GM Rationalizes Rear Drive

[Mr. Wyndham]

GM rationalizes rear drive: Sigma and Zeta architectures to be converged, Impala likely to stay FWD

General Motors' Cadillac-only Sigma platform (CTS, SRX, STS) proved too expensive for cars like the Pontiac G8 and Chevrolet Camaro. Now GM is merging the Sigma architecture with its other RWD platform, the G8/Camaro's Zeta, in time for the urgent 2011-model-year Cadillac STS/DTS convergence. Cadillac has locked in the new flagship's design. We hear designers are reworking the nose because the flashy headlamp design turned out to be too busy.

A rear-drive Chevrolet Impala is all but off the table. GM is unwilling to give up sales of the front-drive full-size sedan, which isn't ceding sales to the popular new Malibu. The Impala competes directly with Ford's Taurus, and the division already has a Zeta-based model, the Camaro, on the way.

Because the only other car on the Impala's aged W platform, the Buick LaCrosse, will soon be replaced with the Epsilon-based Invicta, the next Impala probably will ride on a stretched Epsilon II platform. Will an optional V-8 fit? Doesn't matter, as new Corporate Average Fuel Economy standards start to take effect in the 2011 model year, same as the next Impala's arrival.

The converged Sigma/Zeta platform will encompass six versions on three wheelbases:

Coupe: Next-gen Chevy Camaro, although Holden is still pushing hard for a Monaro version, and Pontiac may want a G8 coupe, too.

Coupe premium: Next-gen CTS. Same wheelbase, but gets forged-aluminum suspension for premium road feel, handling.

Midsize: 114.8-inch wheelbase, including Pontiac G8/Holden Commodore and possibly a Chevy sedan, but not the next Impala.

Midsize premium: Next-gen CTS. Also shares 114.8-inch wheelbase (a 1.4-inch stretch over the current car), but gets the upscale forged-aluminum suspension.

Large: 118.5-inch wheelbase for Holden Statesman/Buick Park Avenue (China), Holden Ute/Pontiac G8 ST, and maybe RWD Lucerne replacement.

Large premium: New STS/DTS replacement. Same 118.5-inch wheelbase as the large sedan, but with forged-aluminum suspension and longer overhangs.

But that's not the entire GM rear-drive story: The company is also working on a small rear-drive platform, primarily for Cadillac's forthcoming 3 Series-fighter, desperately needed to establish the brand in Europe. Speculation suggests this may be split into premium and regular versions, as well, with Holden/Pontiac/Chevy getting the regular models.

http://www.motortrend.com/features/a...es_rear_drive/

[The_Blur]

This is good news. The costs cut by this move should really hep GM take back that top spot by allowing GM to spend more on production.

[ToneyTone]

I'm not sure if this is a repost but here is the link

http://www.autoblog.com/2008/05/05/g...ge-with-sigma/

I have no problem with this.

[Mr. Wyndham]

Originally Posted by ToneyTone

I'm not sure if this is a repost

Not really, it's a different article! Threads merged. (ps...I think the link is broken)

I like the idea of consolidating these platforms. It's definitely cost-effective, an hey. What's good for Cadillac is good for me: Plus...this all but guarantees the 'survival' of Zeta cars.

[stovt001]

I read this on LLN. Some thoughts:

About time! I never saw the point of having both Sigma and Zeta.

This bodes well for the quality of Zeta. If it is good enough for the Standard of the World (Caddy) then we're going to have one smooth car.

I don't mind not seeing a RWD Impalla. As long as GM has a couple RWD coupes, sedans, and verts in both low cost and luxury levels, I'm fine. A RWD Impala would be redundant to the G8, and would ignore people who want a simple, large family sedan and don't worry much about performance. A FWD Impala would compete well against the Taurus, Avalon, and Accord.

If they make a lower cost (Pontiac, Chevy, Saturn, etc) version of the upcoming 3-series fighter, I would heavily consider it against the Camaro. Nissan, Toyota, Subaru, Mazda, and possibly Honda all have small RWD low-cost performance cars in development. GM should not miss out on this. The 2.0L TC is practically made for a car like that.

This is all a good sign that Chevrolet will be able to keep the Camaro affordable.

[DGthe3]

Isn't Zeta a modified Sigma anyway?

[LS9CamaroSS]

Originally Posted by stovt001

I read this on LLN. Some thoughts:

About time! I never saw the point of having both Sigma and Zeta.

This bodes well for the quality of Zeta. If it is good enough for the Standard of the World (Caddy) then we're going to have one smooth car.

I don't mind not seeing a RWD Impalla. As long as GM has a couple RWD coupes, sedans, and verts in both low cost and luxury levels, I'm fine. A RWD Impala would be redundant to the G8, and would ignore people who want a simple, large family sedan and don't worry much about performance. A FWD Impala would compete well against the Taurus, Avalon, and Accord.

If they make a lower cost (Pontiac, Chevy, Saturn, etc) version of the upcoming 3-series fighter, I would heavily consider it against the Camaro. Nissan, Toyota, Subaru, Mazda, and possibly Honda all have small RWD low-cost performance cars in development. GM should not miss out on this. The 2.0L TC is practically made for a car like that.

This is all a good sign that Chevrolet will be able to keep the Camaro affordable.

You know you make a good point there if Chevy had a small RWD car right now i'd probably be looking at it too. i hadn't thought of that before now... I prefer RWD over FWD any day for any weather (yes i know FWD is better in snow blah blah blah...) Depending on what it replaces/how much it costs i might have to look at that before the camaro depending on my budget...

[wild_weasel]

I basically ask this question as an invitation to be educated...so, could Chevy possibly drop a Cobalt down on a "small RWD platform" to compete with the aforementioned Nissan, Toyota, Subaru, Mazda, and Honda cars? It's up for a redesign soon right? A new Cobalt SS with RWD would kick some serious import arse...or maybe I'm wrong?

[SilverTurtle]

remember about 4 months ago when I was saying that a Camaro and CTS could share the same platform?

[SilverTurtle]

look, it wasn't even 4 months ago... lol

http://www.camaro5.com/forums/newrep...wreply&p=49743

Originally Posted by SilverTurtle

I honestly think that the Impala may go back to being RWD, anyway, even though the plan seems to be stalled... but, no matter what, I would presume that as long as the CTS, G8, Monaro and Commodore exist, the Camaro should be safe.

unfortunately, I seem to be wrong about the Impala, though... I guess we'll all have to be happy with the G8 GXP

[2001ragtop]

the sigma CTS front end uses upper and lower control arms. If they do merge Sigma with Zeta, it is possible all the cars will have this. But I'm sure they could engineer it to accept either one. It seems simpler to just have one suspension and that's it. You probably would be able to install all the cadillac aluminum control arms also if you wanted. Like others have already said, this is basically another extreme upgrade.

Yet again the game is changing.

http://search.live.com/images/result...stall%2F12.jpg

[ToneyTone]

Originally Posted by wild_weasel

I basically ask this question as an invitation to be educated...so, could Chevy possibly drop a Cobalt down on a "small RWD platform" to compete with the aforementioned Nissan, Toyota, Subaru, Mazda, and Honda cars? It's up for a redesign soon right? A new Cobalt SS with RWD would kick some serious import arse...or maybe I'm wrong?

Some folks would say that pontiac should get the small RWD coupe but since GM seems to be in love with creating a car for multiple makes. I say make the cobalt sedan FWD but make the cobalt coupe RWD along side the pontiac version.

[fastball]

I like that GM is sticking with RWD for those of us who want it. They are doing what they have to to keep it alive, and it appears the new merged architecture will survive CAFE.

It would have been cool to see the Impala go back to RWD, but I guess the folks who want large family sedans don't care which wheels drive it. So, in that reguard, I guess I don't mind. I have a few years of living to do before I take on a wife and kids

[Supermans]

I guess this is good news. Looks like the Camaro is going to have a long life ahead if GM advertises aggressively with the new Transformers 2 movie..