford as well. This is beyond ridiculous now.

 

Did they mention anything at all about the bucking? It should never buck when changing gears and there is no excuse for it. Did you get a service report with detailed description of the trouble shooting methods? It would also have the customer complaint spelled out.. if it is not exactly what you told them you need to complain to Ford. Definetly try another dealership though... they are talking completely out of their butts... "4th gear is an overdrive gear....." 5th is 1:1. By no definition is 4th an overdrive gear in the 8F57.

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" 4th is considered an overdrive gear"

Yes this is a bizarre statement coming from a dealer who should know.  It may be an "extra" gear (compared to the previous 6-speed) but overdrive is only 7 & 8 in the 8F57; OD is by definition a ratio of less than 1.0: 1.   

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3 hours ago, Fingernip said:

Did they mention anything at all about the bucking? It should never buck when changing gears and there is no excuse for it. Did you get a service report with detailed description of the trouble shooting methods? It would also have the customer complaint spelled out.. if it is not exactly what you told them you need to complain to Ford. Definetly try another dealership though... they are talking completely out of their butts... "4th gear is an overdrive gear....." 5th is 1:1. By no definition is 4th an overdrive gear in the 8F57.

 

Nope, the reports have never been detailed with what they actually did which really makes me wonder what was done to test anything. I have a case open with Ford Customer Care (Is there a better one?). Even though I have heard bad things about other dealers, I'll give that a shot and see how it goes. I just really don't want to waste more of my time dealing with this. Pretty sure the vehicle has been at the dealer 5+ weeks since I bought it at the end of August 2019.

 

3 hours ago, Jombi said:

" 4th is considered an overdrive gear"

Yes this is a bizarre statement coming from a dealer who should know.  It may be an "extra" gear (compared to the previous 6-speed) but overdrive is only 7 & 8 in the 8F57; OD is by definition a ratio of less than 1.0: 1.   

 

You both make really good points about what overdrive really is and that makes sense. I've never looked into that but this "OD is by definition a ratio of less than 1.0: 1." totally makes sense to me and means their transmission specialist is talking out of his ass.

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There are only TWO overdrive gears, 7th and 8th.

6th gear is 1:1.

If 4th gear is an overdrive gear, then so is REVERSE !!!

 

Transmission specs are here on page 2.

ST 8 speed transmission has a different gear set.

https://media.ford.com/content/dam/fordmedia/North America/US/product/2019/edge/2019-edge.pdf

 

 

They don't even know the definition of an overdrive gear.

 

Pete...

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47 minutes ago, MENINBLK said:

There are only TWO overdrive gears, 7th and 8th.

6th gear is 1:1.

If 4th gear is an overdrive gear, then so is REVERSE !!!

 

Transmission specs are here on page 2.

ST 8 speed transmission has a different gear set.

https://media.ford.com/content/dam/fordmedia/North America/US/product/2019/edge/2019-edge.pdf

 

 

They don't even know the definition of an overdrive gear.

 

Pete...

 

I'm with ya, I have another appointment with a different dealership tomorrow morning now. Thank you for posting the tech spec sheet! I've been trying to locate that without success.

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I found another calculator online Engine RPM Calc and with a tire diameter of 29.3" (265/40 R21)

 

RPM     Gear     MPH     Ratio

4898     2nd       40         3.15
4462     3rd        40         2.87

2861     4th        40         1.84

2192     5th        40         1.41

1555     6th        40         1.00

 

This to me would make more sense and would fall in line with what everyone else is seeing as "normal", even the 3 - 4 difference seems about right from what I have seen (my opinion is they could have done this better). 6th seems about right too, lots of surface streets here are 40 mph so I'm doing the speed all the time. Feel free to correct me if I'm wrong.

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One thing you need to remember is that on the ST, the 380 Ft Lb of Torque maxes out at 3000 rpm.

To keep the transmission in the "Sweet spot", it needs to shift at about 3000 rpm.

After the 3000 rpm, the torque doesn't get any higher.

 

Pete...

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35 minutes ago, MENINBLK said:

One thing you need to remember is that on the ST, the 380 Ft Lb of Torque maxes out at 3000 rpm.

To keep the transmission in the "Sweet spot", it needs to shift at about 3000 rpm.

After the 3000 rpm, the torque doesn't get any higher.

 

Pete...

Yes but generally the actual horsepower (actual work done) is what you want, so I think ideally you’d shift out of the gear at highest Hp rpm, near redline, and the ideal gear ratio of the next gear would have you start at or near that max torque rpm so there’s no bogging, and ride that Hp train back to redline again.  
 

If the ratio of the next gear is too close, the overhead of the shift itself negates the gain because you’re only riding half of the horsepower sweet spot, lasting too short a time to make the shift worth it.    So I think some of those ratios were chosen for slower speed, heavy load towing, and should be skipped when racing.

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Transmissions are rated on Torque, not Horsepower.

 

Pete...

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36 minutes ago, MENINBLK said:

Transmissions are rated on Torque, not Horsepower.

 

Pete...

Yes they are rated for what they can withstand on torque from a design perspective. But I’m referring to the strategy of when to upshift and where the ratios should be.  You don’t want to upshift this ST at 3000 rpm, your gonna want to upshift at the engine’s Hp peak near redline and begin the next gear where the torque is, at 3000. 

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335 HP comes in at 5500 rpm.

My Edge doesn't wait for 5500 rpm to shift.

Not even getting on the highway.

 

Pete...

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24 minutes ago, MENINBLK said:

335 HP comes in at 5500 rpm.

My Edge doesn't wait for 5500 rpm to shift.

Not even getting on the highway.

 

Pete...

Mine doesn’t either with the stock tune, but with the Livernois tune it goes just past 5500 Before shifting and the next gear has no bogging, it’s giddy-up and go immediately and the shift itself is so fast it feels like a double-clutch trans. That shift is what catapults me ahead of non-turbo, larger engine cars because I’m in the boost already and I pull away easily.  
 

Of course that tune is probably adding nearly 30 hp at the crankshaft, so I’m probably at ~365 Hp.  Mine, with that tune will take care of the Lexus RS Fsport, and just barely eek out against a BMW X5 Xdrive.  Another member hear had troubles with a Honda Passport while his Edge was in stock tune, I was surprised to learn the Passport is rated at 5.8 0-60.  
 

I really wish we didn’t have to put aftermarket tune on these to get what I would consider “true” ST performance to outdo some of these other SUVs, but it’s where we’re at unfortunately, and for me the ~$600 was worth it.  And I’m only on the 91 tune, I had the 93 tune for a week or so and it was absolutely vicious, but I didn’t have my dragy then so I don’t have any real numbers.  I’m guessing 0-60 in the high 4s but due to turbo lag it’s hard to realize much more gains in a roughly 350 foot run to 60 mph, but dragy or not I felt invincible on the highway with that 93 tune, totally effortless 80 to 120 mph—almost scary.

 

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My next investment...  :)

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8 hours ago, MENINBLK said:

335 HP comes in at 5500 rpm.

My Edge doesn't wait for 5500 rpm to shift.

Not even getting on the highway.

 

Pete...

The Edge ST shows on dyno tests that peak torque is just over 3000rpm and peak HP is just under 4000 rpm. After 4k rpm the power output trails off and it falls on its face well before redline. 

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2 hours ago, Fingernip said:

The Edge ST shows on dyno tests that peak torque is just over 3000rpm and peak HP is just under 4000 rpm. After 4k rpm the power output trails off and it falls on its face well before redline. 

Yes but you still want to stay in gear and get that last 1500 rpm from 4000 to 5500.  Just because the HP isn't at peak after 4000 doesn't mean it's time to shift--you're still accelerating greatly between 4000 & redline so given the overhead of the shift you want to use that all up.  I'd rather spend that last half second or whatever it takes to get from 4000 to 5500 and make the most of what the transmission spent on shifting time--and then do the upshift.   If every shift was only using the rpm range from 3000 (or a little above) to 4000, you'd need a lot more gears and the overhead of shift time would kill the 1/4 mile time.   

 

I just came home from an appointment and just trying to watch the tach, I see that the sweet spot (and this is with Livernois so it will differ from stock) is around 3500--that's when I feel the Gs come on string and that is the point where I want the upshift to begin.  Then I'll take that shift and ride it all the way to just before redline--and ideally for acceleration runs each shift should be set to so the next gear starts in the 3000/3500 range--whatever that sweet spot is.  But being a multi-use vehicle, it has those extra gears for towing, etc., so it's not perfect.  I'm going to find some time and try some runs using the manual paddle and see if double-tapping the upshift will go to the one I want without delay.  I really wish the normal D or S modes would clearly display the actual gear we're in so I'd have a better idea of what's going on in non-paddle mode, because I'm still not sure which gear it's skipping but given the ratios shown--I'm OK with it skipping the 3 or 4 gear because they're so close and I think it needs to skip one of those.

--Jim

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