Is something wrong? 14 MPG HWY - Page 2

We travel to my in-laws about once a month, 136 miles one way with 112 miles of that being all expressway and the rest being country roads.
We did a experiment, we fill up and tried to drive 80 mph while on the expressway and 65 on the county roads. We averaged 72mph for the whole trip (round trip) and used 23 gals of gas.
Next month same trip but set the cruise at 65mph, averaged 64mph and used 13 gals of gas.
At the current price of $3.39 per gal we saved $33.90.
Driving 65 added 30 min round trip, that equals $67.80 per hour, so you are right, time is money.
I have driven a million miles (literaly) and most of them have been at 65, it is relaxing, safe and efficient.
Life is short, sit back and enjoy the ride.
And yes DI's do get better mpg than DII's, not even God knows why.

Some on here say that you need to change o2 sensors at certain intervals for better mpg. If the sensors were not doing the proper job, wouldn't you get a CE light?

As with any sensor, there is a tolerance level so the values can decrease and decrease while still remaining in the 'good' range.  Also with progressive learning from the ecu, if other sensors equal out the low O2 sensor issue, it could level out and not trip a SES light.

But yes with time, the O2 sensor loses efficiency and will decrease your engine's mpg.  Not sure how often is the 'optimal' replacement time to maintain the best efficiency though

From what I have been told is 65mph is the best speed
to get the best mpg,, this is for a Disco I, I think the Disco II
would be the same or within 5mph.
 
But the faster you go the less time you are using gas so
time per gallon is less (TPG) but MPG are less.
If you have to use ethanol that is BAD for MPG.

I wonder if you should like every 6,000 miles remove the o2 sensor's and wipe off with alchahol? or is that a bad idea?

I wouldn't touch the O2 sensors, but if you feel they need to be cleaned, sensor-safe cleaner, something like MAF cleaner is all I would ever think about using.

As for the milage, 60 mph is the optimal speed actually, above that drag outweighs the gains in speed, so your OPPORTUNITY COST of gaining one more mph in speed hurts way more at 60+

(been studying my econ today woo hoo!)

And x2 on the ethanol..that stuff burns like crazy..also you have to be careful, alot of states are putting E10 in the pumps for 87 and 89 and they don't have to label it on the pump!  You should be using premium anyway though

How many of you that have posted your mpg have a roof rack?

quote:

ORIGINAL: PITTDISCO

How many of you that have posted your mpg have a roof rack?

 
I do but it stays in the garage until I need it.

As far as weight goes, I wouldn't be THAT concerned about the roof rack..I think I saw somewhere that for every 300 lbs you add you lose 1 mpg or something like that.  Probably applys more to a smaller vehicle than something like the Disco that is sufficiently powered 

If it helps any, I had the roof rack on my Blazer for a while and saw a very minor impact in gas mileage, but when I added the grille guard to the Blazer, I lost about 1 mpg.  Probably more weight than drag causing it though.

OK, I am a very recent owner of a '99 Disco II.  I am coming off of a 1992 BMW525it.  (Needed something bigger for camping and mountainbiking.)  Anyhow, my wagon lost about 2-3 mpg with using a Yakima bike rack with the wind deflector.  Plus it was a ton louder inside the car with the rack.  (I went from an average of 22mpg highway to 25/26mph highway).  I recently (this month) purchased the Disco II.  I immediately changed the oil filter, air filter, fuel filter and added Mobile 1 Synthetic motor oil.  I run 91 Octane gas.  I am at about 180mi and at 1/2 tank.  My last tank was 310mi before the little warning light came on and I drove another 12 miles to get to a gas station.  When I filled it up it took 20.8 gallons.  The manual says that it has a 24 gallon fuel tank.  If I do my math correctly, that first tank was somewhere near 15.4mpg.  Not great gas mileage, but not atrocious.  (my Disco II currently has 102100miles on it.)  Oh yeah, I LOVE THIS TRUCK!!! I'll have pics of the DiscoII up soon enough...  Don't get me wrong, my wagon was a very good car and pretty cool to look at and drive, but this LandRover Disco II is something else altogether.  To Hell with the mileage, it's a fantastic rig.   


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The thing with roof racks isint the weight, it is the wind resistance.

Weird.  I hardly noticed a difference with the rack on the blazer..I guess it makes alot more sense though.  That is kinda the main wind line coming off the front end (the windshield/roof line). 

could you imagine one of these things in a wind tunnel?
Haha I would love to see that!

Roof racks make a big difference.
 
The better the mpg on the car/truck the bigger the drop in mpg.
 
I have a VW diesel that gets 48 to 50 mpg on the Hwy and with my roof rack I get 6 to 8 mpg less.
The rack is a Yakima with wind deflector for bikes and kayaks.

I did a roof rack mileage comparison with my Jeep Cherokee, when I owned it.  (similar aerodynamics (brick on wheels).  When I put on my Thule rack I lost about 1mpg, with ski racks on I lost about 1.5, with my "Pod" (closed plastic ski carrier) I lost btwn 3 and 4 mpg on average.  Bike ails on top of the bars no noticable diff in mileage, but put a bike up there forget it I'm down 4 mpg or more.
 
I noticed a 1-2 mpg diff due to drag when I put the ski racks on top of the disco.  So I only put the rack on when I'm heading to VT to play inthe snow!

I get 18.5 mpg on the highway but keeping the vehicle at 2400 rpm which is about 66 to 68 mph and I have Thule Cross bars on mine. They make noise so I know I am getting a little wind resistance with them. I do get about 17.6 mpg pulling my 2200# tent trailer. It is just a matter of slowing down. Speeds of 75 to 80 mph reduced my fuel milage to around 15 mpg not towing my trailer and down to less than 14 towing. Guys this is not a sports car, you have good vision out of the vehicle, enjoy the view as you are driving down the freeway. You would be surpised what you see going a little slower.

quote:

ORIGINAL: JayhawkinIdaho

I get 18.5 mpg on the highway but keeping the vehicle at 2400 rpm which is about 66 to 68 mph and I have Thule Cross bars on mine. They make noise so I know I am getting a little wind resistance with them. I do get about 17.6 mpg pulling my 2200# tent trailer. It is just a matter of slowing down. Speeds of 75 to 80 mph reduced my fuel milage to around 15 mpg not towing my trailer and down to less than 14 towing. Guys this is not a sports car, you have good vision out of the vehicle, enjoy the view as you are driving down the freeway. You would be surpised what you see going a little slower.

 
Is that with the 01 or 95?

The 18.5 is in my '01. Get about 14.2 mpg in town on the '95, it doesn't get on the highway much so I don't know what it does.

I think I'm getting about 11-12 around town in my D I. But I'm still working on the tune up stuff. I just spent $65 on bosch +4's last week, haven't had time to put them in yet...

We just took a 1600 mile trip in our 98 Disco I. We averaged just under 17 mpg.
It has new NKG plugs and 8mm wires. It needs O2 sensors.  I kept the cruise
set on 70 mph most of the time.
The mpg has been going down a little around town. I figured it was time for new
O2 sensors then on the trip it threw the O2 sensor code.
 
Mike