GM Hybrids, Making a Difference Saving Fuel. Made for a Two Horse Trailer 40% improvement in fuel mileage in city, tows 6100 lbs 
I first drove the new GMT900 platform Tahoe SUV hybrid in 2007. Now GM adds to the list, I towed trailers with the GMC Sierra Hybrid and the Cadillac Escalade Hybrid comparing to a Yukon non hybrid. 40% fuel economy improvement in city miles-per-gallon gets your attention. Nice warranty, 100k and 8 yr for the hybrid, 5yr power train takes the risk out. Both hybrids and the Yukon towed the Cimarron 2H trailer well 
The full size GMC 1/2 ton is EPA rated 20city/20 hwy, yes 20 in the city. That's the story of hybrids, incredible mileage tooling around town. Part of that is to regenerative braking, which charges the batteries when you brake. With Active Fuel Management, the truck can run on half of it's cylinders. All amazing stuff when you look at it all together. Just write that check for $42,790. The majority of the extra cost of the hybrid can be covered by a Federal and State tax incentives.
Locking 3.08 rear axle with a Eaton locker and trailering package is standard equipment. These hybrids can tow up to 6,100 pounds. Add to these astounding numbers the fact that you can go nearly 500 miles on a tank. Only available as crew cabs, which is the most popular cab configuration anyway. Today's hybrid half-tons are limited in towing capacity by two factors: cooling requirements for the trucks' electronic systems, and torque limitations in some of the transmission’s gear-set changes.
The two-mode hybrid powertrain uses an electrically variable transmission that houses two 60kW electric motors. Two mode continuous electric ratio hybrid, 4 fixed gears and in between, has infinite gear options like a hydrostatic in a combine or hay swather. At low speeds (Mode 1), the first electric motor, replacing the torque converter, drives the truck off the batteries up to 32-mph, and as far as one to two-miles, depending on charge levels.
At high speeds (Mode 2), the second electric motor, at the back of the transmission, works with the fixed gears to create an electronically variable transmission (EVT). The Active Fuel Management (i.e. cylinder shutoff) V8 also uses this electric boost to spend more time running in V4 mode to optimize fuel economy. The large 6.0L gas engine helps keep the truck in V4 mode longer while providing a steadier torque curve across RPMs for the transmission to manage. When I tow, I like having a larger engine. The 6.0L has torque is the right choice for power in a hybrid.
Future GM Hybrids are reported to double towing capacity and make a hybrid truck an option for most trailers. Commercial class 6 trucks are taking advantage of hybrids' in city delivery trucks successfully, it's become a tested technology.
Several auto makers are working on the same hybrid platform with their own unique application. The hybrid pickups have a few unique exterior features to set them apart from standard pickups. Most noticeable are the polished 18-inch wheels, which save weight, and the standard tonneau cover for better aerodynamics—cloth on regular models, a three-piece hard shell if you get luxury trim. The front air dam extends 11 mm further toward to the road. And GM’s characteristic chrome hybrid logo green-leaf is mounted on each front fender and the tailgate.
These trucks fit a 1.8-kilowatt-hour battery pack beneath the rear seat, (left picture) and the Two-Mode Hybrid transmission replaces the standard truck automatic. To offset the added weight, the front lower control arms and differential shaft are made of aluminum. And GM engineered a special hydraulic bushing to attach the cab to the frame, damping new vibrations created by adding the 300-pound battery pack.
They were really quiet, sound like a golf car, because these hybrids can run on their electric motors at speeds of up to 30 mph. These hybrids use regenerative braking to capture energy from braking and coasting and store it in the battery for future use.
An efficiency meter in the dash will tell you how well your are driving for the best economy. The dash readouts tell you when you are running on 4 cylinders or 8 with Active Fuel Management. Picture right, no oil pressure in electric mode. It's weird to look at the gauges when in mode one, no engine so no oil pressure or RPM's on the tach.
GM Press Release
- The GMC Sierra Hybrid pickup truck, which combines the fuel efficiency of a midsize sedan with uncompromised full-size truck capability,
- $39,365 (including $975 DFC) for 2WD models with the 3HA package and $45,500 (including DFC) with the 3HB package
GMC Sierra Hybrid
The 2009 Sierra Hybrid joins the Chevrolet Silverado Hybrid as the only full-size hybrid pickup trucks on the market.
Equipped with GM’s two-mode hybrid system, Sierra Hybrid is offered in the crew cab body style and is also available with 4WD.
EPA-estimated fuel economy for 2WD models is 21 mpg city and 22 on the highway; 4WD models are estimated at 20 mpg in city and highway driving.
That mileage, combined with a 26-gallon (98 L) fuel tank, delivers a cruising range of more than 500 miles with 2WD models and more than 470 miles with 4WD models
Production begins in December of 2008, with delivery to dealers expected in early 2009.
Towing capacity is rated at 6,100 pounds (2,767 kg). A $2,200 federal tax credit is currently available to many customers who purchase the Sierra Hybrid.
A well-equipped pickup
Sierra Hybrid 3HA models include popular equipment such as the heavy-duty trailering package;
StabiliTrak electronic stability control; locking rear differential; EZ Lift tailgate and lock; 18-inch wheels; cloth seats;
XM Satellite Radio and OnStar. Also included are automatic climate control, steering wheel audio controls and Bluetooth phone capability.
Equipment that is specific to the hybrid model includes:
- 6.0-liter V-8 engine (332 hp / 247 kW)
- Low rolling resistance tires
- Hybrid ornamentation
- Soft tonneau cover
- Head curtain side-impact air bags
In addition, a Sierra Hybrid 3HB model is offered. It includes all of the 3HA content as well as leather bucket seats
with six-way driver and passenger power; Power Flow navigation with Bose audio and rear-seat controls; rear park assist;
power adjustable pedals and a three-piece hard tonneau cover. MSRP is $45,500 (including destination charge). 
300-volt for two-mode tranny and AC, 42-volt for power steering, 12-volt accessories.
Quick disconnect on the battery. I suppose if 300 volts has a problem, you'd want to shut something off.
It's odd looking at the front of the engine with no fan, no power steering pump or belts.
Upper Left gauge, picture right is the economy gauge that shows how you driving habits effect fuel mileage.
Cadillac Escape Hybrid for 50% Improved City MPG
As big as it gets in a hybrid SUV. Magnetic Ride Control, Automatic Rear Leveling Control. It's the fastest auto air suspension I've tested. 22" wheels so I have enough bling. Heated and cooled seats work for me. In the NAV system you can see where the power is coming from on the hybrid. Automatic windshield wipers and auto dim for the lights. I followed a truck that had dim tail lights and my lights didn't auto dim. Did have 115 volt outlet which I missed on the Sierra hybrid. No spare, just a sealant kit with air. 20 city 21 highway mpg all for $72,865
Standard traction control, remote start. coil spring rear suspension is not my favorite for towing but the rear air leveling stays put on this Caddy.
Picture right, fun watching mpg real time.
110 volt outlet in the Cadillac. I like power tools like laptop, battery charger, air compressor. Disappointed that the GMC Sierra didn't have an outlet.GMC Yukon with Flex-Fuel 
GM jumped in with both feet on the Ethanol bandwagon with the most flex-fuel models. It looks good when E-85 is a dollar cheaper than gas. But at least GM is trying with hybrids, Active Fuel Management (8 to 4 cylinders), Flex-Fuel, the Yukon with 5.3L and 6-speed auto with double overdrives is EPA rated 14 mpg city, 20 mpg highway.
6-speed auto is a big improvement with the 5.3L gas engine. Plenty of room, optional integrated trailer brake controller, a good SUV for towing 8400 lbs in a 4x2.
Yellow is the theme for E-85, I guess the color of corn as in corn alcohol. 
Both hybrids and the Yukon towed the Cimarron 2H trailer well. Cimarron has one of the easiest towing bumper trailers. I think it has to do with the shape of the V-nose from tongue to the outside wall. Being all aluminum I'm sure helps.
LinkBack URL
About LinkBacks
Asteroids Champion!
Mr Truck's review of the GM Hybrid 
Reply With Quote
Martial Arts, the great equalizer for the vertically challenged. 