New Envoy, fuel milage

[bowtieboy]

Just picked up a new 2004 Envoy XL for my wife last night. It has the 4.2 inline 6 cylinder and 3.42 gears. What kind of realistic fuel mileage can we expect. Also anything I should be on the lookout for as far as problems or things that break? any advice would be helpful, thanks.

[afoon]

I bought a 2004 XL about 6 weeks ago. I have filled the tank 4 times since then and I have averaged 16.9 mpg. I am using a program on my PDA that calculates milage everytime I fill up. My driving has been well rounded during this time frame also, some around town driving and some expressway. FYI the driver information center has been reporting my milage to be around 16.3 to 17 mpg on each fill up so the info center is close to actual (some vehicles I have found to be off). Currently I have about 1400 miles on my Envoy. I am very happy with my Envoy and when people say "The millage isn't that good to todays standards", I simply tell them I didn't buy it for milage, I bought it for everything else!

[SoCalSLT]

I've had my '03 Envoy 4.2L for almost a year now. I watch the mileage closely and I get 18-19.5 per tank. 22 on the road. I have the driver info center that can give you instantaneous mileage and it has helped me learn how to get the most out a gallon.

[Lonnie44053]

Originally Posted by bowtieboy

Just picked up a new 2004 Envoy XL for my wife last night. It has the 4.2 inline 6 cylinder and 3.42 gears. What kind of realistic fuel mileage can we expect. Also anything I should be on the lookout for as far as problems or things that break? any advice would be helpful, thanks.

Mine is not getting good mileage.. The first tank it was 14.3 mpg, then it went up to 14.7 mpg, the third tank was 15.4 mpg, now its getting worse. 13.4 mpg on the fourth tank and 12.7 mpg on the fith.. I think the last tank might be the gas.. I bought it from rini rego's...

[otter7467]

I would try using a synthetic oil and maybe a better flowing air filter. i was at around 20 avg and now i am closer to 23. synthetic makes a bigger diff in higher hp (sports) car my Z got 24 mpg hwy until the first oil change an now if i am not killing it, it gets 31. if you do it yourself it's about the same cost as getting the dealership or a quick lube to do it.

[js02envoy]

well put it this way... it all depends on how you drive, yesterday on a trip from VA to NJ i managed 23 mpg but on the way there (NJ to VA).... racing next to a very nice chevy avalanche w/ the words ORANGE COUNTY CHOPPERS on the side of it and a driver that looked a whole lot like Paul Sr. i got just a hair over 19 mpg (trip one way= about 390 miles.) there have also been times when i have only managed 15 mph over around 230 miles, driving it hard on short trips.

on average i would say i get between 16 mpg and 20 mpg

it also depends alot on the weather... colder are is always a mpg killer

p.s. i have a K&N intake w/ a Borla Exhaust so that may be helping me on the highway and hurting me when i get on it.

http://www.cardomain.com/member_page...page_id=409773

[Bopper]

1 month old 2005 Envoy XL SLT, 6 cyl, 3.42 and stays in 4AWD.
It is getting a miserable 13.5 MPG around town.
I have yet to do any real highway driving.
I had a 2002 Mercury Mountaineer 6 cyl AWD that was getting 16.5 city and 23 Highway. Those #'s sound great now!

[js02envoy]

First off A4x4 is not all wheel drive! It is true 4x4 but it only turns the front wheels if the back slips. To be honest w/ you i wouldnt use it all that much unless you do alot of "off road" driving. Unlike AWD, A4x4 splits the power front to back equally and on dry pavement it's a bad idea, especially around turns. Personally the only time i use it is when the weather is bad (heavy rain, snow, etc), and for the occasional 75mph trips around turns... Otherwise i stick to 2WD and when it is truly bad out 4x4. I have never really noticed much of a decline in mpg in A4x4, or 4x4 compared to 2WD but i guess it really just depends on how you drive.

Try synthetic oil i've been using it for ever, and getting an average of 18-19mph, and as far as i'm concerned, thats not bad for an SUV.

and if i'm not mistaken the 2002 Mercury Mountaineer 6 cyl AWD only produces 210 hp and weighs 4566lbs. And when you compare that to the 275 hp, 4954lb Envoy XL or even the 4594lb Envoy you can see why the mph is different.

[jdmccright]

Yes, this is an old thread, but I did not see anything mechanical in the replies that may account for the low mileage.

The wife drives our Envoy XL (~97k miles) and is getting around 13-14 mpg. Granted, I'm not in the passenger seat when she drives so I can't comment on her driving style. I would probably label her as slightly aggressive. The truck is all stock, she drives with the A4x4 selected and A/C usually on. Can this alone be the reason for the low mileage?

I just replaced the spark plugs and the tranny fluid/filter...the front & rear diffs and transfer case are still due. No CEL or codes. Tires are inflated properly. During the fluid change, I noticed what sounds like an exhaust leak near the manifold in the engine bay, but haven't been able to find the source yet. Would this leak cause a problem?

Any other potential problems? Thanks!

[maxwedge]

After we are done with this we will close the thread, 3 years is too old, anyway I would scan it and look for a lazy o2 especially with an exhaust leak. My std w/b 2002 at 103k gets 17 mixed and 21 hwy, best driving conditions, winter 15. The mixed driving is no traffic lites for a 60 mile round trip to work.

[jdmccright]

I was able to move the exhaust manifold cover enough to see some black soot/discoloration on some of the manifold downpipes near where they come together, but none where they meet the engine block. So I went underneath and checked the bolts from the collector to cat...they weren't loose but not tight either. I tightened them up to 40 ft-lb (no specs in the manual...I guessed) and checked the manifold-to-block bolts (18 ft-lb), those were good.

I don't hear the leak noise anymore, but won't know if it is the cause of the low mileage until we burn through a tank.

Do the front wheels engage only when the rear wheels have detected slippage? I presume this is not an on/off process, power the front axle is transferred in increasing amounts (viscous coupling?). If so, can the front axle be engaged under high enough acceleration, such as from a stop? Knowing how this works could be of benefit to all leadfoots who blindly drive in A4x4 mode (read: the wife).

I've also been trying to find info on if/how to install the OEM "driver information center" on our SLE. Is it a separate console mounted to the roof? Or is it integrated with the instrument panel? I haven't found any pics to determine this.

[maxwedge]

Yes the ft diff/transfer case engages in awd when the wheel speed differential is detected , is your truck awd, or do you have a switch on the dash that selects 4h, 4l or awd? A4x4 will lower fuel mileage, and it will not engage during hard accel, only if it detected rear wheel spin.

[jdmccright]

It has the selector knob on the dash: 2wd, A4wd, 4HI, 4LO, and N. I know that SOMETHING is engaging when I switch between 2wd and A4wd because I can hear electric motors whirring when the engine is off.

I checked the option codes and didn't see anything about having a limited slip diff. According to the window sticker, it does have the 3.42 ratio. But one would think that a 4wd would have limited slip diffs...no matter in this thread. The 3.42 ratio should be yielding better economy than what I'm seeing...gotta be something else.

I found out that the DIC is not post-factory installable at all. It involves replacing the instrument cluster, the steering wheel (for the control buttons), and likely a crapload of other wires and sensors for the compass, outside temp, etc. Where did I find this? The owner's manual...duh. Think I'll spring $180 for a ScanGauge instead.

[jdmccright]

After fixing the exhaust manifold leak, mileage has improved to ~16-17 mpg in mixed driving. I'm not jumping for joy, but a 20% improvement is welcome.