Mostly city driving is the Skyactiv AT a concern?

[lizpat]

If you do mostly city driving, would the Mazda SkyActiv automatic transmission (clutch-based) be a concern as far as durability is concerned?

Here is what I understand about the SkyActiv AT:

At speeds below 5 mph, the torque converter is used. Above 5 mph, the clutch engages and locks in. In city driving, the clutch has to constantly engage, disengage. Is this accurate? If so, wouldn't this mean a much shorter effective life for the transmission? A new transmission at that, replacement or repair would be very expensive.

 

[KrisZ]

If you drive smooth, i.e. no treating the gas and brake pedals as if they were ON/OFF switches, I don't see any issues. If the tranny was designed to lock the TQ often, then there is probably more clutch material just for that. Also once the TQ is locked above 5mph, it doesn't unlock and lock again during gear changes, unlike a DSG.
I would probably just change the ATF more often and call it a day.

 

[dparm]

I'm sure Mazda has thought of that -- tons of people use their cars in stop-and-go traffic every day. Replacing a clutch is much cheaper than replacing an entire transmission.

 

[Ram01]

The will wear out faster with the stop and go. Just purchase an extended warranty and use synthetic AT fluids. Hope for the best

 

[lizpat]

Originally Posted By: KrisZ
If you drive smooth, i.e. no treating the gas and brake pedals as if they were ON/OFF switches, I don't see any issues. If the tranny was designed to lock the TQ often, then there is probably more clutch material just for that. Also once the TQ is locked above 5mph, it doesn't unlock and lock again during gear changes, unlike a DSG.
I would probably just change the ATF more often and call it a day.


If it doesn't unlock and lock again for gear changes, then I think this changes the story. Good to hear.

 

[bigjl]

As Mazda and Ford have been sharing tech for a while is it possible this is the Powershift box as fitted to Volvo and Ford vehicles?

If so i didn't think any of these double clutch autos had a torque converter.

I did about 15/20k in a Ford Galaxy with one of these boxes back in '12.

There was a common issue of slight judder when taking up drive with a little bit of steering lock on but otber than that it was a great box to use round London.

I felt it could be jerky if you were harsh with the throlle in slow moving traffic.

So i tended to drive it like a manual rather than just give it a bootfull like you would do in a TQ autobox.

Drive take up is pretty much instantaneous.
Fuel economy, real world, savings of 10mpg seemed typical between the 2010 Galaxy's with a traditional torque converter auto and the Powershift box.

The company whose vehicle it was have a fleet of 4000 of these. As the fleet is changed every 3 years it is likely the more than 2/3s are now Powershift type boxes.

 

[bigjl]

Sorry.

Forgot durability.

Apart from the juddering i mentioned they are robust.

Each vehicle covering 40/50k a year per year round London. Not driven by owners drivers. All leased to the drivers so hammered.

Some of the 1st are now on well north of 100k miles.

The data obtained from these vehicles is fed back to the Ford R&D department in Essex. This info has already been used to produce software updates to improve drivability apparently.

Haven't seen an engineering disgram of this transmission but the lack of a TQ is the information i hsve been given

 

[Rand]

I thought that mazda didnt share with ford anymore?

are you saying the mazda "skyactive" AT has an equivalent at ford?

or was those last few posts just a bunch of off topic?

 

[bourne]

Mazda and Ford are separate companies. Skyactiv is Mazda's own project sans involvement from Ford. The Skyactiv transmission will be ok in the city, it will still start off with a fluid coupling allowing for slip before going into full lock up mode. Full lock up mode is actually better for reliability since there is no "slip" hence no generation of heat from friction. Also they have tuned the throttle to be really lazy at take off, allowing for a smoother driving experience. You dont really feel how crisp the transmission really is till you are really getting on it.

 

[dparm]

BTW Lexus has been doing this with the Aisin-sourced 8-speed in many of their cars for several years now. The LS460 has it, as does the IS F and new IS 350.

 

[SwampSurvivor]

This is not a dual clutch transmission and it is not related to anything in Volvos.

It's simply a 6 speed torque converter automatic with the torque converter clutch locked above 5 MPH.

 

[Eddie]

The SkyActive AT also locks into all? the forward gears I've read. I was concerned myself but, bought one anyways based on my previous experience with Mazda engineering. Ed

 

[dparm]

Originally Posted By: Eddie
The SkyActive AT also locks into all? the forward gears I've read. I was concerned myself but, bought one anyways based on my previous experience with Mazda engineering. Ed


2nd gear and up. 1st gear isn't locked so you get a smooth takeoff from a stop and maximum torque multiplication.

 

[bigjl]

So a complete new development

And not a double clutch auto

The above post relates to anybody buying a Ford Powershift though.

So may be of help to somebody

No news of this new AT in UK

Could be they are gradually moving out of the UK market then

They certainly don't sell much here

 

[badtlc]

As has been said, Skyactiv-AT is NOT a dual clutch transmission. It has a torque converter, not a clutch.

 

[Eddie]

Theremust be a time interval before the AT locks up in any gear. If one is accelerating normally, then I suspect there is no lockup until a steady speed if reached after some seconds so it is not continuing to lock & unlock ever few Milli seconds. Ed

 

[badtlc]

Originally Posted By: Eddie
Theremust be a time interval before the AT locks up in any gear. If one is accelerating normally, then I suspect there is no lockup until a steady speed if reached after some seconds so it is not continuing to lock & unlock ever few Milli seconds. Ed


You would probably be interested in reading this:
http://www.mazda.com/mazdaspirit/skyactiv/transmission/skyactiv-drive.html

 

[SteveSRT8]

Many modern slushboxes use fully variable TC lock up throughout most forward gears. My car from 05 has infinitely variable lockup in the top 4 gears.

This has been around since very early in the new Millenium. It is by no means anything new at all.

Note that GM holds a patent on TC lockup mgmt involving an algorithm that locks and unlocks the TC randomly across extremely short time frames (milliseconds) to avoid driveline vibrations.

It is many years old as well.

 

[John_in_Seattle]

I recently bought a SkyActiv 2014 Mazda 6, and I also bought a maintenance manual CD on Ebay to see what's really in the car I bought.

The drawing and description of the transmission seem to show that the SkyActiv AT is really a 6-speed, dual wet-clutch gearbox PLUS a torque converter.

The computer seems to lock up the torque converter except at really low speeds, where the TC provides some torque multiplication. Yes the SkyActiv AT has a TC; but having some fluid coupling is very useful to avoid startup and first-to-second shift shutter that I've experienced on some Fords. But, during most driving above 5-6 mph, the TC is locked up, and the AT has the efficiency of a dual-clutch transmission without any TC power loss. While the TC is locked up, the fluid just adds to the flex-plate rotational inertia.

I believe that this explains why, on the 2014 Mazda 6 specs, the AT get BETTER gas mileage than the MT. And it gets much better mileage than the earlier non-SkyActiv ATs. I just wonder why Mazda doesn't explain it that way.

 

[badtlc]

Originally Posted By: John_in_Seattle


I believe that this explains why, on the 2014 Mazda 6 specs, the AT get BETTER gas mileage than the MT. And it gets much better mileage than the earlier non-SkyActiv ATs. I just wonder why Mazda doesn't explain it that way.


That might be according to the EPA tests but the MTX blows the ATX out of the water in the real world.

Also, the 2014 Mazda3 has the same EPA ratings for ATX and MTX at 41 MPG. Nice to see them be more honest with the MTX numbers instead of pushing ATX sales. Just look at the drastic difference in the CX-5 numbers. They decided to push the MTX in order to advertise the most fuel efficient cSUV.