2014 ATS With a CVT (drive system)

[winterset]

I bought this car for my teen daughter back in 2014.  I recently learned i had run flats, now today i found out it has a cvt (basically a belt driven constant velocity transmission).  I only drove the car once or twice, and i didn't notice anything different than other cars i have driven over the years.  Anyone have any opinions on these setups?  Yes, i guess cadillacs are always full of surprises.  

[Bruce Nunnally]

That surprises me -- what are the transmission codes?  I would have said that Cadillac has not offered a CVT on the ATS.  The spec sheet suggests these two:

 

Transmissions

	TREMEC TR3160	Hydra-Matic 6L45
Type:	fully synchronized six-speed manual with single overdrive	six-speed, electronically controlled, automatic overdrive with torque converter clutch
Gear ratios (:1):
First:	4.12	4.06
Second:	2.62	2.37
Third:	1.81	1.55
Fourth:	1.30	1.16
Fifth:	1.00	0.85
Sixth:	0.80	0.67
Reverse:	3.75	3.20
Final drive ratio:	3.27 (2.0L)	3.27 (2.0L, 3.6L) 3.45 (2.5L)

[Cadillac Jim]

I have a friend with a Toyota sport-ute.  I don't know the model or engine, but it seems to drive much like the other cars with more than four or five gears in the transmission.  I was intrigued at the time and looked up the CVTs on the WWW and found that there are several out there and they don't have any disadvantages except that the CVT internal mechanism can't handle a lot of torque and it is used only on small engines.  Toyota uses them primarily on 1.6 liter and smaller engines, but they do have one line of automatic transmissions that they use on engines up to 2.5 liter.

Reference on Toyota CVT's (looks like it was written as an ad and transcribed to Wikipedia; they hate that):

https://en.wikipedia.org/wiki/Toyota_K_CVT_transmission#K411

A better article that treats all makes and types of CVT his here:

https://en.wikipedia.org/wiki/Continuously_variable_transmission

Advantages include better fuel economy and smaller size than conventional transmissions, disadvantages include low torque handling that limits them to small engines and street use.

I don't think anyone has a CVT that can handle anything near the power levels of the Cadillac 2.0T.  With the driveability and economy levels that they achieve with six and eight speed automatic transmissions, there isn't a lot of reason to try to build a CVT for the 2.0T or 3.6 DI.

The Cadillac 2.0T is not just a two-liter with a turbo.  It's designed from the ground up as a 250 to 275 hp engine, with internal cooling to match including sodium-cooled valves, direct injection, twin-scroll turbocharger to eliminate turbo lag and give plenty of low RPM torque, so it's really a successor to the VIN "Y" Northstar.  See the dyno chart here:

For 2015 and later, they have improved the torque from 260 lb-ft to 295 lb-ft.  I drove one in a loaner a few months back and it has plenty of guts and throttle response at highway speeds.

I have the GM factory shop manuals for every model for the model years 2002 through 2012 on a DVD, so I looked at the 2012 Aveo, and it has one automatic 6-speed and several manual transmissions that were sold with it but no CVT.  I did a global search on the DVD with just "CVT" and got zero hits.  As far as I can tell, GM hasn't used a CVT in any of their cars, including the ones that have engines and transmissions that are made buy other manufacturers like Suzuki or Isuzu, at least through 2012.

Whoops, I did more looking and it turns out that GM did use a CVT in the 2002-2005 time frame in the Saturn Vue/Ion and the Opel Vectra.  I don't think that they had very good luck with it, from the Wikipedia article:

https://en.wikipedia.org/wiki/VTi_transmission

[rockfangd]

I would imagine you would know if it had a CVT. CVTs dont shift. They just go.

So if you drove a normal shifting vehicle and then drove a CVT equipped it would be very different.

That is my opinion

[Cadillac Jim]

At very light throttle, the eight-speed shifts are almost imperceptible.  But a quarter-throttle takeoff when the light turns green in a 50 mph zone will definitely have a noticeable couple of shifts.  You can also feel the 8-7-6 shifts at highway speeds when you give it a little throttle.

Note the amazing flat torque curve in the earlier post.  The PCM uses the eight-speed to keep the car between 1500 and 2200 RPM in most normal driving.

[BodybyFisher]

Here is an interesting demonstration of the CVT, from a Saturn.  I forget what it was that I have seen that used this technique it might have been a go cart.  If anyone knows why this youtube video does not embed itself let me know, I am posting from an android

https://www.youtube.com/shared?ci=hPUPUM27LiU

[winterset]

I will be honest.  I do not know now if my daughters 2014 ATS 2.0T AWD has cvt or not.

Took another drive down to florida to visit my parents (took minivan with 6 of us)

while we are away ATS is in the dealer getting minor paintless dent removal, and the backup camera and a cleaning).  I will check build codes when i am back.  

Thanks Jim and BBF for the info.  Somewhere i read that the 2.0T was supposed to be the replacement for the N* 

[Bruce Nunnally]

I would say the 3.6L V6 replaced the Northstar, as it evolved to make similar Hp/Torque as the V8.  Reviews of the STS with RWD Northstar V8 or V6 at the time suggested save money and get the V6.  There is a missing ultra V8 which is a V8 version of the current V6.  I think the TTV8 coming for the CT6 may be the first time that engine appears.  I expect it may be shared with the mid-engine Corvette / Cadillacs as well.

The 272hp/295 lb-ft torque 2L 4 is a nice powerplant.  I would like to see it tuned to 300+ hp but I think for Marketing that makes it too close to the V6 (which I think is the wrong way to think about it -- each powerplant should be tuned to max output!). 

The new LGW 3L TT at 400 hp vs the 3.6L LF3 TT at 420 hp or 3.6L LF4 TT at 464 hp confuses me.  Why not simply use the LF4 in everything? The 3L size must be an advantage in Chinese taxes:

China Passenger Car Tax Rates
Displacement	Current rate	Adjusted rate
≤1.0L	3%	1%
>1.0L, <2.0L	5%	5%
>2.0L, <3.0L	9%	9%
>3.0L, <4.0L	15%	25%
>4.0L	20%	40%

This is why the 2L I4 and the 3L V6 make sense.  That may also mean we see a 4L TT V8.

[Cadillac Jim]

In the Wikipedia article "List of GM Transmissions" the only CVT is the VTi, used on Saturn and Opel marques from 2002 through 2005 model years.

According to the article, GM has a deal with Ford to let Ford use the GM transverse transmission for FWD cars and GM will use the Ford 10-speed longitudinal transmission.  This has happened before.  In 1953, the Ford transmission plant burned down and they made a deal to use HydraMatics from GM until they got their plant back online.  The Lincoln that won the 1954 Mexican Road Race used a GM HydraMatic.

[Logan]

MMMmmm....hang on.....pretty sure it was GM that had the huge fire in 1953.

http://www.autotran.us/TheGreatHydraMaticFire.html

 

There are one or two current transmissions that GM and Ford developed together for cost savings. Would have to go look it up. 

 

[Cadillac Jim]

Yup.  I was young at the time and my memory did not serve me as well as usual this time.  Lincoln was already using Hydramatic transmissions and everybody had to find alternatives.  According to the article, Hudson, Kaiser and Nash had no alternatives, although the production output was available only nine weeks later, the first units going to Hudson, Kaiser and Nash.

[BodybyFisher]

16 hours ago, Logan said:

MMMmmm....hang on.....pretty sure it was GM that had the huge fire in 1953.

http://www.autotran.us/TheGreatHydraMaticFire.html

 

There are one or two current transmissions that GM and Ford developed together for cost savings. Would have to go look it up. 

 

You learn something new everyday.  I was a little over one month old at the time!  

I never heard of this fire and I never knew Ford used the Hydra-Matic, wow