7A Transmission...dare I commit heresy?

brucelidat · 12-11-2011, 12:53 AM

Quote:

Originally Posted by wstar

In particular, aside from (beginner-mode, imho) tracking my 7AT, I also come from a background of driving a stick (6-speed LS1, in a '99 Trans Am actually) for about a decade before I switched to the 7AT. My shifting necessity/habits haven't changed at all: I drive my 7AT in M-mode always, so I'm always picking my gear like I was used to doing driving manual.

To me, the main downside of crappy/traditional autos is just not being able to tell the car what gear you want to be in. The car *cannot know* what the appropriate gear is. A traditional auto only really has 3 inputs to its gear selection algorithm: RPM, Accel Pedal Position, and Current Speed. None of those account for all of the other factors that go into a manual gearing decision, most of which have to do with seeing/knowing what's on the road in front of you and knowing what you plan to do about it.

With an AT like our 7AT though, that factor's gone. You get to control the gearing all the time. And in that rare sacrilegious moment when you decide you just have to eat a burger in the car while driving somewhere, or let some chick drive your drunk *** home, you can flip it to D and act like a grandma.

All in all, I love the 7AT. As jnaut said: get a cooler on it before doing anything serious. Also, ignore the fact that the Service Manual says the fluid doesn't need to be replaced for life. I'd replace it every 20K miles or so on the street, or more often tracking.

It's not perfect, it's not a DSG/PDK -type thing, but for the price range it's a damn fine compromise and performs well IMHO.

Are you saying to get a cooler for the transmission? I am going to a track day next weekend and no one has mentioned a cooler for the tranny. How important is this? Also, I thought the tranny was sealed. How do you change the fluid?

wstar · 12-11-2011, 12:14 PM

Quote:

Originally Posted by brucelidat

Are you saying to get a cooler for the transmission? I am going to a track day next weekend and no one has mentioned a cooler for the tranny. How important is this? Also, I thought the tranny was sealed. How do you change the fluid?

You *can* do a track day without an AT cooler, esp if it's one of your first. Just be cognizant of not overheating it too much. If you're only doing 10-15 minute sessions of balls-out driving and getting some cooldown in-between, it will probably ok, especially in winter weather. You'll know it when it starts getting too hot. It will start performing crappier (slower shifts, etc), you'll feel it.

As far as fluid changes go: from a factory service manual perspective, it's supposed to be "maintenance-free" for the consumer. So they don't provide a dipstick for checking the level, or any sort of easy filler tube either. There are procedures for checking fluid level and draining/filling, but the draining and filling is done via drain-fill plugs on the transmission body itself (much like with a manual or a differential).

The correct fill level, as with most things of this nature, is when it barely seeps out of the fill hole. However, to get the factory-correct fill amount, you have to check this with the internal temperature of the 7AT in a very specific range. The TCM knows this temperature, but only Dealership tools can read the temperature to know the fill is correct. That's the reason that, generally speaking, only the Dealership can deal with fluid checks/changes.

In practice, you should probably get the fluid swapped every ~20K miles for a hard-driven and/or lightly-tracked car, IMHO. The easiest and most reliable way to do it at this time is to have a dealership do it for you. Just make sure they don't just send some random tech to do a "standard" transmission flush. Be sure they've read the 370Z service manual and understand about the filling procedures and checking Consult-III temps, otherwise they're doing no better guesswork than you could in your garage.

Supposedly GTM was working out a set of instructions for us to reliably refill without a dealership. They probably developed a guideline based on spot-checking some point on the transmission's outer case with an IR thermometer. Never heard any more details on this though.

wstar · 12-07-2011, 01:44 PM

Quote:

Originally Posted by ImportConvert

So...

...what quirks about the 7A would tick me off? Throttle delay even worse than the "drive-by-wire" in use with 99% of cars now?

No, the throttle is just as responsive in M-mode on 7AT as it is on a manual.

Quote:

Delay on the freeway when stomping it in D? Not skipping gears when floored in 7th to a 3rd drop?

If you drive in D, it will shift down as far as it can given rev limits if you floor the pedal and hold it. There's always some pre-shift delay, but IMHO it's not really notable in the scenario.

Quote:

Shift flare? Sluggish shifting when cold? Overheating on track-days without an additional cooler?

I've had occasional shift flare on the 4->5 shift recently, but I think that had more to do with cold fluid and/or me experimenting with strange Torque Map settings for the 7AT in UpRev and/or perhaps I'm slightly underfilled on fluid. In any case 5, 6, and 7 are all overdrive gears anyways. You get into the low 120's mph at the top of 4th when you're on the throttle hard. I could see using maybe 5th on a very fast track on an NA 370, but never 6 or 7.

It does need to warm up a bit if it's cold out and/or the car is overnight cold before it shifts optimally. And it does need an additional cooler for serious track use.

Quote:

How does it feel in "manual"? You floor it and it's an instant connection like the stick, or the tq converter soaks up the "hit" and it feels sluggish from say, a 50mph punch compared to a manual?

It's a very instant connection just like a manual when it's in lockup mode (which is pretty much anytime you're not at extremely low revs, or not in the midst of a shift execution). For example, you can sit up around 4K RPM or whatever at maintenance throttle level and gently play the throttle up and down over the maintenance line and get very reactive feedback from the car shifting between slight accel and slight decel. And if you stomp it at that point, it's going to shoot off just like a manual would.

toxik · 12-07-2011, 06:12 PM

at ftw

LakeShow · 12-07-2011, 10:25 PM

Don't keep it and D and wait for the car to downshift for you, there are paddles there for a reason.

wstar · 12-08-2011, 12:20 AM

Re: Osiris tweaks to the 7AT Torque Map: IMHO you should really only do that to adjust for engine torque, and even then on NA we're talking +10-15% over stock values at most. The guideline is to monitor slip under what should be lockup conditions (slip meaning RPMs vs wheel speed isn't stable), and tune the torque values just high enough to reliably kill slip.

When you set them massively higher than they need to be, it does exactly as you describe: every time you click the button it slams everything and kicks you in the butt. You're just causing excess wear all over your drivetrain, and more importantly for track stuff, you're upsetting the balance of the car. The last thing you want while upshifting out of a corner and still pushing to the side a bit is to suddenly shock the drivetrain and rear wheels. It may feel "faster", but the quick, smooth engage at a lower torque map value is better.

Mecinoid · 12-08-2011, 01:19 AM

Quote:

Originally Posted by wstar

Re: Osiris tweaks to the 7AT Torque Map: IMHO you should really only do that to adjust for engine torque, and even then on NA we're talking +10-15% over stock values at most. The guideline is to monitor slip under what should be lockup conditions (slip meaning RPMs vs wheel speed isn't stable), and tune the torque values just high enough to reliably kill slip.

When you set them massively higher than they need to be, it does exactly as you describe: every time you click the button it slams everything and kicks you in the butt. You're just causing excess wear all over your drivetrain, and more importantly for track stuff, you're upsetting the balance of the car. The last thing you want while upshifting out of a corner and still pushing to the side a bit is to suddenly shock the drivetrain and rear wheels. It may feel "faster", but the quick, smooth engage at a lower torque map value is better.

Your right on as far as I can tell ... You should just leave the program alone and let it adapt... You want to beat on the car racing but, you don't want to break anything. Been there and done that with modified shift programs on autos before. Plus, I believe in stock mode the little bit of slip you get on engagement in the corners helps you from sliding around in VDC off mode. Most of you guys wouldn't think about upshifting a manual half way through a corner. Very nice how that all works...

Jordo! · 12-08-2011, 04:49 AM

Quote:

Originally Posted by wstar

Re: Osiris tweaks to the 7AT Torque Map: IMHO you should really only do that to adjust for engine torque, and even then on NA we're talking +10-15% over stock values at most. The guideline is to monitor slip under what should be lockup conditions (slip meaning RPMs vs wheel speed isn't stable), and tune the torque values just high enough to reliably kill slip.

When you set them massively higher than they need to be, it does exactly as you describe: every time you click the button it slams everything and kicks you in the butt. You're just causing excess wear all over your drivetrain, and more importantly for track stuff, you're upsetting the balance of the car. The last thing you want while upshifting out of a corner and still pushing to the side a bit is to suddenly shock the drivetrain and rear wheels. It may feel "faster", but the quick, smooth engage at a lower torque map value is better.

If memory serves, I've got it around 25-30% higher across the board after about 1.5K, and it is definitely much faster off the line. 3-4 can be a bit rough, and could potentially upset the chassis if you aren't careful, but I found that a gentle relaxing of throttle input on the shift will cause it to read a slightly lower load value, and soften the shift without losing engine speed or road speed.

That said, I imagine a slightly lower setting would be a good compromise for optimal straight line driving and cornering. Feels good to me as is -- but it's definitely something that would have to be experimented with by anyone tracking the car to get it just right. I think for a road car you can have it set be a bit more aggressively safely.

Also, the faster shifts should put less wear on the clutch bands, while only marginally increasing shock to hard parts. Overall, you probably break about even in overall wear and tear.

wstar · 12-08-2011, 12:22 AM

Re: throttle tuning, see here: Smooth Throttle for UpRev

Mecinoid · 12-08-2011, 01:12 AM

Here's the thing you guys are missing... see bold:

The 370Z’s 7-speed automatic with Downshift Rev Matching (DRM) and Adaptive Shift Control (ASC) is designed to offer quick, manual-like shifting when operated in manual mode with a target time of 0.5 seconds between shifts. Drivers can use the standard paddle shifters or the shift lever. With optimized torque converter lock-up logic, the 7-speed automatic feels very direct, like a manual transmission. The 7-speed’s wide gear ratios offer improved fuel efficiency (versus a 5-speed automatic), while the Adaptive Shift Control is designed to adjust to the driver’s driving style.

You have to drive the car in the mode you want it to perform in for a while. Then, it shifts like you wouldn't believe. I'm sold on the S7 tranny. Even double downshifts come easily if you know what speed you can do them at. No over reving here. Remember it's a little different for a six speed because it shifts very fast through the gears at bottom end to get you going. If you tromp on it and hold it to 7K then shift it shoot you out of the slot like no other. I am truly impressed and I have driven only stick shifts in my sports cars to this point. Back in 2004 I tried the auto in a Z and G and it was way sluggish. This is a completely different beast. Give it time to adapt to your driving style, then let me know what you think. It takes about 20-30mins to adapt as far as I can tell. That is driving through tight twisties.... Then it is a completely different car. 10 mins back in auto mode the car drives like your mom's car.

I'm loving the S7 more and more each day. I always win the stop light battle to the freeway on ramp... By the time I hit the on ramp they are just a spec in my mirror and I have to start looking for the officer because I'm going way too fast.

I have to be careful or this car is going to get me a lot of tickets. It's just too fun to rev to 7K so that I can feel that hard shift into second. At that point, I'm over 60mph and in trouble already...

Enjoy the ride !!! AJ on his seventh Z car now.

ImportConvert · 12-08-2011, 03:11 PM

Quote:

Originally Posted by Mecinoid

Here's the thing you guys are missing... see bold:

The 370Z’s 7-speed automatic with Downshift Rev Matching (DRM) and Adaptive Shift Control (ASC) is designed to offer quick, manual-like shifting when operated in manual mode with a target time of 0.5 seconds between shifts. Drivers can use the standard paddle shifters or the shift lever. With optimized torque converter lock-up logic, the 7-speed automatic feels very direct, like a manual transmission. The 7-speed’s wide gear ratios offer improved fuel efficiency (versus a 5-speed automatic), while the Adaptive Shift Control is designed to adjust to the driver’s driving style.

You have to drive the car in the mode you want it to perform in for a while. Then, it shifts like you wouldn't believe. I'm sold on the S7 tranny. Even double downshifts come easily if you know what speed you can do them at. No over reving here. Remember it's a little different for a six speed because it shifts very fast through the gears at bottom end to get you going. If you tromp on it and hold it to 7K then shift it shoot you out of the slot like no other. I am truly impressed and I have driven only stick shifts in my sports cars to this point. Back in 2004 I tried the auto in a Z and G and it was way sluggish. This is a completely different beast. Give it time to adapt to your driving style, then let me know what you think. It takes about 20-30mins to adapt as far as I can tell. That is driving through tight twisties.... Then it is a completely different car. 10 mins back in auto mode the car drives like your mom's car.

I'm loving the S7 more and more each day. I always win the stop light battle to the freeway on ramp... By the time I hit the on ramp they are just a spec in my mirror and I have to start looking for the officer because I'm going way too fast.

I have to be careful or this car is going to get me a lot of tickets. It's just too fun to rev to 7K so that I can feel that hard shift into second. At that point, I'm over 60mph and in trouble already...

Enjoy the ride !!! AJ on his seventh Z car now.

I did not take the adaptive nature into account at all.

Also read about temp above your post, sounds like it won't matter one bit to me. I won't overheating it.

I'm kindof torn, but the reason is all the bad I hear about the manuals vs. The disconnect I have always felt with automatics. I'm still in the manual camp, but if they find the car I want except in auto, ill be stressing.

UNKNOWN_370 · 12-08-2011, 11:55 PM

Quote:

Originally Posted by ImportConvert

I did not take the adaptive nature into account at all.

Also read about temp above your post, sounds like it won't matter one bit to me. I won't overheating it.

I'm kindof torn, but the reason is all the bad I hear about the manuals vs. The disconnect I have always felt with automatics. I'm still in the manual camp, but if they find the car I want except in auto, ill be stressing.

Import, Mecanoid could not have put it any better. The at takes time to really understand its capability. Early in the thread red posted wwjd's review. I personally can downshift while decelerating or accelerating. And I'm not sure about what he meant about NOT being able to shift in turns but I don't shift until I am in a position to launch out of a turn. The 7at is incredible. From my standpoint, you lose out on 3 things.
1. The ability to burnout
2. Exhaust note is less aggressive than the manual/very mild torque converter drone. But nothing close to how bad other autos have it.
3. If you are really used to the clutch, you will feel like you need something to step on with your left leg at first. I have driven every shifting auto out there in the Z's price range and above. Nothing feels like it except the DCT's out there.

I'm not telling you to buy the auto. And I'm not going to say the auto is better than a manual. But I will say this. It will be a long time till another car brand will be able to duplicate this level of performance from a slushbox. When people are in my car and I'm shifting. They think its a manual transmission. Power delivery from the auto is that direct. I will take the pepsi challenge on power delivery with the 7at. Its just that impressive.

Obviously there will be advantages to a manual on a few levels.
Turbos bigger than stage 2. Drifting is easier. The art of heal and toe when SRM is off. But the 7 at provides so much diversity in its programming. I thing it makes it easy to transition from manual to auto.

Skeeterbop · 12-08-2011, 03:27 PM

Here is another reason to get a manual

: Not only are manual transmissions awesome, they're a theft deterrent

Guard Dad · 12-08-2011, 04:12 PM

Took a two hour mountain drive with my 7AT yesterday:

I was smoother and more accurate with the steering-two hands on the wheel.
I was able to concentrate on the next corner better.
No missed shifts.
Effortless up and down shifts in mid corner.
Down shifts don't upset the car in mid corner.
I was a faster and probably safer driver due to fewer distractions.

Other bonuses:

Easier in traffic.
Better gas mileage.
Quicker.
More gears to choose from.
Quicker down shifts than a manual if traffic surprises you and you need power right now- stomp on it and go.
Better trade-in.
The shifts are faster than you think.

Negatives:

It's direct but not as direct as a manual.
The manual involves you more.
Manual is more "raw".
A manual is cheaper to buy.

I've always preferred manuals but an occasional issue with my left leg made me give the 7AT a look. From time to time I wish I had a manual but I keep finding more ways to exploit the advantages of the 7AT so I'm happy with my choice.

Get what YOU want.

ImportConvert · 12-08-2011, 05:33 PM

Wait...other poster said it locks shifts out in corners... Which is it? See page one, first reply. I'm on my cell or I would link and quote.

12-07-2011, 10:25 PM	#5 (permalink)
LakeShow A True Z Fanatic Join Date: Dec 2010 Location: L.I., NY Posts: 5,307 Drives: Everything Rep Power: 26	Don't keep it and D and wait for the car to downshift for you, there are paddles there for a reason. __________________ \|2013 Audi S4\|Ibis White/Black\|S-Tronic P+\| \|2013 370z\|PearlWhite/Persimmon\|Touring/Sport/Nav\|F.I. CBE 18" CF\| \|Sold\|2011 370z\|Gun Metallic\|Touring/Sport/Nav\|

12-08-2011, 12:20 AM	#6 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3595	Re: Osiris tweaks to the 7AT Torque Map: IMHO you should really only do that to adjust for engine torque, and even then on NA we're talking +10-15% over stock values at most. The guideline is to monitor slip under what should be lockup conditions (slip meaning RPMs vs wheel speed isn't stable), and tune the torque values just high enough to reliably kill slip. When you set them massively higher than they need to be, it does exactly as you describe: every time you click the button it slams everything and kicks you in the butt. You're just causing excess wear all over your drivetrain, and more importantly for track stuff, you're upsetting the balance of the car. The last thing you want while upshifting out of a corner and still pushing to the side a bit is to suddenly shock the drivetrain and rear wheels. It may feel "faster", but the quick, smooth engage at a lower torque map value is better. __________________ 7AT Track Car! Journal thread / Car setup details

12-08-2011, 12:22 AM	#9 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3595	Re: throttle tuning, see here: Smooth Throttle for UpRev __________________ 7AT Track Car! Journal thread / Car setup details

12-08-2011, 01:12 AM	#10 (permalink)
Mecinoid Base Member Join Date: Sep 2011 Location: Discovery Bay Posts: 234 Drives: 16 370Z Sport Wht S7 Rep Power: 6725	Here's the thing you guys are missing... see bold: The 370Z’s 7-speed automatic with Downshift Rev Matching (DRM) and Adaptive Shift Control (ASC) is designed to offer quick, manual-like shifting when operated in manual mode with a target time of 0.5 seconds between shifts. Drivers can use the standard paddle shifters or the shift lever. With optimized torque converter lock-up logic, the 7-speed automatic feels very direct, like a manual transmission. The 7-speed’s wide gear ratios offer improved fuel efficiency (versus a 5-speed automatic), while the Adaptive Shift Control is designed to adjust to the driver’s driving style. You have to drive the car in the mode you want it to perform in for a while. Then, it shifts like you wouldn't believe. I'm sold on the S7 tranny. Even double downshifts come easily if you know what speed you can do them at. No over reving here. Remember it's a little different for a six speed because it shifts very fast through the gears at bottom end to get you going. If you tromp on it and hold it to 7K then shift it shoot you out of the slot like no other. I am truly impressed and I have driven only stick shifts in my sports cars to this point. Back in 2004 I tried the auto in a Z and G and it was way sluggish. This is a completely different beast. Give it time to adapt to your driving style, then let me know what you think. It takes about 20-30mins to adapt as far as I can tell. That is driving through tight twisties.... Then it is a completely different car. 10 mins back in auto mode the car drives like your mom's car. I'm loving the S7 more and more each day. I always win the stop light battle to the freeway on ramp... By the time I hit the on ramp they are just a spec in my mirror and I have to start looking for the officer because I'm going way too fast. I have to be careful or this car is going to get me a lot of tickets. It's just too fun to rev to 7K so that I can feel that hard shift into second. At that point, I'm over 60mph and in trouble already... Enjoy the ride !!! AJ on his seventh Z car now. Last edited by Mecinoid; 12-08-2011 at 01:15 AM.

12-08-2011, 03:27 PM	#13 (permalink)
Skeeterbop A True Z Fanatic Join Date: Jan 2011 Location: Fort Bliss, TX Age: 41 Posts: 1,440 Drives: 2011 GM 370 base SP Rep Power: 17	Here is another reason to get a manual : Not only are manual transmissions awesome, they're a theft deterrent __________________ Srenity: "Yeah no rest needed to spread the love when your 20 that's for sure...."

12-08-2011, 04:12 PM	#14 (permalink)
Guard Dad Enthusiast Member Join Date: Aug 2010 Location: South Orange County, CA Posts: 422 Drives: 2010 370Z Silver A7 Rep Power: 15	Took a two hour mountain drive with my 7AT yesterday: I was smoother and more accurate with the steering-two hands on the wheel. I was able to concentrate on the next corner better. No missed shifts. Effortless up and down shifts in mid corner. Down shifts don't upset the car in mid corner. I was a faster and probably safer driver due to fewer distractions. Other bonuses: Easier in traffic. Better gas mileage. Quicker. More gears to choose from. Quicker down shifts than a manual if traffic surprises you and you need power right now- stomp on it and go. Better trade-in. The shifts are faster than you think. Negatives: It's direct but not as direct as a manual. The manual involves you more. Manual is more "raw". A manual is cheaper to buy. I've always preferred manuals but an occasional issue with my left leg made me give the 7AT a look. From time to time I wish I had a manual but I keep finding more ways to exploit the advantages of the 7AT so I'm happy with my choice. Get what YOU want.

12-08-2011, 05:33 PM	#15 (permalink)
ImportConvert A True Z Fanatic Join Date: Jun 2010 Location: SWMO Posts: 4,454 Drives: 2019 CX5 GT Reserve Rep Power: 7627	Wait...other poster said it locks shifts out in corners... Which is it? See page one, first reply. I'm on my cell or I would link and quote.

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