I feel cheated
 

i bought a 01 grand cherokee, took it for a nice long test drive and promised me 22-24 mpg on the highway, as high as 26-27 at 55, and decent even in the city.

picked it up and I'm averaging aboy 30%less all from before, 12.5 according to the gauge. the brakes were sticking, fixing that picked it up a little, but still crap. They installed 4 new balljoints, i think maybe the alignment is way off, must have gotten an alignment with bad parts. I upped the tires to 38 psi, 5 above stock, that fixed it a little, but still not as good as the tet drive

even takes more gas pedal to make it go, something is deinately up. My scangauge 2 is on the way, i hope that will shine a light on the subject.

It's a GRAND CHEROKEE, come on! You seriously can't be shocked by this.

if this is what the computer told me i would have walked away, the readings are worse and takes more throttle to maintain speed

something is up

First, onboard computers are not good for getting an accurate MPG rating. Go by what you actually fill the tank with and how many miles you drove. The scangauge will also give a better reading than the onboard computer. Also, I don't know how long you've had it, but you should be comparing your MPG tank to tank, not day to day, because there are a lot of factors that can affect it.

Here's the EPA's website, click on 2001 Jeeps- Search by Manufacturer

Depending on your model, you're looking at 13-14 city, 19-20 highway. Maybe you were going downhill with the wind or something for the 26-27MPG that you saw.

If you bought a Jeep Grand Cherokee expecting good gas mileage, then you made a foolish purchase.

bandit86 -

Here is your EPA MPG :

2001 Jeep Grand Cherokee 2WD

http://ecomodder.com/forum/member-cf...ee-epa-mpg.jpg

CarloSW2

I've driven both the classic jeep straight 6 version, and the V8 4.7 chrysler.

They both get about the same mileage. Right about the 20 range on the highway and that's if you're being a very good boy. Most of the time my friends reported mileage in the single digits while in the city. The on board mpg gauge is full of crap, as well. It would over report by 3 or 4 at a time.

Could you explain this sentence:
"i bought a 01 grand cherokee, took it for a nice long test drive and promised me 22-24 mpg on the highway, as high as 26-27 at 55, and decent even in the city.

Who?
Who promised you?
you have over 50 posts. so you have read over 200 posted comments from various threads.

WTF are you complaining about!!!!!
Where is the surprise?

How, in anybody's right mind, can you possible make the statement that you were cheated?

If I sound a little rude, good, that's the message.
You buy a car that was designed and built 10yrs ago. DO you realize that in the world of effecient mpg that was the stone age?
And like Frank Lee said......"it's the GRAND Cherokee" THe Heavest most loaded one they make.

the display showed as 23- 24mpg instant on the highway on the test drive. thats what IT, the car itself promised. Now that I picked it up it's barely shows 20 instant on the highway. For whatever reason it was indicating much better MPG on the test drive then after I got it. THAT IS WHY I FEEL CHEATED, THE BEFORE AND AFTER TEST DRIVE NUMBERS DO NOT MATCH, no matter how I drive i cannot get more than 20. I have no idea what it actually is as I have not filled up for the forst time yet, but if you take a prius for a test drive and it shows 70mpg with your driving style and you buy it, then cannnot get more than 55 mpg after yiu take it home, would you not feel cheated? same thing.
I know a jeep is a pig, had the display said 20 on the test drive all would have been well. It's like a woman being the perfect little lady, you marry her and turns into a *****. Thats what this jeep did. promised better mog one day then it could deliver in the days since.

How many of you guys get more than the EPA estimate? could you with a jeep? I'm sure you could, and why could I before and not now.

Instantaneous MPG is different than average.

ok, you need serious counseling. IT didn't PROMISE SHXX. IT is an inanimate object.
The word 'promise' implies a covanet or agreement. IT can not do that.

Maybe you would seem more reasonable if you said "displayed"........

Maybe your test drive was downhill, or you had a good tailwind?

Or maybe this is the latest twist on car dealers rolling back odometers :-)

bandit86 -

Remember that the on-board gauge is typically biased in favor of the car. What jamesqf said is also very important. I have one section of the 210 West where I can get over 70 MPG on my SG, but I know it's because of a long slow decline.

The lesson learned is that if you had asked our opinion before buying the car, we would have been able to warn you. Here is a quick search of the Ecomodder Garage of "Make = Jeep", "Model = Grand Cherokee" :

EcoModder Fleet list - EcoModder.com

Of that list, I think this is the best of the bunch because it has great MPG + a lot of fuel log entries :

Kmachine : 20.38 MPG
Details: Jeep - 2003 Jeep Grand Cherokee Fuel Economy - EcoModder.com

CarloSW2

Angmaar -

Very good point. When I am in a steady-state cruise mode I can see fantastic MPG.

CarloSW2

^BTW, that is what the EM performance calculator does- gives the nice steady-state figures. Not knocking it, it's tremendously useful, but don't plug your #s into it and think you'll get the indicated fe over the course of the tank.

Instantaneous mpg when it is first reset doesn't mean you'd actually achieve said mpg at the end of the specified distance, sure at exactly 70 mph it may display 23-24 mpg if you reset the computer while drafting/ at steady state for a moment, before it calculates enough fuel and distance has gone through to get a more accurate reading, per the epa as referenced earlier the expected highway average is only 20mpg, therefore that would be a better estimate, (and the combined figure better still as that more accurately reflects 55% city and 45% highway cycle)

Frank -

Egg-zactly. If you let it get to you, a commute is an MPG yo-yo. The average is the reality.

CarloSW2

In all highway driving at 60mph, if all is well, that generation Grand Cherokee with a 4.0 I6 should get 20 - 24 mpg with no wind and no very steep hills. If it's not, and you can't get 13 - 14 city, something is definitely wrong.

I'd look into making sure wheel bearings are all good, tire pressures are about 2 psi higher up front than in back (if it's full time 4wd), make sure the front O2 sensor (or sensors, some have 1, some 2, depending on year and CA emissions) are good. Make sure the plugs are good and gapped correctly as well. Not a bad idea to change the fuel filter either, as some have reported a clogged one killing both power and mpg on those Jeeps.

From what I've seen with my mom's 99, the onboard mpg gauge (in avg eco mode) is usually within 1mpg of hand-calculated tank average.

As the driver of a 4500+ lb Dodge Dakota quad cab with a 4.7L V8 engine, I can only say this...

You seriously expected to get decent gas mileage out of a Jeep Grand Cherokee? Bwah-hah-hah-hah-hah!!!!!!!

i still dont quite think any of you understood the original post. the absolute best mpg i got on a test drive I cannot duplicate again, although today being warmer it was getting closer. I can't remember how warm it was when I took it for a test drive.

I never said anything about average numbers not matching, or tank filup not matching the display.

i did not buy the Jeep to get exceptional fuel economy, it's an all around work truck, I needed 4x4 which a civic vagon would not have had.

Subaru.

The ad at the top of the page says you can get into an '11 Gr. Cherokee starting at $31,000. Why, it can handle weather and all kinds of *gulp* adversity (like mall parking lots)!!! :eek:

I laugh at things like that. Winter is the only time I appreciate having a Jeep in parking lots: I can park on the snow piles that everyone else has to work around, letting me park closer.

just filled up, 23.59 mpg, 2/3 mostly highway, the 1/3 in a blizzard on the highway at lower speeds

last thing i did was spark plugs, battery terminals and the battery was low on acid

the spec calls for 0.035 or .89mm electrode gaps, the ones in the jeep were 1.5mm ( I checked), almost double what they should be

That sounds much better! I wouldn't expect to do much better than that, but it's still not terrible for a brick, and certainly much better than it was doing.

Chances are, the spark plugs were so worn that you were on the verge of misfiring, which would definitely cause a lack of power and lower mpgs.

Way better for sure, looks like I picked up 4 mpg Once it stops raining and snowing I want to change the gear oil front and back, must be thick the mpg is low for the first 5 miles even after engine is warm

Mine is a bit sluggish like that too for a couple miles in cold weather, even with fresh lubes. Part of it is thick wheel bearing grease, etc. It doesn't really do it in the summer though.

As far as gear oil, I'd go with 75W-90 front and rear. However, if you plan to take it offroad, tow with it, or any other use that stresses the axles, I'd bump the rear up to 75W-140 (as suggested in the manual).

, I just had to point out that there WAS a Civic Wagon with real time AWD.

Oops I messed up. I miscalculated the miles driven, i only got 19.7 mpg

Ah. In a blizzard though, that's still not bad. Last time I drove back up to college, it was heavy rain for the first 1/3 of the trip, light rain the next 1/3 and heavy snow the last 1/3. 16.5 mpg average :(

My jeep weirdness stuff...

The Jeep ecu does not adjust well to E10. (I've owned my Wrangler since 1994 bought it new.) Oregon used to switch to E10 in the winter and to regular in the summer. It was absolutely repeatable, I'd lose 4 MPG highway in the fall and get it back in the spring.

Then they started keeping the Portland Metro on E10 year round, I regularly drive to the eastern half of the state in the summer. 120 miles of virtually flat freeway I'd have a tank of the city gas and get 15 mpg going east, then fill up to come home and get 19 to 20 coming west to home (Depending on the crazy headwind we get in the Columbia gorge.) Its of note that the Eastbound direction I had a tailwind 90% of the time. (Standard prevailing wind in this area.)

Now its all E10 and my mileage stays in the 15 to 16 MPG range...

There are some adjustable crank position sensors that allow you to mechanically tweak the timing (The jeep does not use the distributor for ignition timing on most newer models.) It assumes a static timing point off the cps and adjusts the timing electronically. The ethanol cools the mixture and raises the octane unless the vendor used the ethanol to bring the octane up in the first place. The E10 rating is a minimum, its legal for them to be up to 15% without telling you in most states.

My jeep is also really sensitive to the Air filter, I run the stock air-box, and have been fiddling with switching back and forth between a K&N and a Standard Fram air filter. I've noticed power and mileage drop off pretty quick with the filter at what I would think is its half life. A quick shot of air backward through it from my shop vac cleans it right out.

I have a manual transmission but I've heard anecdotal stories that the Grands and the Wranglers with autos get better mileage with high performance fluid in them ...

I run redline or amsoil in the diffs and I use the stuff they recommend for Dana Axles, and ignore the MOPAR info because they spec too heavy of fluids in most gear boxes.
The AX5 manual behind the wrangler 4 cyl lasts way longer on lighter oil. (Its a known crap gearbox so YMMV) Funny thing is the book says use 70w90 synthetic but the viscosity of the special Mopar branded AX5 transmission fluid is the same as 20w50... At least through my viscosity gauge it is.... And when I got the trans rebuilt the builder said use 20w50 synthetic motor oil... Has worked for 120K now.. the same trans is used in some 80's and 90's Toyotas and they also spec a lighter lube from the factory...

Just some sortof tried and true data from my point of view...
Dave

comptiger5000 -

Yeah, you're being unfair to yourself if you're looking at blizzard-MPG. See how the summer goes and prepare for the next winter with block heaters and 99.9999% grill blocks, :p .

[EDIT: comptiger5000 corrected my bad-advice joke in next post]

CarloSW2

99% grill block on this would cook the tranny, so that's not an option. 50% is about the limit there. It'll definitely do better in the summer, but doing 60 on flat ground with no wind, it still gets about 19. I've seen 21 once, with the exact right hills, cruise at 59, and a slight tailwind. It was around 40*, so no A/C, but not cold enough to really kill the mpg. For mine, it really needs taller gearing, as a 360 doesn't need to turn 1750 rpm to do 60mph in this thing. Too bad the gear vendors OD units are so expensive, as that would drop my RPMs a lot (just under 1400 at 60, or about 1500 at 60 if I geared the axles a bit lower for better off-road crawling).

That is not accurate :mad:. 3-5% is the minimum in most cases and anything over 10% is illegal without the proper signage. They can't require usage of Ethanol if there is no supply for it anyway, they can only mandate that an oxygenate be used and Ethanol is the most popular with MTBE illegal. It is legal for them to sell Gasoline with ethanol in it in many states without signage, in that case any signage is voluntary.

Coil on plug is the new thing instead of distributors. Meaning spark advance is decided by the ECU. You can get a tune for that :thumbup:.

Even the distributor based Jeeps (91+ only for the 4.0) have the spark advance adjusted in the ECU, as the coil is computer controlled.