fredtheturd

This is my first posting, so I thought I'd make this well worth my while and test the waters here at YotaTech.

I own a 90 4x4 3VZE 123k miles and have had it for over 3 years now. I've lifted it 4" suspension, 2" body and had 35's on it for a little while. After I realized those big meats ate gas like a fat kid eats hoe-hoes, I put the factory size tires back on. I haven't done any other mods to speak of, but my gas mileage still seems a little crappy. On the highway, I run around 3300-3500 rpm's while going 75mph and the poor thing doesn't seem to want to pull me up hills very well. It'll slow down a little and the cruise may even reset itself completely. Also, it seems that the colder the weather is, the worse the mileage gets. In the winter I was averaging 13mpg, and just recently when the temps were in the 90's I got close to 17mpg. This may seem pretty good but I remember getting over 20mpg even after I lifted the truck June02. I took it to the dealer about 2 months ago & they said everything was hunky-dorey.

Any suggestions or help in this matter would greatly be appreciated. I love this website! Reply on here or email me at fredtheturd@yahoo.com
Fred

kylerensmeyer

[hijack... sorry]

you mentioned fuel economy... and it got me wondering, i dont even know how many gallons my car holds... its a 95 with the 3.0L and i only get about 210 miles to a full tank in the city... im guessing its about 18-20, does anyone know for sure?

fredtheturd

I have about a 15-16 gallon tank and in the city I get batter gas mileage than I do on the highway with cruise control. I'm not sure if this is because I'm running lower rpm's or what.

AgRunner06

I get about 220 a tank which translates to about 15mpg.

fredtheturd, it seems like you are running too many rpms at that speed. Has it ever been regeared? Also, try doing the usual tune-up stuff and your mileage will improve. Don't forget that 02 sensor.

green91runner

be happy getting the mileage your getting... i am running stock height, 31's and 4.10 gearing and i only get 11mpg in the winter and 14mpg currently... slow on hills, all stock 3.0's are... there are a ton of threads about this do a lil search.

mt_goat

Fred, that sounds about normal to me. You have an auto tranny right? The lift makes for more wind resistance at highway speed, the aerodynamics of a brick wall.

AgRunner06

You guys are going to hate me but I get 20-21 mpg on the highway with 4.56s instead of 4.88s.

mt_goat

So what's the trick? Are you running lean?

fredtheturd

I don't believe it's ever been regeared. I don't see why it would have been. The truck was completely stock when I got it. No lift, no big tires, so I couldn't comprehend why anyone would regear it. I called Tim @ DOA a while back & he mentioned something with the TPS. Does anyone think this could be the culprit? Does anyone know anything about this animal? I checked the resistance at the different throttle settings & all checked out except for the closed throttle position. There was just a touch (100 ohms) too much resistance than specifications say. Any ideas?

mt_goat

Have you seen Roger's info? http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml

AgRunner06

Not that I know of. I've done all the tune-up stuff (plugs, wires, fuel filter, O2 sensor, rotor, cap) along with some power mods. I've got a high-flow cat and dynomax muffler. I've also cut out my airbox. My mileage will probably be a little better once I put my ISR back on. I also swapped in a set of rebuilt injectors last November. I've played with my timing but I think it's sitting back at 10 degrees BTDC but I do need to bump it back up a hair. The occasional bottle of Redline helps out too.

The O2 sensor is a big one along with the power mod.

That's it.

fredtheturd

so what rpm's do most of you run at going say...70-75 mph? And what has been the most beneficial mod in relation to mileage & power?

AgRunner06

At 70 by my speedo (it's off because of the bigger tires), I sit at 2800 rpms. I think 75 is about 3k on the dot. I don't drive that fast much because its going over 80 for me.

Everything adds up a little bit. So doing one or two things to help your mileage will work a little but not as much as doing all of them.

Tofer

i am running 31x10.5 on a 94 5sp. i get about 15mpg and get usually about 250miles per tank (athough i got 280 on the last one) i have a 4.56 rear end. sitting at 75 on the odo (71 on the GPS) i am turning about 3300 RPM, bump it up to 80 on the odo (76 on GPS) and i am turning just a hair under 3400. so everything you said sounds normal to me.

SWORDFISH92

Best highway i have ever gotten in my life with all the stuff i have on it: 300 to the tank. Ohhhh it was sweet!

Silver_Truck

I get 20 on the highway and about 17 mixed with 4.10s and 34s I got 20 mixed and 22 on the highway with stock tires. I've got a K&N intake headers w/full exhaust, new O2, OS valves, rebuilt and balanced injectors and a few other things. I got about 13 when I was running on only 5 cylinders.

Bigblock

I got the best MPG with 4.56's!I've tried 4.10's and 4.87's, but they were worse on fuel.I guess the 3.0's like the 4.56 gear.

sandcrawler

someone asked about the total fuel capacity; on my 93 i believe it is a 17 gallon tank...

fredtheturd

Well, I now live in Texas & I pulled 1400 pounds in a 5'x8' Uhaul trailer & got around 13mpg. I'm not complaining at all. I put a K&N OEM replacement air filter in & changed the brakes out. I was very pleased with how she ran! Thanks for all the posts. This place is great!