2014 IS300h vs 2019 IS300h Fuel Economy

ThomasD94 · April 14, 2019

Hey Guys,

Relatively new to the Lexus ownership game, bought a 2019 IS300h last month and a 2014 IS300h premier last week for mum, I have noticed so far the 2019 gets about 40mpg (1200 miles on odo) and the 2014 (37000 miles on odo) is getting 37mpg. Both in eco mode with aircon off and driving same streets (I reset both computers before driving this weekend).

I was wondering what fellow owners got and what I can expect?

Thanks, Thomas

ColinBarber · April 15, 2019

You will probably get mid 40s once you get use to driving a hybrid.

NemesisUK · April 15, 2019

Check the stats from http://www.fuelly.com/car/lexus/is300h to see what others get from the same models in real world driving.

ThomasD94 · April 15, 2019

5 hours ago, ColinBarber said:

You will probably get mid 40s once you get use to driving a hybrid.

Thank you 🙂

Jayw13702 · April 15, 2019

Most of my driving is around town and I average between 45-47 mpg in the winter, 48-50 in the summer and 50+ on a long run (fast A roads or motorway)

All with a/c on and econ mode

Sent from my Iphone using Tapatalk

JulesO · April 16, 2019

Only done about a 1000 miles in my 2019 IS300h - about 47mpg on the dash so far...

200h · April 16, 2019

at the moment i am returning 45.5mpg with 18" wheels

Hadrian · April 16, 2019

We tend not to use ours (2015) around town, and at the moment the display shows 47.5 mpg, it's usually a touch over 50 mpg.

LordByronUK · April 17, 2019

I consistently get 50-55mpg average between winter and summer, and even had almost 60mpg on good motorway runs. I've been told from the dealership this is exceptional, but I had a CT before and spent 3 years mastering how to get the most out of the hybrid propulsion system. It takes time, you need to change your style of driving quite a lot, but 50+ all year around is possible in the IS300h, and this quite a bit above the new WLTP figures (which are too conservative IMO). I was even getting 65-68mpg average on my CT towards the end of ownership. The IS in my opinion is an exceptional vehicle, and best Lexus hybrid in terms of performance, fun, economy, features and price, it's a great car and so underrated! I speak to people at work with Audi A4s, BMW 3s and they're lucky if they get even high 30s. Yes, those Audis and BMWs are slightly faster, but they rarely use that extra power, and personally I'd take much better fuel economy over 1sec more 0-60 any day of the week.

My tips for hybrid driving,

- Take your foot of the accelerator as early as possible and try to glide to a natural stop. If you need to use the break, just feather it as gently as possible. This will maximise regen.

- Use pulse and glide as much as possible. You can glide on the Battery alone up to about 45mph in the IS.

- Use gravity as much as possible to charge the Battery.

- Don't labour up to speed, actually better to change to sport mode, get up to speed quickly and then use cruise control. More fun that way too!

- Use cruise control as much as possible at speeds above 50. I find below 50 then cruise control seems to use the Battery less often than it could and holds the revs a little higher than needed.

- Try to stay in the EV power band as much as possible when driving around town (the thick blur bar after charge) and squeeze everything out of the Battery you can.

- Only use EV mode combined with ECO mode. This will avoid jumping out of EV mode. Also, only use EV mode when you have a full Battery and you know the roads you're using it in.

- And the more general rules for driving, don't accelerate up hill, save your accelerations for declines and try to stay at a constant speed (again use cruise control)

- Keep the car as light as possible, this also helps with gliding to a stop and maximise regen.

Follow these rules and I guarantee you will get close to 50mpg average, if not more. Hope that helps :)

Thackeray · April 18, 2019

On 4/17/2019 at 10:52 AM, LordByronUK said:

Keep the car as light as possible,

I always run the petrol tank down to about a quarter and then completely fill the tank. But I've wondered whether fuel consumption would be improved if the tank wasn't completely filled. A tank full of petrol must weigh as much as a moderate sized person. Have you ever looked at the impact of keeping the tank less full so that the car is carrying less weight?

ColinBarber · April 18, 2019

25 minutes ago, Thackeray said:

I always run the petrol tank down to about a quarter and then completely fill the tank. But I've wondered whether fuel consumption would be improved if the tank wasn't completely filled. A tank full of petrol must weigh as much as a moderate sized person. Have you ever looked at the impact of keeping the tank less full so that the car is carrying less weight?

Life's too short IMO. A tank of fuel is about 50 Kg in the IS - if you only fill up to half that's only a 25 Kg saving which probably isn't going to gain you 1% in mpg. If you have to make a slight detour to get to the petrol station then the extra trips will almost wipe out any financial savings.

MONTIMAR · April 18, 2019

Over 9120 miles my average cons is 54.7 mpg. I have been driving hybrids for the past 5 years so know how to get the best out of them. No winter driving as I move to warmer climes.

Mostly A/B roads with very little motorway runs. Very few short runs as we have a town car.

mpls · April 18, 2019

On 4/17/2019 at 10:52 AM, LordByronUK said:

I consistently get 50-55mpg average between winter and summer, and even had almost 60mpg on good motorway runs. I've been told from the dealership this is exceptional, but I had a CT before and spent 3 years mastering how to get the most out of the hybrid propulsion system. It takes time, you need to change your style of driving quite a lot, but 50+ all year around is possible in the IS300h, and this quite a bit above the new WLTP figures (which are too conservative IMO). I was even getting 65-68mpg average on my CT towards the end of ownership. The IS in my opinion is an exceptional vehicle, and best Lexus hybrid in terms of performance, fun, economy, features and price, it's a great car and so underrated! I speak to people at work with Audi A4s, BMW 3s and they're lucky if they get even high 30s. Yes, those Audis and BMWs are slightly faster, but they rarely use that extra power, and personally I'd take much better fuel economy over 1sec more 0-60 any day of the week.

My tips for hybrid driving,

- Take your foot of the accelerator as early as possible and try to glide to a natural stop. If you need to use the break, just feather it as gently as possible. This will maximise regen.

- Use pulse and glide as much as possible. You can glide on the battery alone up to about 45mph in the IS.

- Use gravity as much as possible to charge the battery.

- Don't labour up to speed, actually better to change to sport mode, get up to speed quickly and then use cruise control. More fun that way too!

- Use cruise control as much as possible at speeds above 50. I find below 50 then cruise control seems to use the battery less often than it could and holds the revs a little higher than needed.

- Try to stay in the EV power band as much as possible when driving around town (the thick blur bar after charge) and squeeze everything out of the battery you can.

- Only use EV mode combined with ECO mode. This will avoid jumping out of EV mode. Also, only use EV mode when you have a full battery and you know the roads you're using it in.

- And the more general rules for driving, don't accelerate up hill, save your accelerations for declines and try to stay at a constant speed (again use cruise control)

- Keep the car as light as possible, this also helps with gliding to a stop and maximise regen.

Follow these rules and I guarantee you will get close to 50mpg average, if not more. Hope that helps 🙂

Excellent post...

Simpsoid · April 19, 2019

Can confirm. I've tracked just over 31,000 miles in my IS300h on fuelly.com. Average is 46.5mpg. The summer months give about 10mpg more than the winter. I don't use Eco mode and usually have aircon running.

reeac · April 19, 2019

I get 45-46 mpg overall according to the fuel computer. This slightly surprises me as I know how to drive economically and my old Honda Jazz maintains a consistent 53-54 mpg although I can get it up to 70 mpg if I try hard ....mostly by avoiding braking. I therefore have the strange situation where my more economical car costs me a lot more in VED than the other one. A lot of my driving is on rural roads with poorish visibility and occasional big farm machines which occupy about 75 percent of the road width so not a lot of high speed stuff.