So what happened to the rumors about GM's 8 speed double-clutch? Coming in 2015?
 

So we all read the rumors pre-announcement:

http://www.lsxtv.com/news/c7-corvett...-8-speed-auto/

"According to Motor Trend, GM has found itself in a bit of a bind regarding its next-generation transmissions for the upcoming 2014 C7 Corvette, among other vehicles. Their own in-house unit isn’t quite ready yet, so the General has outsourced the work to Aisin, a company owned in part by Toyota. It appears this delay only affects the automatic transmission, as other rumors indicate that GM has outsourced the 7-speed manual transmission to ZF.

Aisin makes two eight-speed automatic transmissions, including one capable of handling high torque loads for cars like the upcoming Corvette. More importantly though, GM needs to offer a smooth and efficient eight-speed automatic for its Cadillac brand. Other automakers like Mercedes and Chrysler already offer eight-speed automatics, so GM really needs to offer the same just to stay competitive."

I was pretty surprised when they announced a 6 speed auto to be honest... which leaves us in an interesting situation. Think we'll see the 8 on the 2015, or will they hold out for the Z06 and ZR1 models?

Oh, and hello from Camaro5 :)

I think it's a good possibility that an Auto box w/ greater than 6 forward gears will be on a future C7... if not '15 then soon after that. It's always about incremental or selective upgrades and improvements model year after model year. ;)

So, since Mercedes and Chrysler offer them, Chevrolet/GM must also offer an eight-speed transmission?

How is that logical?

First answer why a vehicle would need 8 forward speeds and then you'll understand why it's not an absolute necessity for the Corvette.

Eight-speed transmissions were developed to reduce road noise in high-end vehicles by keeping gearing within their engine's narrow power band that creates the most power without making excessive noise.

First off, the Corvette has a really wide power range, so you can put down the majority of the power without needing to shift repeatedly. And secondly, I'm pretty certain that Corvette drivers want to hear the engine as they stomp on the go-pedal.

So again, why does Chevrolet/GM ned to offer an 8-speed in the Corvette?

TBH I'm more excited about the double-clutch than the 8 speeds. I know more isn't always better, but it's documented GM is working on it so they must see some value in it.

Here's an earlier post on why GM went with the 6 speed auto:

8 speed transmission's on the way but trucks will probably get it first.

I'm not sure I understand the benefit of that many gears.

The purpose of multiple gears is to keep the engine at an rpm that is in the most efficient part of the torque curve.

If your engine is high revving then the torque curve is probably really narrow and you'll need to shift gears more times to keep it in that range. ;)

I really wish they gave it a dual clutch. Just as a reminder, the C6 used a 4 Speed auto for the first year or two.

It sounds like the 'Vette is torquey enough that it could do nicely with 3-4 gears for the LT-1. However, the increased number of gears would be more for fuel economy in the C7 application. Tadge's interview at the reveal has him saying a couple of interesting things - 1) they looked at an 8 speed auto but it wouldn't fit (Aisin or ZF sourced probably) and 2) that a DCT was considered but there wasn't an available unit which could handle the torque. He goes on to say that 6 gears is fine for the auto. Yet they added a 7th (3rd overdrive) on the manual :der:

could be a similar scenario here where the 8 speed isn't ready so they're going with the carryover box for the first year. Seems to be a popular theory on corvetteforum and, obviously, there's a precedent for it as well with the Vette now.

Exactly what I iterated earlier... in 2 models years or so, I think we may see A/T improvements whether dual-clutch, 8-spds, etc... I would think that Chevy's flagship will have to keep up with the Jones'es just because of competition or keeping up with the times even if it isn't absolutely required.

agreed

A dual-clutch automatic would likely smoke the manual, shaving a decent bit off the 0-60 time.

+1

Would have loved to see a dual clutch paddle system on the new Corvette. Hopefully it comes as an available option in later model years.

I'd love nothing more than to see one in the C7. Not holding my breath for now though. Although Ford has developed a dual clutch transmission in house (a rather crappy one as well) GM seems content to solider along with their current 6 speed slushbox and then release the anticipated 8 speed when ready. The C7 does have some packaging issues with the rearward located transmission AND serious torque numbers to deal with. Hence the truck/4X4 transmissions used in the past. But if GM and Tadge are truly dead serious about keeping a 'Vette up in the "best sports car in the world" discussion, then a DCT is mandatory in the future IMHO. Even if they put in an 8 speed auto that can hang with the current 8 speed Aisin and ZF boxes, there's just no comparison with the sheer shift speed of a dual clutch setup IMHO. Go drive an Audi S4/S5 with S-Tronic.

$0.02. I'm sure GM knows this, I'll shut up now.

Completely agree. With DCT we could see shifts in as little as 40 *mili* seconds. I know lot of people here are of the opinion "if it's not manual it's not a sports car", but no human can do that ha.

For anyone interested BMW did a good video/cgi showing how double-clutch works: (they show cutaways halfway through)

[ame]http://youtu.be/3168HrHGeLw[/ame]

Interesting video thanks.

This is a good discussion. I think the C7 certainly lends itself to a dual clutch application without hesitation, but meeting the production deadlines is always tough to pull together for a major vehicle launch. I bet it will show up soon.