winter mileage VS summer mileage
 

for you 4 season types are you seeing the same mileage in the cold and snow? just curious

Re: winter mileage VS summer mileage
 

Definitely not, even with block heater and some grill blocking. I think due to:

1. Different gas formulation in winter
2. Using our snow tires
3. Mostly just necessity driving, ie: more short trips, local errands
4. Colder ambient temperature causing longer warm up times (except lately it seems to be Chinook season, maybe in honour of the pending Olympics?)

The above in no particular order. It's reassuring to reset the trip meter (which resets the mpg display on our HCHII) and see that full warmed highway driving still yields decent mileage. But the around town mileage is depressing ;(

Re: winter mileage VS summer mileage
 

It is funny, but after a month and a half of frigid temperatures here in Washington DC, We got a relief today. I was averaging in the summer and fall about 19.3 MPG. I just reseted the avg mpg on the computer, and at the beginning of the week I was getting 16.7 mpg. Suddenly today, with 54 degrees temp, my milage have been going up to 17.3 MPG on the same tank of gas! Hopely tomorrow I might get 18s. I noticed that the electric mode is working more now at higher temps. Changing subject, I had really bad luck with the original bridgetone tires. I had to repair then so many times, more than any other car that I had. I just lost one of then to a puncture with a HONDA KEY! I just bought an used tire so I can replace all of then together. Thinking to upgrade to 20s.

Re: winter mileage VS summer mileage
 

I have had my tahoe for a week now.
Not much driving, but based on the DIC. I am definitly getting lower mpgs due to lower temperatures and short frequent trip.
Of course I need more time to verify this info.

exactly my obsrvations thanks!
 

I think mine is due mostly to warmup as I don't have far enough to drive to the office to even get the thermostat to open. EV is almost non existant in the commute. glad i'm not going crazy here thansk for the confirmation!
:angel:

Re: winter mileage VS summer mileage
 

I just got back from a 77.3 km(48miles) roundtrip mostly highly with cruse control set to 50 mph most of the time.
I had reset all the DIC numbers before the trip. Weather was 22 C beautiful and sunny.
I averaged 10.3 liters/100km (22.8 mpg) :)
I noticed the following during my trip:
1. While crusing, I am on V4 most of the time.
2. While crusing,I didn't stay long on hybrid mode. Keeps on jumping from V4 to hybrid andsometimes V8 only when there Is a slight uphill on the highway.
3. If my tahoe is parked on an uphill forward, the fuel Gage showing more fuel In tank and vice versa.
4.after driving for 37 km, and arriving to destination. while I am in park, transmission temperature 60-66 c. The vehicle won't go into auto stop right away. I had to wait for a few mins for the ICE to shut down. Is that normal?
On the way back, each time I slow down on an intersection, it goes to autostop right away. Just wondering what would Cause the delay in going to autostop mode?

One last thing, how can i post pictures in this forum :) ?

Re: winter mileage VS summer mileage
 

No, it is a definite hit in the winter. And on lighter weight hybrid vehicles, gusty winds really damage their mileage. Because part of their improved mileage was based on low wind resistance. I used to do the grill block on our Toyota Prius but here in Texas, it could be 40F then 70F in two hours. It was just a hassle for a couple of miles per gallon.

The biggest key is warm up time as jet1 mentions and keeping it warm. I would be a little more leary about doing anything like a grill block. We have a BIG V-8 in there and it is necessary to keep the coolant temp constant on it for protection of the block. And that block is aluminum!

All of that said, I am really impressed that the cold weather hit is less than 2mpg. On the Prius, there is a thermos resevoir that the coolant is pumped into when the engine shuts down and then back into the radiator when you start...all to maintain engine temp and reduce warmup time. I don't think we have anything like that but, it really warms up quick. We had a week of temps in the low teens down here with highs in the 20's. My tank average then was around 18.5mpg.

I seem to affect my mileage more by the way I drive than by the temp. I love that the truck gets warm inside quickly and bet the a/c will cool the interior just as well in the summer. I may never be able to own a vehicle again, that depends on an internal combustion engine to provide heat or drive accessories...just a waste and horrible on comfort! Good post jet1.

Re: winter mileage VS summer mileage
 

High Guss. I have noticed that sometimes the ICE keeps running at a place that it would normally be in autostop. Remember that it runs for more reasons than just needed for horsepower, it also runs to charge the traction (300V) battery. That is probably why it was running, just a minimal topoff to the traction battery. I have also noticed that it doesn't have to run real long to do this. I will drive a mile or so in EV mode and then the ICE is going to run whether I increase demand for horsepower not.

Re: winter mileage VS summer mileage
 

Thanks Mel,
This is what I have been noticing also :)
Thanks for sharing

Fyi..
 

3. If my tahoe is parked on an uphill forward, the fuel Gage showing more fuel In tank and vice versa.


the float arm of the fuel guage runs front to rear so if your tank is low on fuel and you are parked on a slope, when you restart it may show you are out of fuel. when you get it level it will go back to a normal state but it takes a minute or 2. I initially thought I had a faulty sensor. seems to be more affected if you have 1/4 of a tank or less.