Fuel mileage feedback

To add to the oft asked question about fuel mileage for Sonata's, I just
completed a 1400 mile trip with almost all of it on interstates through the
mountains of Virginia and W. Va. as well as S.C., N.C, and Pa. I have a
2006 Sonata LX 4 cyl Automatic. I topped off when I left and returned and
kept records of intermediate fillup amounts. Using GPS, I took the actual
mileage covered and divided it by the actual gallons. I came up with 33.91
miles per gallon. Surprisingly, the on-board computer said 34.0 miles per
gallon, which is darn close. My 'traveling average speed' was 67.9 mph. My
tire pressures cold were set at 35psi, which is higher than recommended but
that's another story about 'recommended' tire pressures. Don't want to
start that up again. )
Anyway, that's what you can expect under the conditions above. I went from
Georgia up to Reading, Pa. It was cold up there and I even got to shovel
some snow....... I thought I left that crap behind me when I moved south..

Tom

 

To add to the oft asked question about fuel mileage for Sonata's, I just

Although there is no major detriment to tire pressure being set to the
max allowable by the manufacturers tire spec on the side wall, other
than risking blow-outs from overheating, it's usually ok to be a
couple PSI under that rating when the tires are cold. I don't get
shops that seriously under-inflate: it kills gas mileage. Anyway, it
all depends on the tires. If I have the Yokohama H4S on my '02 Sonata
at anything less than 31 PSI, I don't feel the performance and
responsiveness I am supposed to be getting out of 'em. Anyway, nice
story about your mileage.

- Thee Chicago Wolf

 

Yea, low pressure will kill mileage. At Christmas, in all the rush to get
going on the same trip as I just took, I forgot to check tire pressures.
They were all the way down at 24 psi. ( I got 31 mpg on that trip under
same conditions and speeds.
My present tires are rated for a max of 44 psi so 35 is reasonable and
promotes more even wear than the recommended 30 psi, which makes for a
slightly better ride but wears the outside edges off real quick - a common
problem with front wheel drive cars.

 

good mpg, but I didn't know you could get a 4cyl in the LX??

 

Impressive mileage. How does the GPS miles compare to the odometer?

Typically, my computer overstates about 1/2 MPG from what I calculate.

 

Actually, you have that backwards. Inflating to the max pressure
allowed by the tire maker LESSENS the chances of a blow-out due to
overheating. Overheating arises from UNDER inflation, not over inflation.

Matt

 

Tom, about what RPM are you turning at say 60 MPH? I've never gotten
above 32 MPG on the highway with my 4 cylinder with manual transmission.
I'm wondering if the overall drive ratio is a little lower in the
automatic. My trips have all been on I-80 in western PA which is fairly
hilly which probably costs me 1-2 MPG as well.


Matt

 

You're right!!! I was thinking of my Honda. My Hyundai is a
GLS. Sorry about that.

Tom

 

In the 700 mile trip, the Gps indicated 702 and the odometer was 697.
Pretty darn good......

 

Hi Matt,
You know I really didn't pay much attention to the RPM's because they vary
up and down grades since it doesn't have a lockup converter. I'll have to
pay attention next time I'm on the straight and level and repo

st it for you. The hills in Va and W. V. are pretty impressive too.

 

"since it doesn't have a lockup converter"

Why do you say that?? Almost (maybe) all modern Auto xmissions have TQ
lockup. It just unlocks on a strain (up hill or calling for power).

 

No kidding! I didn't think any modern car lacked a lock-up TC. That is
amazing. Are you sure of this?

Matt

 

Well, maybe partner is right. It's just that on even gentle grades you can
see the rpms increase from about 2500 to 2800. It's not a sudden step like
you would experience with a converter unlocking. It might be that they have
designed in a smooth 'downshift' of sorts. Anyway, I can't feel the 'step'.
I really could care less as long as it keeps working and giving me great
mileage for the type of car we have. )

Maybe hyundaitech can shed some light on it.

Tom