Hybrid Tahoe SUV

The hybrid SUV makes a lot of sense. I do wonder if they've taken some time from tuning the outside and applied it to their regen system. I also wonder if the 2nd motor is used on the 2nd axle.

 

<div class='quotetop'>QUOTE(hycamguy07 @ Sep 20 2007, 07:17 PM) [snapback]515515[/snapback]</div>

Uh, still dread them.

It would still use a LOT more fuel, and emit a lot more CO2. And still be a safety hazzard to us mere car owners...

 

<div class='quotetop'>QUOTE(ACORNBLUES @ Sep 20 2007, 08:37 PM) [snapback]515542[/snapback]</div>

Both of the motor/generators in the GM 2-mode hybrid system are in the transmission assembly.

Basically GM wanted to design a hybrid system that can be dropped into existing cars, so they decided to modify the transmission rather than design a whole new drivetrain.

http://www.autobloggreen.com/2007/05/01/ab...-and-gmc-yukon/

Makes me wonder if anyone will bother with the hybrid version considering the price premium for a modest 25% improvement in combined city/highway mpgs (i.e. going from 12mpg to 15mpg).

 

Minivan, GM, not SUV. Good engineering, poor marketing. My guess is that the typical person who decided to commute in a Tahoe doesn't much care about fuel consumption. Shrink the transmission and squeeze it into a minivan and there will be a market for it.

But consumption is still consumption. While 17 mpg is better than 12 (claimed 40% improvement), its still 17. (Does the Tahoe really get 12? Yep, fueleconomy.gov shows the E85 Tahoe is rated at 12, the straight gas at 16).

No mention of the price here, but prior articles on this suggested in the range of $5-$10K. At $5K, it definitely would be worth it based on lifetime vehicle costs.

So I can definitely see fleet buyers and other straight dollar-and-cents calculators going for it.

The arithmetic: Supposing that it gets the claimed 40% improvement in mileage, that the vehicle life is 150K miles, that gas is $3/gallon, and that there are no other impacts (e.g. on maintenance, on engine life), then putting one of these in an E85 Tahoe would save almost $11K in fuel cost over the life of the vehicle, in a straight-gas Tahoe, about $8K. All courtesy of the fact that if you consume a lot of gas, a decent MPG improvement therefore saves a lot of money, or, alternatively put, if you waste a lot of gas, wasting somewhat less yields significant savings. (Trying to forestall the inevitable comment that the hybrid transmission in the Tahoe saves more gas than the HSD in a Prius. Well, duh.)

I say, good for GM. Hope they make money doing it. If people are going to buy these things (I say with disdain, as I just found out that my brother test-drove a Hummer before buying his latest land yacht), then at least give them the option for minimizing the damage, conditional on that purchase decision.

 

<div class='quotetop'>QUOTE(hycamguy07 @ Sep 20 2007, 07:50 PM) [snapback]515509[/snapback]</div>

Who can't see that this is truly a GM work of art ... a 'must-have'. What's wrong w/ those crazy Europeans that they can't realize how much THEY all need 3 Ton vehicles too!
Especially since hybridizing is increasing the mpg from 13mpg to 15mpg


Must be a misprint ... shouldn't the ad say, "Illogical extream" ?

 

<div class='quotetop'>QUOTE(hill @ Sep 22 2007, 02:32 PM) [snapback]516235[/snapback]</div>

I thought it was going from 13mpg to 20mpg in the city? And 22 on the highway?

http://www.usatoday.com/money/autos/review...oe-hybrid_N.htm

Or did I just interrupt some FUDding? Sorry about that.

 

This article says GM quoted a 25% combined city/hwy improvement: http://www.soultek.com/clean_energy/hybrid...ahoe_Hybrid.htm

That's basically only a modest improvement, going from a combined 13mpg to 16mpg (or 12mpg to 15mpg if we are using the EPA's newly-downward-revised figures).

What I find interesting is that GM said it wanted to go with a 2-mode hybrid system for greater efficiency at higher speeds (hence the 4 fixed-gear-ratios during the high-speed mode), yet it seems that most of the benefit from the 2-mode system is in city driving (40% city mpg improvement vs. a much more modest 25% combined city/hwy mpg).

The buying public will decide by the end of next year if this is worth the extra cost or not.

 

<div class='quotetop'>QUOTE(Jonnycat26 @ Sep 22 2007, 04:07 PM) [snapback]516266[/snapback]</div>

Does this sound familiar? "WAAAHH, I can't get 60mpg in my Prius" ... so they "re-estimate" the Prius down to what, 45mpg. Generally hybrids increase mpg roughly 15-20% ... but this land boat? A 59% increase?? 22mpg just may be a stretch

<div class='quotetop'>QUOTE(JustLurkin @ Sep 22 2007, 05:46 PM) [snapback]516316[/snapback]</div>

As we race from $80 + per barrel to $100 a barrel, I'm certain they'll be a smash hit ... whether they get 12, 15 OR 18mpg.

 

<div class='quotetop'>QUOTE(efusco @ Sep 22 2007, 04:21 PM) [snapback]516270[/snapback]</div>

As of today, you can.

2008 EPA rated at 21 city/22 highway

http://www.autoblog.com/2007/09/26/gm-hybr...22-mpg-highway/


For comparison, if you adjusted the 2007 Highlander Hybrid for 2008 mileage ratings you'd end up with 27/25.

So the Tahoe is worse, but the Tahoe is signifigantly bigger. Suddenly the rumors that the two-mode Vue is supposed to hit the mid 30s don't seem so outrageous.

 

<div class='quotetop'>QUOTE(Jonnycat26 @ Sep 26 2007, 09:52 PM) [snapback]518258[/snapback]</div>

Good post. Not on www.fueleconomy.gov yet.

So that's 21 city for a 5300 lb Tahoe. Phenomenal improvement vs. the 14 mpg city for the straight-gas Tahoe per 2008 EPA data.

Just to put this in perspective, compare ton-miles per gallon, based on curb weight, vs the Prius.

Prius 3000 lbs, 48 mpg city = 0.0139 gallons/ton/mile.
Tahoe hybrid, 5300 lbs, 21 mpg city = 0.0180 gallons/ton/mile.

So this seems plausible to me. No Atkinson cycle engine, no CVT, not particularly aerodynamic, and the result is that the efficiency, for moving mass around the city, is about 77% as efficient as a Prius.

Fair enough. That's a heck of an improvement. If it were as efficient per ton-mile as a Prius, it would have to get 27 city. So there's room for improvement. But it's still way better than the straight-gas Tahoe.

 

<div class='quotetop'>QUOTE(efusco @ Sep 22 2007, 04:21 PM) [snapback]516270[/snapback]</div>

I can speak from experience on actual mileage as I just sold my 2007 tahoe and bought my son a 2007 Sentra. His combined mileage of which 70 % was highway and 30% city driving was 14.7 over the course of driving 13,000 miles. I took it on a 600 mile mostly highway trip and got 19.2 mpg.

It did have the 4-6-8 engine of course but it ran in 8 cyl. most of the time unless you were cruising downhill. The dealer verified that this was normal.

With a 20% improvement via a hybrid that would make an actual combined mpg of 17.6. Not exactly prius like but not too bad if you need a large vehicle with AWD.

 

<div class='quotetop'>QUOTE(chogan @ Sep 26 2007, 10:40 PM) [snapback]518279[/snapback]</div>

Actually it does have a CVT + 4 fixed gear ratios, which is the reason it has those clutches that cause John1701a so much angst. I think, when all is said an done, GM/BMW/MB figured that a fixed gear ratio is better on the highway than a CVT, and their numbers do seem to bear that out.

 

<div class='quotetop'>QUOTE(Jonnycat26 @ Sep 27 2007, 06:47 AM) [snapback]518393[/snapback]</div>

Running out of stuff to provoke me with, eh? Those that have been paying close attention see the lack of substance, just personal jabs.

SALES are what matter.

Attempts to divert attention won't make any difference once sales begin. They provide the measure of success.

 

<div class='quotetop'>QUOTE(john1701a @ Sep 27 2007, 08:04 AM) [snapback]518397[/snapback]</div>

John... you throw a hissy fit whenever anyone changes the topic, so if I could just remind you that we're talking about mileage, not sales. After all, you can't talk about sales for a vehicle which won't be on sale for a few more weeks.

 

<div class='quotetop'>QUOTE(Jonnycat26 @ Sep 27 2007, 07:14 AM) [snapback]518400[/snapback]</div>

Quite the opposite. The only appropriate time to discussion expectations of sales is before they begin; otherwise, it's like betting on a horse after the race has begun.


<div class='quotetop'>QUOTE(Jonnycat26 @ Sep 27 2007, 07:14 AM) [snapback]518400[/snapback]</div>

Interesting how you are attempting to seperate the two, subjects that are most definitely discussed together.

Purchase decision is a factor heavily related to MPG. Two-Mode has been promoted all along as a more efficient solution for highway driving than one-mode hybrids. Turns out, the EPA estimates don't actually reflect that for two-wheel drive. How do you think consumers will respond to finding that out?