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Discussion Starter #1
From a dead stop with foot on brake, switch from D to R. The transmission seems to do something, engine pitch changes. Is this just a change to the transmission (changing the lockup?) or does the transmission kick down to 1 (implying that from a dead stop all modes but R start out at 2)?

Or is it something else altogether?
 

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From a dead stop with foot on brake, switch from D to R. The transmission seems to do something, engine pitch changes. Is this just a change to the transmission (changing the lockup?) or does the transmission kick down to 1 (implying that from a dead stop all modes but R start out at 2)?

Or is it something else altogether?
The trans is in N in all modes but race and manual when the vehicle is stopped .
 

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The trans is in N in all modes but race and manual when the vehicle is stopped .
When stopped at lights in DNA modes with the foot on the brake, I can feel the car trying to push forward. Isn't that the gearbox trying to drive via the torque converter? If so how could it be in Neutral?
 

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All new ZF transmissions, and likely others, since the mid 2000s go into a sort of neutral at a stop to save gas. If you open the exhaust while stopped in gear and holding the brake down, then lift off the brake slightly while staying stopped you can hear the RPM drop and then eventually rise again as the trans goes in and out of drive. I dont think its technically in neutral at a stop, I believe its some sort of hydraulic relief that reduces torque transferred into the trans (perhaps pressure lowered into the torque converter? No idea) and then when the computer sees a slight change in brake pedal position it reengages drive. In race mode, this "neutral" mode does not happen so its like a traditional old auto.

There also seems to be a minimum brake position to engage this, so perhaps if you are barely depressing the brake enough to stay stopped it doesnt engage. Ive definitely noticed it seems like there are times it doesnt happen, but with the exhaust open you can really clearly hear when its going in and out.
 

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When stopped at lights in DNA modes with the foot on the brake, I can feel the car trying to push forward. Isn't that the gearbox trying to drive via the torque converter? If so how could it be in Neutral?
Mine seems to move forward about 2/3 of the time. About 1/3 of the time, it feels like I have a hill assist feature where the car is stopped and I have to actually press the gas (once the light turns green) to move forward.

Maybe if you're stopped at a light long enough with your foot on the brake, it engages neutral?
 

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Discussion Starter #6
Mine seems to move forward about 2/3 of the time. About 1/3 of the time, it feels like I have a hill assist feature where the car is stopped and I have to actually press the gas (once the light turns green) to move forward.

Maybe if you're stopped at a light long enough with your foot on the brake, it engages neutral?
This Neutral shifting thing makes sense.

Try this experiment:
1. from a dead stop in D or N or A, with radio off, foot firmly on brake
2. slowly let your foot the brake, at some point in time, you'll hear the engine change pitch and the car will lurch a little bit.
3. repeat in R mode, this doesn't happen.

It's probably partially why people say it's easier to come to a smooth stop and make a smooth start in R mode.
 

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It's probably partially why people say it's easier to come to a smooth stop and make a smooth start in R mode.
It doesnt happen until youre stopped for a few seconds so I doubt thats related. I think that is because all these new transmissions with a pile of gears have pretty short 1st and 2nd gears so the trans wants to not downshift to 1st until youre at like 1-2 mph. So the downshift happens when youre basically hitting that complete stop which most people dont really do, so the transmission is downshifting into 1st when you are either finishing your stop or releasing the brake and going to gas and it results in kind of a strange jerky stop/go situation. In race it downshifts to 1st at a higher speed so you are in 1st well before the stop and dont get that poorly timed downshift. In my other ZF 8HP70 equipped vehicle this is actually a bunch worse and it either ends up leaving in 2nd if you are lucky, or placing a very leisurely 2-1 shift while trying to leave the stop sign.
 

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When stopped at lights in DNA modes with the foot on the brake, I can feel the car trying to push forward. Isn't that the gearbox trying to drive via the torque converter? If so how could it be in Neutral?
it should be in N most of the time....you can feel it if you cycle between auto and manual mode by moving the shifter left and right..you should hear a slight change in sound .. @Hoooper is correct that its not really in N but in an unlocked state.... I forget exactly how its done but I think they release the D clutch to decouple the rear gear set.....but again, its been a long time since I took an 8HP class....
 

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Discussion Starter #9 (Edited)
It doesnt happen until youre stopped for a few seconds so I doubt thats related. I think that is because all these new transmissions with a pile of gears have pretty short 1st and 2nd gears so the trans wants to not downshift to 1st until youre at like 1-2 mph. So the downshift happens when youre basically hitting that complete stop which most people dont really do, so the transmission is downshifting into 1st when you are either finishing your stop or releasing the brake and going to gas and it results in kind of a strange jerky stop/go situation. In race it downshifts to 1st at a higher speed so you are in 1st well before the stop and dont get that poorly timed downshift. In my other ZF 8HP70 equipped vehicle this is actually a bunch worse and it either ends up leaving in 2nd if you are lucky, or placing a very leisurely 2-1 shift while trying to leave the stop sign.
When I come to a stop in D/N/A it's not very smooth, no matter how hard I try (this is a common complaint about the QV obviously) and a lot of people attribute it to the brake by wire, but I think the transmission plays a part it in. If I come to a really slow stop (as in creep-level slow, as slow as you can possibly go, such as when you're in stop and go traffic), I always felt something change a bit, almost like I was being tapped on the bumper... I think this shifting explains that. In Race mode, I don't feel the same thing (although obviously it's not common for people to use Race mode in stop and go traffic, but it proves the point).
 

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Stops in d/n/a are smoother in manual vs auto in my experience
 

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Here is another question about power train changes in DNA: is 505 hp in Quads only achieved in Race mode? If not, is it also achieved in Dynamic mode? It clearly isn’t in N or A mode
 

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I just tried it and there is a definite change in Race like the gear is engaging in Race as OP described
 

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Here is another question about power train changes in DNA: is 505 hp in Quads only achieved in Race mode? If not, is it also achieved in Dynamic mode? It clearly isn’t in N or A mode
D and R modes have same power output but in D there are torque limiters in the first few gears. More detailed info here, you may need to use Google translate.

 

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I just tried it and there is a definite change in Race like the gear is engaging in Race as OP described
Transmission stays engaged and something else happens that increases engine load and causes it to build a bit of boost, even at idle. Could be as simple as closing the waste gates? If you datalog you can immediately see the boost change slightly while idling and switching to race. As well as the EGT and load rise a bit.
 

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Discussion Starter #15
For me, this post explains a lot. It explains also why if I creep along and try to make the slowest stop possible (I literally do mean the slowest and smoothest you can imagine) in all modes but R (not using manual shift) it feels like the car is being tapped on the bumper as you almost come to a stop, it’s the transmission going into this mode. It’s far easier to come to a smooth stop in race mode, although obviously and ironically it’s the completely wrong mode for such driving.
I think a lot of complaints about how hard it is to smoothly stop the car aren’t so much about the brake by wire, it’s more about the transmission and what mode you’re in.

the weird thing is that I have driven and owned ofter modern ZF 8 speeds and this difference is so much more profound in the qv. My wife has an Audi q7 with a ZF and while it’s obviously a different variant, you’d never detect this behavior in that car. Is it just about how aggressive the shifting is programmed or what else explains it? The ZF 8 speed is so wide spread, and for many drivers on different cars this disturbance in the smoothness would result in constant trips to the dealer to complain, yet it doesn’t, so what different about the qv In this regard? If this happened in a bmw 7 or Rolls Royce with the ZF, the car would be back at the dealer every week.
 

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the weird thing is that I have driven and owned ofter modern ZF 8 speeds and this difference is so much more profound in the qv. My wife has an Audi q7 with a ZF and while it’s obviously a different variant, you’d never detect this behavior in that car. Is it just about how aggressive the shifting is programmed or what else explains it? The ZF 8 speed is so wide spread, and for many drivers on different cars this disturbance in the smoothness would result in constant trips to the dealer to complain, yet it doesn’t, so what different about the qv In this regard? If this happened in a bmw 7 or Rolls Royce with the ZF, the car would be back at the dealer every week.
ZF supplies the units but each OEM will provide their own software for the unit.... so how it behaves is ultimately up to the OEM in which it is installed...so an 8HP75 in an Alfa may behave completely differently than an 8HP75 in a BMW or another vehicle
 

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Discussion Starter #17
ZF supplies the units but each OEM will provide their own software for the unit.... so how it behaves is ultimately up to the OEM in which it is installed...so an 8HP75 in an Alfa may behave completely differently than an 8HP75 in a BMW or another vehicle
Sure, but wouldn’t the other manufacturers be using the fuel saving advantages afforded by the ‘neutral shifting‘ (or whatever its best to name it)? If so, why doesn’t it have the same clunkiness in other applications?
 

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Sure, but wouldn’t the other manufacturers be using the fuel saving advantages afforded by the ‘neutral shifting‘ (or whatever its best to name it)?
Thats a question for the other manufacturers...but to somewhat answer your question, sail mode and neutral at stops is not an Alfa exclusive..other OEM's also use it

If so, why doesn’t it have the same clunkiness in other applications?
I dont experience any "clunkiness" but again, its all software related.... you may want to get your software levels checked if you can find a dealer who will do it. There are incremental updates to the PCM an TCM ( and other modules too) that many cars never received
 

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Discussion Starter #19
Thats a question for the other manufacturers...but to somewhat answer your question, sail mode and neutral at stops is not an Alfa exclusive..other OEM's also use it



I dont experience any "clunkiness" but again, its all software related.... you may want to get your software levels checked if you can find a dealer who will do it. There are incremental updates to the PCM an TCM ( and other modules too) that many cars never received
maybe clunky is an exaggerated term, but there aren’t many people who describe the process of stopping a Guilia as “smooth“. I think we have to agree on that.
my point is that if other makers have the same transmission and use the same sail mode, why is that if you drive any other car with the same or similar transmission you‘d never detect this sail mode being used. How can it be so much different?

if it’s a programming issue thats already addressed by a tsb, that would be great, but I‘ll confirm it’s not when I go in for the 1yr maintenance next week
 

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maybe clunky is an exaggerated term, but there aren’t many people who describe the process of stopping a Guilia as “smooth“. I think we have to agree on that.
my point is that if other makers have the same transmission and use the same sail mode, why is that if you drive any other car with the same or similar transmission you‘d never detect this sail mode being used. How can it be so much different?

if it’s a programming issue thats already addressed by a tsb, that would be great, but I‘ll confirm it’s not when I go in for the 1yr maintenance next week
Yeah, there are smoother stopping cars for sure, but there have been many improvements and your car may not be running the most current software . Hopefully you can get it sorted and continue to love this car...:)
 
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