Chevy's website for the 2007 Tahoe says it still has a 4-speed transmission. I thought it was getting a 6-speed :huh: ? So does this mean the estimated mileage ratings on it are actually with the 4-speed (28 hwy)?

No 6-speed automatic on the Tahoe yet. Only the 6.2 liter engine, which the Escalade will use, will initially have the 6-speed. It will supposedly eventually trickle down as production ramps up.

This seems to be a confusion with a lot of people, and even a lot of professional's are getting it wrong, mainly because of the way GM worded all the press releases--unless you REALLY search for mention of the 4-spd, you would think that the 6-spd will be in place across the board. I certainly thought that for almost the first day, until I read everything through a few times, knowing what to look for. Lutz did confirm, though, recently in his Podcast that even though only the 6.2L will be getting it from intro, once they get the production of the 6.2L fully up and running to planned capacity, it will take over for the 4-spd completely, and be in place across the line. Think of it as a situation like the Olds Intrigue or the CTS not getting their "proper" engine until the second model year--kind of a common thing for GM over the years.

Hopefully they dont make the 6spd all close ratio, usually kills highway mileage (why you sometimes see 6spd Manuals getting worse mileage than 4spd autos) Besides whats the benefit of a 6spd over a 4? 3% better gas mileage and maybe shave .2 seconds off the 0-60?

I guess it should keep the idiotic critics shut up. They've been complaining about the 4-speed Hydramatic for long already. I never had troubles with my 4-speed.

Exactly. I've never seen the need for a 50 spd transmission, but they are coming! Another silly marketing war is gearing up: number of gears. It used to be a decade or two between gears - now, only a couple years.

A stripped down for weight DOD 4.8L V8 version with a 323 to 1 axel ratio and a 6 speed auto would be COOL with the gas $$$$$$'s what they are today!

New 6 speed will have a .67 overdrive 6th gear vs. the .70 in the 4 speed and the .75 inthe 5 speed auto. So the 6 speed will lower cruising revs over the 5 speed by 8%. Or 160 rpms at 2000 rpms. The big difference willbe in the 1st gear and each succeeding gear. 1st gear will be in the 4.00 range vs. 3.06 in the 4 speed and around 3.57 in the 5 speed auto. The 6 speed will have over 30% more torque mutliplication in 1st than the 4 speed auto! So they will be able to put a taller rear gear in and still get the same acceleration and that will lower hwy rpms even further. Hopefully they will not lower hwy rpms so much that they start hunting for gears on slight grades.

Think of it as a situation like the Olds Intrigue or the CTS not getting their "proper" engine until the second model year--kind of a common thing for GM over the years.

[post="21231"]<{POST_SNAPBACK}>[/post]

Most automakers do this. Toyota upgrades the engine about half way through body redesign phases. Ford is doing this with the 500. The M5 wasn't released until the regular 5-series was out about a year.

Most automakers do this. Toyota upgrades the engine about half way through body redesign phases. Ford is doing this with the 500. The M5 wasn't released until the regular 5-series was out about a year.

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Well, kind of, but those really don't count--upgrading or changing the powetrain when a vehicle is mid-life is normal. Engineering a TOTALLY new vehicle, meant to have a new powertrain to go with it, but then not having the powertrain or certain components of it ready until ALWAYS the next, or 2nd, model year is what seems genuinely "GM".

Not saying it's a real black mark against GM, but that comparison is a litttle off.

Toyota is the only one that fits what you say. Ford, BMW, DCX, VW/Audi all do it. Nissan just keeps throwing the VQ in everything north of the Sentra.

Anyone notice that the shift lever in the pics of the 2007 Tahoe is the same shift lever that the 2006 HD's have with the 6 speed Allison. Maybe this is going to be the new lever for the 900's, but why then would they only change the lever in the 2006 HD's with the 6 speed and not all of the 800's.

New 6 speed will have a .67 overdrive 6th gear vs. the .70 in the 4 speed and the .75 inthe 5 speed auto.
So the 6 speed will lower cruising revs over the 5 speed by 8%.
Or 160 rpms at 2000 rpms.

The big difference willbe in the 1st gear and each succeeding gear.
1st gear will be in the 4.00 range vs. 3.06 in the 4 speed and around 3.57 in the 5 speed auto.
The 6 speed will have over 30% more torque mutliplication in 1st than the 4 speed auto!

So they will be able to put a taller rear gear in and still get the same acceleration and that will lower hwy rpms even further.

Hopefully they will not lower hwy rpms so much that they start hunting for gears on slight grades.

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(((WOW!!))) Thats good to know. With a 400 to 1 first I can see why they are not useing it in the smaller base Engine LITE DUTY models. The 306 to 1 in the 4 speed is ((FINE))!!----GOOOOO 4 SPEED!! http://www.cheersandgears.com/public/style_emoticons/<#EMO_DIR#>/AH-HA_wink.gif