Wanted to introduce myself. I've had a 2008 Yukon Hybrid since 5/24/08. I am very impressed with the vehicle but am a little disappointed by the mileage I am seeing. I've recorded distance and fuel put in for all of the fill-ups (except the fuel that was in it when I purchased and the first fill up). Over 1599 miles (four tanks), I've used 94.5 gallons for a 16.93 MPG average. The four tanks each were 17.3, 16.3, 17.9, and 16.3.

My driving style is "relaxed" but I do not watch the "economy meter". Could there be something wrong with my hybrid system? 16.9 MPG is almost 20% worse than the advertised economy.

 

First, Welcome to the CLUB!
We don't have many full-size, GM hybrids but I suspect what works on my Prius will also work for yours:

• hardest tolerable tires - check the maximum side-wall pressure and compare it to the door jam value. You can play safely within these limits and higher pressure tires have lower rolling resistance but sometimes have a harsher ride.
• low-speed warm-up - try to keep your speed as low as practical for the first 1-2 miles. This lets the engine and systems warm-up so the vehicle can go into hybrid mode. I typically cut through my neighborhood posted at 25 mph.
• low-speed cool-down - when approaching your destination, try to reduce speed to under the critical speed that allows running on electric mode. This will let you approach your final destination using the stored battery energy that otherwise might be lost in 'self-discharge' while it is parked.

These are the 'low hanging fruit' and should give you pretty good mileage.

GOOD LUCK!
Bob Wilson

 

use N!!! and tell me if its a killswitch for the engine.

 

Welcome, there are not very many of us here with the full sized GM 2-mode. I got my Tahoe in February and have been very pleased. I haven't pulled the tacky stickers off yet... I really don't use the Econ Gauge either, just instant mileage to monitor how I'm doing.

Bob is correct - I use most of my Prius techniques on my Tahoe and have kept my lifetime mileage at or near the 20mpg mark. It has been harder this summer with running the AC so much. Your 16.9 is surely better then you'd be getting in the non-hybrid Yukon.

It seems to me that most of the gain comes from getting the engine to drop down to 4 cylinders. Once you've come to speed, let up on the gas, then re-engage just hard enough to maintain your speed. After a while it becomes second nature.

Other hybrid driving knowledge applies. The hybrid will generally enhance economical behavior that works in any car. Longs trips are better than short trips. Anticipate stops by letting up on the gas and coasting rather than accelerating into a stop. (Sudden stops and starts are a huge mileage killer.) Sometimes choosing a different route helps.

Cheers,
Tom