Ten gears seem like too many, but there's logic behind a 10-speed transmission. Jason Fenske of Engineering Explained discusses design factors and trade-offs that drivetrain engineers consider in the age of performance and efficiency.
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Why a 10-Speed Transmission Actually Makes Sense
- Thread starterboss302ls
- Start date
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You can keep the engine in its most productive range, which means less drop-off in acceleration with each upshift. As long as it's not hunting for gears constantly, and the shifts are FAST, more gears are better. Cost and packaging factors not included.
Well said! Many early 6-speed auto boxes were diabolical because the shifts were slow and the programming couldn't cope with a gradual roll-in on the throttle - they'd get lost in trying to figure out which gear to select, leaving the driver with no ability to accelerate. This indecisive dithering made my wife's 2008 BMW downright dangerous when merging onto a freeway, but her 2016 BMW with the 8-speed is excellent.
Absolutely. The importance of an effective transmission tuning/strategy increases with the number of gears added.
- Thread starter
- #5
Yep. That's another way of saying what Jason stated about trying to keep the transmission operating as close to the theoretical optimum peak power curve he showed. Another issue that should be considered is the time to shift from one gear to another. Jason mentioned the Lexus shifted in 120 milliseconds. I'd be willing to bet that this is the time to shift up and not downshift. I am not a drivetrain engineer but what little I know about the transmission downshift is that it is a little more complicated of a problem. I heard Tadge Juetter, who is the Chief Engineer for the Chevy Corvette, explain why downshifts in the A8 Corvette trans are much slower than the upshift. Downshifting is critical as if the wrong choice is made the car can lose control if too much torque is applied at the wrong time. The upshot of this is the power control module has a much more complex problem to solve. The algorithm within the firmware is more complex and will take longer to determine the proper shift and when it is ideal to shift. Keep in mind we are not talking seconds for this problem to be solved within the power control module, but it happens in milliseconds in using modern computers. A power control module (just a fancy name for a specific computer with firmware instructions) has to figure out what gear to shift up or down to. This determination could be different depending upon if you are in say a "track" mode or a sport mode or say comfort mode, etc. Faster computers mean faster shifts but drives software and hardware development costs up. Engineering is all about trade offs.
I haven’t seen this yet but I’m sure the 10 speed Auto is incredible. Hopefully it’s available on the GT500.
- Thread starter
- #7
Yep, I think that's what most insiders are saying. Should be one hell of a setup. I just wish Ford would once and for all-time get away from using plastic trim everywhere especially on their interiors. It really detracts from any car. I just can envision paying 70K+ for an vehicle with this stuff inside. How about using wood? Better for environment too and easy to work with. Sorry about rant.
The 2017+ Mustangs have upgraded door panels that make the interior much nicer.
- Thread starter
- #9
I wish Ford would make more use of leather (or leather constituents), or naugahyde, or wood trim. It can't be that expensive to do. I'm not asking for Porsche type luxury but I believe Ford could do a lot more than they are. Corvette did this when they introduced their generation C7 and this change improved their interiors significantly. Ford could offer an interior upgrade as an option package if the costs are the problem.
JDee
Ancient Racer
I wish Ford would make an interior downgrade option that gets rids of all the extraneous weight and sound deadening stuff, just a simple lightweight set of panels and carpet that cover up the bare steel and nothing more. My base is probably one of the lightest PPs Ford made, but it's still carrying far more weight than I'd like. Not quite ready yet for a gut job, but getting closer, I keep wondering how Dean gets those GT4s to 3100 lbs.
Must be tough for a company like Ford to try to be all things to all people.
Must be tough for a company like Ford to try to be all things to all people.
Norm Peterson
Corner Barstool Sitter
10 gears probably is too many for a conventional manual transmission; they're just too closely spaced to use them all in anything resembling normal daily driving, but might be a little too far apart to use only every other gear.
Norm
- Thread starter
- #13
I believe the Jason Fenske video was discussion limited to 10 speed automatics. I would agree 10 speeds are a bit much for a manual trans but then again semi-trucks have 18 gears. I wonder why semis do not have automatics in them.
Norm Peterson
Corner Barstool Sitter
I know what you mean. If it's the 'driving' part that really does mean the most, even the '08 interior can be entirely satisfactory - minus any bright interior trim of course. Hell, once I've found the slot to put the key in to start it, I don't even notice the interior in terms of aesthetic quality.
Norm
Norm Peterson
Corner Barstool Sitter
Some already do.
But the majority of 18-wheeler transmissions use a splitter arrangement of some sort (I don't really know how that works). My son drives a Kenworth and recently swapped a 13-speed in where I think he'd had a 10. Basic steps between the gears are around 1.4 to 1.0, except that the upper 4 are also split with ratios midway between being available giving about 1.2 to 1.0 if you need it. He thought briefly about an 18-speed, but I guess unless you're frequently hauling overweight loads or mostly driving in the mountains, having 18 is not really necessary.
It's crossed my mind that the 10R80 minus all of the automatic shift logic, with full shift lever control over P, R, N, and +/- or other control over forward gear changing might be an interesting new take on the AT vs MT matter.
Norm
- Thread starter
- #16
In last month's June issue of Motor Trend magazine, their editors reviewed Ford's 18 Mustang interior. It looks like Ford is really working to improve their interiors. They've come a long way in the past 5 years. Take a look:
https://www.motortrend.com/cars/ford/mustang/2018/2018-ford-mustang-gt-interior-review/
https://www.motortrend.com/cars/ford/mustang/2018/2018-ford-mustang-gt-interior-review/
JDee
Ancient Racer
Only some transmissions use a splitter and it's only on the upper range, at least it was when I was a long haul trucker back in the late 80s - early 90s. There's all kinds of different big truck transmissions, 9 and 10 speeds were basic and most cheaper trucks had them, that's 2 ranges with 5 gears, two separate shifters for gear and range. I never drove a 9 speed so no idea how that worked.
The other ones I drove were 15 speed, which was 3 ranges and 5 gears, the 1st range was deep reduction, topped out at about 5 mph in 5th. For any US legal loads nobody used the first range, only in Canada where we can haul 165,000 lbs is it useful, US loads used to be 88,000 lbs max and no need for that deep reduction gear.
Then there was the much loved "13 over", that's the one with the splitter on the 4 gears in high range. So 2 ranges and when in high range you can split each gear. The splitter was air powered, it was a pre-selector and all you had to do to shift it was flick the splitter switch, lift smoothly off the fuel and then come back on the fuel, either harder or softer depending on whether you were going up or down on the split. The air splitter did the shift in that tiny millisecond during the rev change when there was no load on the gears. It was a very nice gearbox for long haul US legal loads and my favorite by far, that's probably what your son has now and I bet he likes it a lot.
Lots of automatics in big trucks now because they have a hard time finding people who can master clutchless shifting. In a big truck you used the clutch to get away from a dead stop, after that you never touch it. Or you double clutch which looks really silly, guy sitting there pumping like a madman on the clutch is comical and it is a lot of needless work. It's far easier to shift without the clutch in a big truck than it is in a car like ours due to the size of the gears involved.
Boy that takes me back a lot of years and several careers! I don't envy your son now driving a big rig in the traffic we have these days, that's a rough go.
Norm Peterson
Corner Barstool Sitter
That description sure sounds like that's what he has. He sent me a .pdf that mentions Eaton, Fuller, and Roadranger.
A sad commentary . . .
Norm
JDee, They could have used you in those "Bandit" movies! You missed your calling...
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JDee
Ancient Racer
LOL! Well, I still have the bandit 'stache, but it's got a lot of grey in it these days! I really did enjoy driving big trucks, as long as I was not doing P & D in cities, that's no place for a long nose Pete highway tractor. It was a good living and I saw a lot of country but it's a lot tougher for those guys now on all levels.
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