I knew you did, just helping out.

 

I knew you knew I knew. Thanks for helping out.

 

It will be strong. The transmissions are what's been holding GM back from being more competitive both in terms of power level and number of gears. There's too much riding on this launch to screw it up.

As much as I'd love to, I have not yet seen any blueprints of the new design. I don't know how many planetaries it will have in it. It's possible to build a 6-speed with only 3, but also possible to build one with as many as 5. A five-planetary gearbox would allow for single-event clutch-to-clutch shifting where every shift is only a clutch-pack engage like a 4L80/85-E. That would be awesome, but unlikely due to weight and cost. The most likely configuration will be a 3-planetary geartrain where some shift are a combination of an engage and a disengage of certain clutch pack or (hopefully not) band(s).

It could, in theory, go something like this:

First = forward clutch pack engage.
Second = clutch pack 1 engage
Third = clutch pack 2 engage, clutch pack 1 disengage
Fourth = clutch pack 3 engage, clutch pack 2 disengage
Fifth = clutch pack 3 holding, clutch pack 1 engage
Sixth clutch pack 3 and 1 holding, clutch pack 2 engage

Just a theory....

I'm not a fan of multiple-event shifts. To me those feel sloppy and unprecise. Of course single-event shifts would be cost-prohibitive.

I have heard the comment made in certain GM correspondance saying something like "It is cheaper and easier to build a 6-speed than a 5-speed." This leads me to believe that the 5-speed would have four planetary gearsets while the 6-speed has only 3.

 

Well knowing the road less traveled (quality over cost) and the road more traveled (fear over quality), I'm not holding my breath for the higher quality product scenario.

James - if they go for the 3-planetary gearbox, would this behave better than a 4L80 routed through a GV box?

 

i wonder how much it weighs?

 

That depends on how you define "behave"

The Gear Vendors OD is not computer controlled. It does not know or care what gear your trans is in, what your speed is, what your throttle position is or whatever. It simply works. It has a controller, but all the controller does is prevent operation at low speeds since the unit is powered by a pump turning at input shaft speed. It has a limited auto-drive mode which basically just engages and disengages the OD at certain speeds. It also has a few inputs that can be used to lock out operation - such as when in 4x4 mode or when in factory OD to prevent double-OD. The controller keeps track of how many times it's engaged. That's it. It is not automatic.

I define "behavior" as something that produces predictable results consistently at a high quality. The Gear Vendors OD does that. What it is not is integrated into the factory electronics to correspond with OEM shifting in any way. In that respect a fully self-contained OEM 6-speed would "behave" better than the 8-speed combination of 4L80-E and GV-OD. I like having 8-speeds on tap but I never use first over. My 4L80-E 2-3 WOT upshift takes place at about 65MPH which really means I have to be going 60 or less (based on a 5mph hysteresis) to get a downshift hit to second. Everyone knows how much more fun a 4-2 downshift is than a 4-3. The 4-2 is much more violent because you'll land right at the engine's peak HP. Witht he GV engage the WOT upshift moves to about 80mph which means I only need to be going less than 75mph for a good 4-2 hit. There are some instances on the freeway when it's important to let a bonehead driver know they've made a move which should be considered inappropriate. With a quick push of the foot switch for the GV I can ensure myself a strong 4-2 downshift over a much broader RPM range. I've got a stock converter in this thing, it has something like a 1800RPM stall speed. lol With the GV I can make up the ratio gap between the OEM gears with the splitter. It's fun.

 

I want one,I guess I'll have to find a wrecked Caddy next fall.

 

I don't know... I think I like my four-speed.

My buddies Jag X-type has a 5 or 6 speed tranny - not totally sure which, I just know it's got a crazy deep first gear and it shifts a lot. It also feels like it has a rather loose converter - 2500 to 3000rpm (no exaggeration there). It sure gets around nice and quick, but the tranny and drive by wire TB are always busy.

My sportbikes also have 6 speed close ratio trannies. I've grown to hate those bikes. I get so sick of shifting, that I skip gears when I commute on them. 1st to 2nd. 2nd past 3rd to 4th. 4th past 5th to 6th. It makes getting around much more enjoyable.

Another example, Lately, I've found it pretty enjoyable to disable TCC lockup in my stock converter and tranny. I just let it shift through it's 4 gears and that's it.

 

Cool, that sounds good to me. It is about time they made a better tranny than the 4L60E....

 

Wow thats a incredable amout of drag and wieght just for more gears James B. I just do not see the point other then being picky about gears like you stated above. Your excessiveness in drivetrain always gets me. Have you broke 14's yet?