~mpg~ - Great Lakes 4x4. The largest offroad forum in the Midwest

Go Back   Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Chevy Tech
GL4x4 Live! GL4x4 Casino

greatlakes4x4.com is the premier Great Lakes 4x4 Forum on the internet. Registered Users do not see the above ads.
Search
Reply
 
Thread Tools Search this Thread
Old January 24th, 2010, 08:01 AM   #1
chevybtk
~~1995 chevy k2500~~
 
chevybtk's Avatar
 
Join Date: 01-10-09
Location: Mt Morris Michigan
Posts: 397
iTrader: (3)
Mentioned: 0 Post(s)
Talking ~mpg~

My 1992 k 1500 5.7 liter gets 10mpg highway and about 6 city..... is there anyway i can increase that or what kinda of pluga and stuff to run in it, or set up to increase that i have a cherrybomb w/no cat on there now w/duel 2-1/2 after muffler and dumps and rear axle, should i take that off and put a regular muffler on?..... I have standard AC wires, autolite copper plugs, 285-75-16 tires (but look goofy with smaller tires because i have a 3 inch body lift)....and also truck has very little power.......Could trans need replacing it has a bout 250K on it that dosent like OD on e-way but will stay in if i dont use cruise.........just need some advice guys......what should i run...
chevybtk is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old January 24th, 2010, 08:16 AM   #2
Yetti
Buy a Fiat! Save the UAW!
 
Yetti's Avatar
 
Join Date: 11-05-05
Location: 20 minutes south of Hell...
Posts: 14,387
iTrader: (10)
Mentioned: 2 Post(s)
Default

Hard to say whay you have so bad of mpg and week power, but I would be looking at doing some basic engine checks. Compression test the engine to see how worn your valves and rings are. also check your TBI. if you open the butter fly are the bottoms of the plates black and dirty looking? if so then you need to clean that crap. some times the ports in the TBi become very coked up and then it restricts the function. also the injector pod. I have seen old ones worn to where they drip badly while running. if you shoot a timing light at the fuel spray youll see the pattern. if you see alot of drips then you most likely have a worn out injector. replace as you see fit. just remember that gas as a liquid doesn't burn, it goes right out the pipe. the drips don't burn.
__________________
Yetti
Yetti is offline   Reply With Quote
Old January 24th, 2010, 08:27 AM   #3
chevybtk
~~1995 chevy k2500~~
 
chevybtk's Avatar
 
Join Date: 01-10-09
Location: Mt Morris Michigan
Posts: 397
iTrader: (3)
Mentioned: 0 Post(s)
Default

Yeah thanks injectors are new BTW...just did them about 5k ago......no drips and have a nice fan pattern...
chevybtk is offline   Reply With Quote
Old January 26th, 2010, 02:09 AM   #4
chevybtk
~~1995 chevy k2500~~
 
chevybtk's Avatar
 
Join Date: 01-10-09
Location: Mt Morris Michigan
Posts: 397
iTrader: (3)
Mentioned: 0 Post(s)
Default

Any other opinions???
chevybtk is offline   Reply With Quote
Old January 26th, 2010, 02:37 AM   #5
MilwaukeeF350
Dan
 
Join Date: 05-31-09
Location: Alpena/ Trenton
Posts: 883
iTrader: (7)
Mentioned: 0 Post(s)
Default

Ok can you add vacuum gauge? Then drive around city or highway what psi it at while drive.

Below 12 psi = terrible mpg. 13 or up= good mpg. 20 psi= BEST MPG.

It impossible to keep 20 psi myself.


Is brake drag? Isn't it in 4x4 mode ?


If that mpg was in winter that kind normal but little low.
MilwaukeeF350 is offline   Reply With Quote
Old January 26th, 2010, 02:47 AM   #6
CHVYPWR
D.I.L.L.I.G.A.F.
 
CHVYPWR's Avatar
 
Join Date: 11-05-05
Location: Vicksburg, Mi.
Posts: 1,646
iTrader: (12)
Mentioned: 0 Post(s)
Default

You're 3" body lift and larger than stock tires are going to kill your mileage all by themselves! I had a '98 ext cab Z71 that got 12.5 mpg no matter what!
I also had 285-75-16 tires and 2" lift. Installed new heads, complete everything tune-up, new O2 sensors, new cat converters, new cat back aftermartket exhaust and still was 12.5 mpg. Those big trucks are thirsty, you'll never have "good" MPG out of them.

You're biggest mileage improvement will come from driving habits. I changed my driving habits with my Blazer and went from a 15mpg average to a 17mpg average. My highest was damn near 20mpg city. Not bad for a brick!

Look here for some tips: http://www.gassavers.org/index.php
CHVYPWR is offline   Reply With Quote
Old January 26th, 2010, 06:50 AM   #7
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-28-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

My 88 suburban 5.7 liter with slight mods gets 10cty and 10hyw all the time. Not much you can do with these big old chevy's.
Disturban is offline   Reply With Quote
Old January 26th, 2010, 10:10 AM   #8
chevybtk
~~1995 chevy k2500~~
 
chevybtk's Avatar
 
Join Date: 01-10-09
Location: Mt Morris Michigan
Posts: 397
iTrader: (3)
Mentioned: 0 Post(s)
Default

thanks guys.....
chevybtk is offline   Reply With Quote
Old January 26th, 2010, 10:34 AM   #9
wave_crusher
I'll Direc your TV
 
wave_crusher's Avatar
 
Join Date: 01-20-09
Location: Big Rapids, MI
Posts: 5,272
iTrader: (22)
Mentioned: 1 Post(s)
Default

Quote:
Originally Posted by CHVYPWR View Post
You're 3" body lift and larger than stock tires are going to kill your mileage all by themselves! I had a '98 ext cab Z71 that got 12.5 mpg no matter what!
I also had 285-75-16 tires and 2" lift. Installed new heads, complete everything tune-up, new O2 sensors, new cat converters, new cat back aftermartket exhaust and still was 12.5 mpg. Those big trucks are thirsty, you'll never have "good" MPG out of them.

You're biggest mileage improvement will come from driving habits. I changed my driving habits with my Blazer and went from a 15mpg average to a 17mpg average. My highest was damn near 20mpg city. Not bad for a brick!

Look here for some tips: http://www.gassavers.org/index.php

Only the lift will make a difference, your pushing more air with a body lift, but the 285s aren't going to make much of a difference if any at all, I have 285s on my 96 and still get 15-16 city

Your best option is to consider rebuilding/replacing the motor and transmission, but transmission definitally if it's has 250k, then i'd consider upgrading your ignition system and air intake, you can pick up a set of headers to replace the stock manifolds, all that should increase your mpgs but at least 2 or 3, maybe more. Depending on what you use your truck for you could swap in a 4.3L v-6 or a 5.0L v-8. Couple that with the other mods and you could be looking at an mpg increase of at least 4 maybe 5 or 6 miles per gallon.

But like I said, rebuild/replace the motor and definitally do the transmission, if you do anything to the motor throw a set of vortec heads on
wave_crusher is offline   Reply With Quote
Old January 26th, 2010, 10:46 AM   #10
greygoose
I'm the dude
 
greygoose's Avatar
 
Join Date: 02-18-08
Location: New Baltimore / Presque Isle
Posts: 6,081
iTrader: (1)
Mentioned: 0 Post(s)
Default

383 TBI. Nice upgrade from GM performance parts.
greygoose is offline   Reply With Quote
Old January 26th, 2010, 10:53 AM   #11
IFS SUCKS
I like trees
 
IFS SUCKS's Avatar
 
Join Date: 09-20-07
Location: Lansing,MI
Posts: 5,796
iTrader: (6)
Mentioned: 0 Post(s)
Default

Throw the autolites away and get some GM rapid fires.
IFS SUCKS is offline   Reply With Quote
Old January 26th, 2010, 10:54 AM   #12
wave_crusher
I'll Direc your TV
 
wave_crusher's Avatar
 
Join Date: 01-20-09
Location: Big Rapids, MI
Posts: 5,272
iTrader: (22)
Mentioned: 1 Post(s)
Default

Quote:
Originally Posted by IFS SUCKS View Post
Throw the autolites away and get some GM rapid fires.
A spark plug is a spark plug, they're all pretty much the same, they wont make that big of a difference
wave_crusher is offline   Reply With Quote
Old January 26th, 2010, 10:57 AM   #13
IFS SUCKS
I like trees
 
IFS SUCKS's Avatar
 
Join Date: 09-20-07
Location: Lansing,MI
Posts: 5,796
iTrader: (6)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by wave_crusher View Post
A spark plug is a spark plug, they're all pretty much the same, they wont make that big of a difference
I disagree GM cars and trucks hate autolites.
IFS SUCKS is offline   Reply With Quote
Old January 26th, 2010, 05:20 PM   #14
chevybtk
~~1995 chevy k2500~~
 
chevybtk's Avatar
 
Join Date: 01-10-09
Location: Mt Morris Michigan
Posts: 397
iTrader: (3)
Mentioned: 0 Post(s)
Default

rapid fires are junk.....lol
chevybtk is offline   Reply With Quote
Old January 26th, 2010, 10:06 PM   #15
wave_crusher
I'll Direc your TV
 
wave_crusher's Avatar
 
Join Date: 01-20-09
Location: Big Rapids, MI
Posts: 5,272
iTrader: (22)
Mentioned: 1 Post(s)
Default

Quote:
Originally Posted by chevybtk View Post
rapid fires are junk.....lol
maybe except for autolites but generally any good spark plug works just as well as the next, but i am being hypocritical because i use the diamond fires in my truck lol I like the idea that they ignite fuel better
wave_crusher is offline   Reply With Quote
Old January 27th, 2010, 10:17 AM   #16
chevybtk
~~1995 chevy k2500~~
 
chevybtk's Avatar
 
Join Date: 01-10-09
Location: Mt Morris Michigan
Posts: 397
iTrader: (3)
Mentioned: 0 Post(s)
Default

lol yeah but what kind of muffler should i put on to savor a few MPG i got a leaky glass back right now.....and never changed my o2 sensor....?
chevybtk is offline   Reply With Quote
Old January 27th, 2010, 04:00 PM   #17
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-28-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by IFS SUCKS View Post
I disagree GM cars and trucks hate autolites.
They actually hate every spark plug but AC Delco's...I have tried every high performance plug on the market in both my Trans Am and Suburban and have always switched right back to the Delco's.
Disturban is offline   Reply With Quote
Old January 27th, 2010, 06:22 PM   #18
TeamDangerous
BUNDY HILL PIT TRASH
 
TeamDangerous's Avatar
 
Join Date: 10-15-09
Location: Jerome, MI
Posts: 83
iTrader: (1)
Mentioned: 0 Post(s)
Default

One thing you should check is the coolant temp sensor. I have come across quite a few of these that have a skewed signal, meaning the sensor still works, but the resistance value may not be what it's supposed to be. So if you have the ability, check the sensor. I have changed a lot of these that have been the cause of poor mpg or driveability problems like stumbles and rough idle.
TeamDangerous is offline   Reply With Quote
Old January 27th, 2010, 08:28 PM   #19
chevybtk
~~1995 chevy k2500~~
 
chevybtk's Avatar
 
Join Date: 01-10-09
Location: Mt Morris Michigan
Posts: 397
iTrader: (3)
Mentioned: 0 Post(s)
Default

yeah temp sensors brand new........muffler? and like a cold air intake?
chevybtk is offline   Reply With Quote
Old January 30th, 2010, 08:46 AM   #20
CHVYPWR
D.I.L.L.I.G.A.F.
 
CHVYPWR's Avatar
 
Join Date: 11-05-05
Location: Vicksburg, Mi.
Posts: 1,646
iTrader: (12)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by wave_crusher View Post
Only the lift will make a difference, your pushing more air with a body lift, but the 285s aren't going to make much of a difference if any at all, I have 285s on my 96 and still get 15-16 city
The 285's are much heavier over the stock 245's. That adds a lot more rotating weight to overcome. I've watched mileage drop on two of my trucks after going to a bigger and heavier tire. My GMC Canyon was the worst. I went from the stock 235's to a 30x9.5 LT and lost 2mpg!
CHVYPWR is offline   Reply With Quote
Reply
Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Chevy Tech

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 10:54 PM.


Powered by: vBulletin, Copyright 2000 - 2012, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
Page generated in 0.32741 seconds with 80 queries