Toyota Yaris Forums - Ultimate Yaris Enthusiast Site
 

 


 
Go Back   Toyota Yaris Forums - Ultimate Yaris Enthusiast Site > Second Generation Toyota Yaris Main Rooms > Fuel Economy Forum
  The Tire Rack

Reply
 
Thread Tools Display Modes
Old 08-25-2017, 11:28 PM   #1
07liftback
 
07liftback's Avatar
 
Drives: 07 Yaris Liftback
Join Date: Nov 2010
Location: Bay Area
Posts: 147
From 38mpg to 45mpg on 07 hatchback by hypermiling and detailing exterior

I just got back from a 450 mile trip going from San Francisco to Los Angeles. I wanted to implement all my different hypermiling techniques so I decided to wash, clay, and wax my car before my trip. Detailing it took about 5-6 hours since I'm guilty of washing my car maybe once every other year or less. That's gonna change now that I realize how much drag a dirty car produces.

The best mpg tank to date was a trip to Vegas using the exact same driving style and that only got me about 38mpg. For the longest time I couldn't figure out why my car was getting such poor mpg on the freeway, and it didn't matter that I did a full tune up including replacing the AFR/O2 sensor, spark plugs, filters, fluids, pcv valve, 45psi in tires, etc.

These hypermiling techniques included drafting behind large cargo trucks, never exceeding 65 mph (staying around 55mph), speeding up before a steep incline, engine off coasting (used very rarely).

After detailing my car, I decided to try a front upper grill block and used packaging tape on the seams between the hood and the front bumper. My license plate was already relocated to the lower grill and blocks a portion of it. I drove at night and arrived in the early morning and did so for each trip so my car wouldn't over heat, nor did I have to deal with traffic.

If I were to try another experiment on my next trip, I'd remove the passenger mirror as well as the wiper blades since I clayed and waxed all my windows.

So for those that haven't washed your cars in awhile and experience poor mpg on the freeway, try clay barring and waxing it. I'd like to find out if I'm the only one who experienced a large increase in fuel efficiency from doing so. Not only do you save gas money, you'd be saving your paint from failing prematurely, which will help your car retain it's value when resold.

Has anyone else experienced something similar after claying and waxing their cars?
07liftback is offline   Reply With Quote
Old 08-26-2017, 03:51 AM   #2
Pizzaboyracer
 
Pizzaboyracer's Avatar
 
Drives: 07 liftbsck
Join Date: Oct 2016
Location: Usa
Posts: 100
Good to know man thanks

Sent from my SM-J327P using Tapatalk
Pizzaboyracer is offline   Reply With Quote
Old 08-26-2017, 03:27 PM   #3
NYC-SE
 
NYC-SE's Avatar
 
Drives: 2014 Yaris SE
Join Date: Apr 2014
Location: NYC
Posts: 1,075
I find it unlikely that a 7mpg gain is possible from simply waxing the car. I'm sure a smooth surface will reduce drag but I suspect something else is responsible for your increased mpgs.
NYC-SE is offline   Reply With Quote
Old 08-27-2017, 05:22 AM   #4
dogsridewith
 
Drives: 2007 2-door hatchback
Join Date: Jul 2016
Location: USAnotCA
Posts: 750
Hypermiling

Quote:
Originally Posted by NYC-SE View Post
I find it unlikely that a 7mpg gain is possible from simply waxing the car. I'm sure a smooth surface will reduce drag but I suspect something else is responsible for your increased mpgs.
OP's opening post notes a number of aero mods done after the detailing and before the test run...then finishes with a contradictory question:" Has anyone else experienced something similar after claying and waxing their cars? "

So, needs to repeat test w/ a modified dirty car. And/or a detailed stock car.
dogsridewith is offline   Reply With Quote
Old 08-26-2017, 03:48 PM   #5
Pizzaboyracer
 
Pizzaboyracer's Avatar
 
Drives: 07 liftbsck
Join Date: Oct 2016
Location: Usa
Posts: 100
The clear coat on my car is peeling so I'm not sure if that affects it at all

Sent from my SM-J327P using Tapatalk
Pizzaboyracer is offline   Reply With Quote
Old 08-27-2017, 08:34 AM   #6
Rigaud
 
Drives: 2009 Yaris
Join Date: Jan 2014
Location: Rigaud, Quebec, Can.
Posts: 357
I did 45mpg (U.S. Gallons) with my 2009 Yaris just by driving it at 55mph for a non stop distance of 450 miles. Did nothing to it........just drove it steady.
__________________


2009 Toyota Yaris (Little toy)
2002 Audi A4 Avant Quattro 3.0L (Big boy toy)
1998 Subaru Legacy GT 2.5 (winter & DD)
Rigaud is offline   Reply With Quote
Old 08-27-2017, 07:12 PM   #7
Yaris709
 
Drives: 07 yaris
Join Date: Dec 2016
Location: Newfoundland
Posts: 99
I personally don't think that waxing yiur car will get better mpg. I dont wash my car often and i still get great fuel mileage. Highway driving 6L/100km at best with 120km/h average speed. Clean or dirty its the same. Don't mean to shit on you OP! I'd say your increase in mileage is due to the hypermiling
Yaris709 is offline   Reply With Quote
Old 08-28-2017, 09:06 AM   #8
tmontague
 
tmontague's Avatar
 
Drives: '08 2zr swapped Vios M/T
Join Date: Oct 2012
Location: Caledonia Ont.
Posts: 2,938
Iirc a few years ago there was a test done and it was found that a clean car will achieve better mpg. Lots of surface area paired with a smooth surface can do a lot. I don't think it alone is the reason for the op's very high increase in mileage but it has been shown to help and there is a definite plausible mechanism of action
__________________
No one ever wants to give a Yaris the point by...
tmontague is offline   Reply With Quote
Old 08-28-2017, 11:14 AM   #9
ern-diz
 
ern-diz's Avatar
 
Drives: 2007 Liftback
Join Date: Sep 2007
Location: CA all day
Posts: 3,794
Quote:
Originally Posted by tmontague View Post
Iirc a few years ago there was a test done and it was found that a clean car will achieve better mpg. Lots of surface area paired with a smooth surface can do a lot. I don't think it alone is the reason for the op's very high increase in mileage but it has been shown to help and there is a definite plausible mechanism of action
That's a trip, but it makes sense.
__________________
On Instagram

On Wheelwell
ern-diz is offline   Reply With Quote
Old 08-28-2017, 09:42 PM   #10
toad
 
toad's Avatar
 
Drives: street-legal go-kart
Join Date: Oct 2008
Location: bowser's castle
Posts: 627
i heard once that the reason truck(semi) wash places are so popular is for the same reason- not just to look good. i guess if it's your rig is clean and you drive all day for a living it would probably make a difference($) in the long-run!

i know they don't go as far as clay barring, however. i just finished clay barring BOTH my vehicles and you can certainly feel a difference when you drag your finger across the paint!
toad is offline   Reply With Quote
Old 08-29-2017, 12:23 PM   #11
ern-diz
 
ern-diz's Avatar
 
Drives: 2007 Liftback
Join Date: Sep 2007
Location: CA all day
Posts: 3,794
Quote:
Originally Posted by toad View Post
...i just finished clay barring BOTH my vehicles and you can certainly feel a difference when you drag your finger across the paint!
Big time. Just had it done to my better half's Honda and the difference was incredible. Her paint looked good, but felt like sandpaper. After the clay bar, it looked even more brilliant and felt like glass. It's really cool.
__________________
On Instagram

On Wheelwell
ern-diz is offline   Reply With Quote
Old 04-27-2018, 02:23 AM   #12
07liftback
 
07liftback's Avatar
 
Drives: 07 Yaris Liftback
Join Date: Nov 2010
Location: Bay Area
Posts: 147
Sorry to revive my old thread but I think part of the improvement could have been from drafting behind large trucks 70-80% of the time. On my way back from Los Angeles, I was only able to obtain 38mpg where I still drafted behind trucks 50% of the time and stayed under 60mph, usually 50-55mph. Not sure how everyone else in this forum is getting 40-60mpg easily on the freeway.
07liftback is offline   Reply With Quote
Old 08-03-2018, 05:11 PM   #13
Ilovemyyaris
 
Ilovemyyaris's Avatar
 
Drives: Blue 5 door hatchback Yaris
Join Date: Apr 2011
Location: USA but it has green light?
Posts: 25
Quote:
Originally Posted by 07liftback View Post
Sorry to revive my old thread but I think part of the improvement could have been from drafting behind large trucks 70-80% of the time. On my way back from Los Angeles, I was only able to obtain 38mpg where I still drafted behind trucks 50% of the time and stayed under 60mph, usually 50-55mph. Not sure how everyone else in this forum is getting 40-60mpg easily on the freeway.
Maybe... you're mostly going up hill?

I notice I get about 42 mpg going to my grandparents house, coming back I get about 47 mpg semi consistently. Back road going about 45 to 50 mph. Apparently grandparents house is at a higher elevation.

ALso, unless I'm within a car length distance with big trucks I don't notice much mpg increase. I have to be pretty close to them and cop pulled me over once and explained he wasn't too happy to see that. Legally you need to be within two car lengths he explained but didn't recommend doing that either.

Anyways I only got like 3 maybe 4 mpgs extra from that distance. I think I might get 1 or 2 mpgs at two ish car lengths behind big rigs. Which of course is better than nothing as it adds up. Going 70 on the highway gets me about 38 to 39 mpg within 100 miles. Same distance behind trucks got me 40 to 42 mpg. Of course it seems like the farther I go the better mpgs I get. went from georgia to michigan and got about 47 mpgs on the highway but it took a few hundred miles to max out mpgs. And of course on the way up and on the way back I got different mileage. but I believe 47 was the average for both trips.
Ilovemyyaris is offline   Reply With Quote
Old 08-04-2018, 10:29 AM   #14
dogsridewith
 
Drives: 2007 2-door hatchback
Join Date: Jul 2016
Location: USAnotCA
Posts: 750
hypermiling

what was the spacing to trucks on the 47 mpg run?
Quote:
Originally Posted by Ilovemyyaris View Post
Maybe... you're mostly going up hill?

I notice I get about 42 mpg going to my grandparents house, coming back I get about 47 mpg semi consistently. Back road going about 45 to 50 mph. Apparently grandparents house is at a higher elevation.

ALso, unless I'm within a car length distance with big trucks I don't notice much mpg increase. I have to be pretty close to them and cop pulled me over once and explained he wasn't too happy to see that. Legally you need to be within two car lengths he explained but didn't recommend doing that either.

Anyways I only got like 3 maybe 4 mpgs extra from that distance. I think I might get 1 or 2 mpgs at two ish car lengths behind big rigs. Which of course is better than nothing as it adds up. Going 70 on the highway gets me about 38 to 39 mpg within 100 miles. Same distance behind trucks got me 40 to 42 mpg. Of course it seems like the farther I go the better mpgs I get. went from georgia to michigan and got about 47 mpgs on the highway but it took a few hundred miles to max out mpgs. And of course on the way up and on the way back I got different mileage. but I believe 47 was the average for both trips.
dogsridewith is offline   Reply With Quote
Old 08-03-2018, 09:20 PM   #15
thebarber
daily driver
 
thebarber's Avatar
 
Drives: the #wrecho
Join Date: Jun 2006
Location: Grand Rapids, MI
Posts: 5,876
Buy skinnier tires.

I went from 175 to 195 and lost 5mpg (6L/100km to 6.8L/100km) doing 100% highway at 80mph
__________________
thebarber is offline   Reply With Quote
Old 12-16-2018, 04:38 PM   #16
07liftback
 
07liftback's Avatar
 
Drives: 07 Yaris Liftback
Join Date: Nov 2010
Location: Bay Area
Posts: 147
Quote:
Originally Posted by Ilovemyyaris View Post
Maybe... you're mostly going up hill?

I notice I get about 42 mpg going to my grandparents house, coming back I get about 47 mpg semi consistently. Back road going about 45 to 50 mph. Apparently grandparents house is at a higher elevation.

ALso, unless I'm within a car length distance with big trucks I don't notice much mpg increase. I have to be pretty close to them and cop pulled me over once and explained he wasn't too happy to see that. Legally you need to be within two car lengths he explained but didn't recommend doing that either.

Anyways I only got like 3 maybe 4 mpgs extra from that distance. I think I might get 1 or 2 mpgs at two ish car lengths behind big rigs. Which of course is better than nothing as it adds up. Going 70 on the highway gets me about 38 to 39 mpg within 100 miles. Same distance behind trucks got me 40 to 42 mpg. Of course it seems like the farther I go the better mpgs I get. went from georgia to michigan and got about 47 mpgs on the highway but it took a few hundred miles to max out mpgs. And of course on the way up and on the way back I got different mileage. but I believe 47 was the average for both trips.
I think there's some correlation between mpg and geography. Many have stated that gasoline sold in CA nets worse mpg compared with the rest of the country. I'm usually behind trucks at least 3 car lengths to avoid any sudden braking for whatever reason. I've had people cut me off last second and slam their brakes to try and scam me for insurance money.

Also, some of the trip on the way back from Southern California did have uphill climbs but it only lasts 10 miles or so.
Quote:
Originally Posted by thebarber View Post
Buy skinnier tires.

I went from 175 to 195 and lost 5mpg (6L/100km to 6.8L/100km) doing 100% highway at 80mph
I would try skinniner tires but I recently got into a near collision. I was inches away from rear ending someone who cut me off on the freeway and slammed their brakes to a halting stop. If I had skinniner tires (less tread contact), I definitely would've slammed right into him.
07liftback is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 01:39 AM.




YarisWorld
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.