D4-Better gas millage..

[2002_LS_V8]

hey guys, last night i drove the car around in d4 and it says i get around 16.5 mpg in town, now when i switched to D5 it went down to 15.1 in about 15 min... wouldnt it be better if the car drives at 1.5K rpm in town for gas instead of 2.5 like mine does most of the time in D4?? i guess its time to use D4 and keep D5 for the highway :shifty: by the way i was driving the same in D5 and D4 and my foot is kind of heavy.

 

[beaups]

d5 should nearly always yield better gas mileage. If you're not seeing that you are either misinpreting the data or you have a mechanical problem.

 

[JPsBored]

Got my trani rebuilt and guy told me that D5 was best for highway and city driving,, in D4 car is working harder,, and in D5 the overdrive kicks in but not enuff to waste any more gas than in D4.

Only time u may want to go into D4 is bummper to bummper traffic moving, for a long period of time.

Remember that ur gas miles will always be different,, depending on the weather,, the type of rode ur driving.

Your also counting on the fact that the gas miles comp is working perfectly,,lol and in this car,, thats pretty small chance.

 

[Boomhower]

I would have to agree with 2002_LS_V8. I've experienced better gas milage numerous times using 4th gear rather than 5th while easing around town with my car. I mainly use SST though. Wouldn't think that would matter much.

 

[Beamer]

Yea I think if you stay under 45/50 and use d4 your mileage may just go up. Only time I use it is in alot of stop and go, slow traffic or when I'm doing 70 or so and am going to need to slow for a turn than I flip it over to let the engine slow it down that way I can take it easier on the brakes.

 

[Jim Henderson]

These cars are very sensitive to driving conditions etc so a mileage change in just a few minutes would not be unusual. I can be getting 25+ mpg on the freeway for 30 or more miles and as soon as I get off it dumps quickly down into the teens. Don't interpret too much into a momentary mileage figure. Check it over several tank fulls and keep inmind weather/heat will also affect mileage.

Depending on the powercurve, you can sometimes get better mileage in lower gears since the engine may be running at an RPM where is makes better power and can loaf along. This engine seems a bit whimpy to me and I suspect the power curve is fairly high in the RPMs, so lugging around in 5th may not give you the best mileage around town.

Like I said try over several tankfulls.

Jim Henderson

 

[trinibassman]

Gas Mileage

I live in NY and my gas mileage sucks. Right now Im getting about 11.5 mpg. I had a bunch of missfires when I got the car, had to have the trani rebuilt (aamco sucks) and had to change my both cats. Now JP said something about the gas comp not working properly, what can cause that problem because I wouldn't doubt it. One day I drove 44 miles on the highway and used a quater tank.

 

[JattGary]

What are you guys getting for mpg those of you who got 20 inch wheels?
I just got my rims on last week and the gas mileage keeps droping. I use to get close to 16 with stock wheels now i'm at 14.9 on my V8.

 

[Patrick00LS]

on my 20's i'm getting around 18-19mpg

 

[chocolat1701]

I live in NY and my gas mileage sucks. Right now Im getting about 11.5 mpg. I had a bunch of missfires when I got the car, had to have the trani rebuilt (aamco sucks) and had to change my both cats. Now JP said something about the gas comp not working properly, what can cause that problem because I wouldn't doubt it. One day I drove 44 miles on the highway and used a quater tank.

hey i live in new york city too and i have avaraged 15.0 mpg only when i go to jersey and hit the highway for a few it goes uptp the 18 or 19 so you should not be in the 11. i have a 04 ls what year is yours.

 

[2001LS8Sport]

I prefer not to use overdrive around town. It causes too much "hunting" by the transmission. All that shifting in and out of o/d isn't good for the car. As a matter of fact, Ford used to state in their owner's manuals to not use o/d around town. I think they've gone away from that.

The reason you can see better mileage around town in direct instead of o/d is exactly what Jim said. Lugging the engine down out of it's preferred torque band will produce lower fuel economy. Keeping it in the "sweet spot" of the rpm range will improve economy. Nothing more simple than that.

By the way...the manufacturers know how important keeping an engine in the desired rpm range is to good fuel economy and emissions. That's why you are seeing transmissions with more and more gearing. Now, Nissan has added a variable transmission to their lineup (think snowmobile clutch). Many manufacturers have been trying to adapt this technology to their cars for years...and I think Subaru was the first to offer it. They are having trouble making it work reliably. But if they get it right...you are going to see a lot of it. It's pretty good stuff!

 

[trinibassman]

My LS is a 2000 though so I guess thats where the difference is. When Im on the high way and I reset the fuel economy I get up to 22 mpg and I usually come from Atlantic City to Brooklyn on a quarter tank.