I recently replaced the OEM RFT's with Pirelli RFT's and was trying to observe the gas consumption change. A drive from SF area to LA was ok, driving around LA was good getting around 42-45 driving easily with pulse and glide. When I got back, overall I thought consumption went down a couple mpg's as others have reported. I then took it in for a 25k service, asking for an oil change. Everything checked out great, however, after a few days I noticed average gas consumption dropped further below 40 and now hovers between 35 and 40. I notice that I can't keep it in EV as long as used to be able to. It's colder than usual now in the East Bay (east of SF) going from high 30's to low forties in the morning up to the high fifties in the afternoon. I remember that out in the east coast where I used to live, hybrid consumption dropped significantly in the winter. I don't recall this happening last winter here in the west coast and am wondering if they missed something during the service. I checked under the hood for anything loose and didn't notice anything. Any similar experiences or ideas on what could be causing this?

 

Were the temperature, roads and driving styles identical between RFTs and the new tires?

I find that only few degrees of temperature difference, especially if HVAV (heater) is on will make a huge difference in fuel economy in a hybrid.

 

It's interesting that you mention the heater, which is on part of the time with settings of 68-70F now that we are at the "bottom" of the Nor Cal winter. One observation I've made is with the battery charge state with the bar display. When it's above the halfway point, it is much easier to "pulse and glide", and I can drive easily around town in EV mode. I will set the HVAC controls at a lower temperature to see the difference.

 

For me, I found heater settings above 66 degrees had a large impact on my MPG. Especially when outside temps are in the 20s to low 30s.

 

to apples to apples comparison HVAC must be on OFF. Thsi way engine will not be forced to turn on to head the cabin.

I usually set the temp to 25 degrees C (77F) then set HVAC to off. This way the heated seats and steering wheel keep me toasty until I get on highway. In the city HVAC has a "huge", "Tremendous" impact on fuel economy.

 

Pardon my ignorance but how do you turn HVAC off? I can only see AC off/on, but nothing that refers to HVAC in general (to turn heat off).

 

That off button will turn the system off.
Heated seats, heated steering will still work if set to Auto. You'll also get some heat as the car moved and air flow comes in naturally and engine runs naturally, without deliberately turning the engine on for heating.

 

I never turn on the heat (unless wife's in the car), just turn on seat & steering wheel, and get 40mgp in winter.

 

I'm happy to report that my gas consumption went back to the way it was. I simply turned off the AC and lowered temps to 66!

 

Curious how the comfort, ride quality is with Pirelli running flats? Compared to Bridgestone.
see Michelin has RF’s as well. Thinking of replacing my Bridgestones with another set of run flats, but wondering about comparing brands etc. if anyone has done so . I see a lot going with Michelin CC 2’s but then buying spares, etc. Takes up too much room in trunk area.

 

Tire Rack recommended the Pirelli RFT, saying it was the quieter tire compared to the other options. I am pretty happy with them as they are a lot quieter and the car feels a lot more comfortable. It feels like new bushings were installed to replace worn ones! Full disclosure - the OEM's I replaced were at 4/32 to 5/32" depth.

 

Just read some Tire Rack reviews on these Pirelli's. Almost all non 5 star reviews said tread life is terrible. I'm hoping to find an alternative to the Bridgestone's. Going to stay with RTF's, don't have space to haul around a spare.

 

It has a better wear rating, it should last longer than the OEM's. If it lasts as long as the OEM, I'll be happy.