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Hi there, I'm a new member and new to the site. Just thought I would post to say hi and ask a few questions.

1. I have a 1997 chevy blazer 4dr 4x4, I have tried very hard to get the best mileage I can out of this truck and am just wondering what is a realistic goal. My best ever mpg average for a single tank has been 19.32, is probably the best that I can hope for?

2. I will probably be getting new tires soon and want to factor fuel economy into my choice any suggestions on brand/models - I have been thinking about the kumho road venture apt kl51, which has a wear rating of 600, weighs 30 pounds and a max psi rating of 51 for $82 @ tirerack.com

Thanks for your help

Hi there, I'm a new member and new to the site. Just thought I would post to say hi and ask a few questions.

1. I have a 1997 chevy blazer 4dr 4x4, I have tried very hard to get the best mileage I can out of this truck and am just wondering what is a realistic goal. My best ever mpg average for a single tank has been 19.32, is probably the best that I can hope for?

2. I will probably be getting new tires soon and want to factor fuel economy into my choice any suggestions on brand/models - I have been thinking about the kumho road venture apt kl51, which has a wear rating of 600, weighs 30 pounds and a max psi rating of 51 for $82 @ tirerack.com

Thanks for your help

Hello nervousmini:

First of all, welcome to cleanmpg and I can assure you that 19.32mpg with some experience will be a low tank for you.

Aether glider has taken an explorer to 30miles per gallon, so that is realistically achievable, however you should start out slowly.

Be sure to click on the articles section and read "beating the epa-the why's and how to hypermile"

22-23mpg should be relatively easy to attain with some mild driving modification, so here goes.

-Air up your tires to max sidewall for maximum roll. If you hypermile the benefits of a harder tire increases exponentially. Your ability to roll for longer distances is pertinent to higher numbers. That alone should get you above 20 with your current driving state.

-Being that you have a brick shaped mobile, you might want to consider slowing down a bit on the highways. If I were you I'd go the slowest I can possibly go without being hazardous. Anything over 50mph though is a killer.

-time the lights to make sure that you're not racing from light to light. Focus on your average speed instead of your maximum. Shift as early as possible, if it's an auto, try to find the lowest speed your car shifts, and be light on the throttle to upshift at those speeds.

-Leave a buffer in front of you, that is, leave some room between you and the car ahead so that a traffic stop or slow down doesn't necessarily mean one for you.

-Try driving as if you don't have any brakes (dwb)

These are all the techniques I would recommend for now, the others are a bit more complicated and once you get the hang of this, you should be able to average around 25mpg without too much effort. There is also another explorer driver here, chilimac02 I believe who gets just about 25 on average.

With the warmer weather coming up, you should see very good numbers...Dont forget to air those tires up!

We'd want to know what transmission you have. Manuals have more upside with certain techniques. And you should share info on the type of trips you take (length, speed, hills, traffic, weather) and what techniques/driving style you employ. What is the EPA rating on the Blazer? You should get 125% of combined with an automatic. Maybe 150% in perfect conditions. With a stick, 175% to 200% are doable.

On the tires, I think you want the highway tires like it sounds like you are considering. Any mud busting tread will tend to increase rolling resistance and shorter life on pavement.

Study the Hows and Whys article, and focus on conserving momentum as previously mentioned (dwb). Try new techniques gradually, check results, and return for help. Or shelve a technique that doesn't fit your driving or doesn't help, and move on to another. I've run air pressure to 60 psi without reaching a point where it quit rolling better. PSI=MPG. Haven't been that high in the Tacoma with its big 35 psi rated tires, but inching that way.

Also, while you can shut the engine off at lights (FAS), you shouldn't FAS during any pulse & glide driving unless the automatic is flat-towable (4 tires on the ground like behind an RV). Most automatics are not flat-towable. My Fit pretty much is (some limits), but the others are not. I'd be shocked if yours is. You want the tranny and differential to get the lube they need... But again, don't rush into P&G. Start with dwl, dwb, and work up. Learn to glide in neutral through your dwb, and add P&G (engine on) later. The wrong pulse will hurt mpg.

I am disenchanted with automatics. I've worked a bit to get 42 mpg in the Fit (new epa 30 combined) and 25 in the Tacoma (old epa 17/20). But the big #'s are mostly folks with manual trannies. Main reasons: you cannot control the gear selection as well to use the engine efficiently, the tranny slips by design until it locks, and you can't shut off engine while gliding or if you can you have to restart with the key instead of the clutch.

Welcome

Like other asked- which motor-sounds like the 4.3 V-6?
Trans- probably a 4 speed auto trans?

19.3 isn't bad, but you can do better with practice.

My 1998 2wd Suburban gets an honest 21 mpg in pure highway trips with the CC set to 68 mph(but with road work and towns speed might average just 60 mph) In pure heavy city driving with minimal hypermiling( tire pressure, motor on in D P&G) I get 13-16.5 mpg with the Suburban. If it were newer I would shut down at redlights and get another 1-1.5 mpg city. If your starter is newish shut down at redlights.

Here is what you can do.
1)Low rolling resistance tires with at least 40 psi. Mudder tires or other heavily lugged tires kill mpg.
2)Is it raised- if so lower it to stock,
3)Syn oil 5w30 and syn lube in the diffs(75w90 maybe)
4)Don't put anything on the roof.
5)Pulse and glide in city driving.I do it with my motor on and the trans in D- the 4L60E trans seems to absolutely freewheel when gliding despite being in D. Between 25 and 40 mph I lose about 1 mpg per 2-3 seconds while gliding on a level road in decent shape(potholes slow you down).

6) On level highways most drivers will do better with the CC on. The best hypermilers can beat their CC , but it takes a lot of effort, so over a long trip it is tiring. Choose a low speed for the CC-say 60-64 if the speed limit is 70 mph-something safe, not too much slower than the rest of the traffic.Maybe 5 or so mph slower than the average guy in the right lane.

7)When possible, the left lane is smoother than the right, so it can get better mpg. However, you have to stay alert for traffic behind you. In general it is safer to just stay right! Might be illegal to be in the left lane when not passing-so keep that in mind, and you don't want to annoy fellow drivers.

Luck,
Charlie
PS- A crude guess is your 4x4 Blazer-about 4000-4200 lbs with a V-6- should get about 15% better than a V-8 2wd Suburban of the same era.Figure about 18 mpg pure city and 24mpg hy (an all out hypermiler could get much better than that, but modest hypermiling should get you at least one EPA size class better mpg with practically no(maybe 2-3 percent slower) loss in average trip speed). .It isn't very aerodynamic, so keep hy speed as low as reasonable. Oh, I've noticed that worn tires seem to get better mpg than new tires, so don't change your tires until they are truly worn out.

PPS In respect to shutting down at redlights- you probably use .4- .5 gallons per hour idling once warmed up. Folks commonly spend 12 minutes idling at redlights per day.This would be about 1/2 gallon per week,and maybe 1 gallon saved per fillup- in general in city driving you will get 1 mpg better -on average- just by shutting down at redlights. If your starter is good/young not a bad idea.

^ What he said.

First, thanks for all the replies and suggestions - it's nice to still see that there are a few good forums left that aren't full of junk ads and flame wars.

1. My tires are aired up to the max rating on the sidewall, 40 psi front and 44 psi rear - they are different brands front and rear. The tires are junk and will need to be replaced, but am trying to make it through the summer.

2. I do try to keep my speed down but living between milwaukee and chicago - my choice of routes are limited and have to take a mix of high speed tollway (limit is 65 but even semis are going 70-75), and very congested urban streets.

3. I have been trying some of the techniques listed - given my environment, I leave a buffer, time lights, dwb, and pulse and glide

4. The truck is an automatic, but with 156,000 - I am hesitant to try things like coasting with engine off and shutting down instead of idling, the starter looks like a real sob to replace.

5. I have replaced all fluids with royal purple full synthetic for engine, trans, transfer case, and diff.

btw - the comment on tires being better when worn, is true in my observations. When tires heat cycle they harden and the rubber stabilizes. The tires will also harden a bit as they age from oxidation. Hard rubber has less rolling resistance. Last but not least, less tread = less weight

Take care

Great! don't forget to log your miles so we can see your improvement!

Looks like you have it covered. I don't shut down the motor, or even put it in N while gliding. The GM trans just freewheels too well to do that, and my starter is also old/original.

Probably not possible to switch, but I would bet the minivan would get better mpg than the Blazer 4x4? You are right-keep the worn tires-cheaper probably lower RR.

Luck,
Charlie

Actually I do have a minivan (05 chrysler t&c), is does get slightly better mileage - but the wife doesn't try to maximize economy. I have the blazer out of neccesity (I have to be able to travel in ANY weather) not choice, so I am trying to make the best of the situation.

However, I do have a bit of good news on my quest to break 20mpg. In looking over the truck @ my last oil change I noticed quite a bit of free play in the steering and found a loose pittman arm and drag link. I have to order these parts but I threw the truck on the alignment machine at work (I'm am mechanic) just to see how far out the alignment was.... holy cow - I have almost a 1/2 degree of front toe in when I take the free play of the steering and push it in. I am dragging my front tires! I can't wait to replace those joints and do an alignment on it and see how my mileage improves. I was thinking of trying for as little toe in as possible - maybe 1/8 degree max, and try it for a tank or two. I also plan to force match balance my tires and trade least possible vibration for least possible pull as well.

Thanks again for all the help and support.

Log your milage, listen to the advice here, and you should find all your tanks find over 20mpg.

Another eureka breakthrough!

I was finally doing some of the repairs on my truck (oil change, replaced the front sway bar bushings and the steering links - still have to do that alignment though), but while I was letting the engine run to check for leaks from the oil change... I noticed that my a/c compressor was cycling on and off! After a little troubleshooting it turns out that my heater control panel is bad and was running the compressor all the time, irregardless of the setting on the panel. My a/c has been on all winter! So I just unplugged the compressor and stopped to refuel and reset my trip odometer for a fresh run.

I can't wait to see how my mileage improves with the a/c off!

BTW, how do I get my MPG log to appear in my posts?

well since my last post, my mileage went up almost 1.5 mpg!!! Still have to finish the suspension repairs and do the alignment, but what an improvement already. After finishing the repairs I am thinking of putting it on a diet - getting rid of the roof rack, removing the trailer hitch (i'll never use it) and anything else that might help.

Welcome Scott,
Sounds like your making improvements by leaps and bounds already.


Read this to add your vehicle to the mileage logs and then add your vehicles log to your signature: http://www.cleanmpg.com/forums/showthread.php?t=5095

Good luck and remember don't sacrifice safety for FE ever, ie worn tires are dangerous to you and others on the road. Just saying that an accident is more expensive if it could be prevented. - Dale

well since my last post, my mileage went up almost 1.5 mpg!!! Still have to finish the suspension repairs and do the alignment, but what an improvement already. After finishing the repairs I am thinking of putting it on a diet - getting rid of the roof rack, removing the trailer hitch (i'll never use it) and anything else that might help.

Strong work so far. I ditched my roof rack over 18 months ago and have not missed it. It seems to help not having that air brake over my head in a car that is already an aerodynamic nightmare.

Welcome Scott,
Sounds like your making improvements by leaps and bounds already.


Read this to add your vehicle to the mileage logs and then add your vehicles log to your signature: http://www.cleanmpg.com/forums/showthread.php?t=5095

Good luck and remember don't sacrifice safety for FE ever, ie worn tires are dangerous to you and others on the road. Just saying that an accident is more expensive if it could be prevented. - Dale

Thanks again to all for the encouragement.

I just wanted to say one thing real quick about the tires, so no one gets the wrong impression. I am a professional mechanic and would never sacrifice the safety of my family or others sharing the road with me. I have seen far to many "scary as heck" cars/trucks on the road to be anything but completely obsessive about my vehicles. If I can't make every car around me safe, I will at least make mine safe.

The tires are "junk" in my opinion, but strictly speaking are perfectly safe. They are just mismatched to the truck and each other and should be replaced just by age as they are about 6 years old.

Anyway, I'm not upset or offended by your comment Dale - I just don't want to give the wrong impression.

I tried the link for adding the logs to my signature but couldn't get it to work, I just got my first mac and I will assume that it's just me that can't figure it out - or maybe there is no easy mac way? I'll keep trying.

update -

Well during my last tank of fuel I have managed to get a few more things done to the blazer:

Removed roof rack - so much quieter and the truck just looks cleaner without it (worth doing even if it doesn't really help mpg) - saved 11 pounds

Removed complete tow hitch assembly - saved 32 pounds

Installed cold air intake - not sure if it will help but I had the stuff to make one so what the heck, why not try it....

I still have to get the time to replace the loose pittman arm and get the alignment done, but avg mpg for the last tank is now up to 21.383 mpg. I though at first my goal of getting 25mpg was a long shot but I think I might make it..

I would still like to add the log to my signature - if anyone out there is using a mac and knows how I would appreciate any hints on that as well.

Thanks as always for the help and support of the forum.

Anyway, I'm not upset or offended by your comment Dale - I just don't want to give the wrong impression.

No offense was intended either. You sound like you are really making great improvements and you may even surprise yourself with the high mpgs that you'll start getting from your efforts. Good luck. :D - Dale

... Installed cold air intake - not sure if it will help but I had the stuff to make one so what the heck, why not try it...

Can you disconnect this, or convert it to a warm air intake? The wisdom here is that cold air is for maximum full-throttle power, while warm air is for better part-throttle fuel economy.

Scott, have you viewed the this link (http://www.cleanmpg.com/forums/showthread.php?t=11357)?

If you still have issues, PM me and I'll walk you through it.

Can you disconnect this, or convert it to a warm air intake? The wisdom here is that cold air is for maximum full-throttle power, while warm air is for better part-throttle fuel economy.

I probably could put it back to stock, but the old airbox is a horrible design - I can't believe any air gets through it at all. I haven't fabricated the heatshield yet, so it's not quite a true 'coldair' setup. I hadn't really though much of the cold/warm air debate side of it, I was mostly trying to remove the restriction and help the motor breathe more efficiently. I'll give it a try for a tank or two and see if it makes a difference. But it would seem that the colder denser air would allow more power to be made at a lower throttle position and keep the engine rpm lower longer - I'm just guessing....

... I hadn't really though much of the cold/warm air debate side of it, I was mostly trying to remove the restriction and help the motor breathe more efficiently. I'll give it a try for a tank or two and see if it makes a difference. But it would seem that the colder denser air would allow more power to be made at a lower throttle position and keep the engine rpm lower longer - I'm just guessing....

Under part-throttle conditions, the breathing must be restricted in order to keep the engine from running away with excess power. That is what the throttle valve does. Helping the motor breathe doesn't do any good whatsoever until you have already set the throttle wide open, i.e. full power. Most of us don't drive in that condition very often, especially when pushing for fuel economy.

Part throttle efficiency is hampered by pumping loss, and warm air helps reduce that loss a bit.

Here is one thread on the subject. (http://www.cleanmpg.com/forums/showthread.php?t=21789). There should be several others floating around here.

Under part-throttle conditions, the breathing must be restricted in order to keep the engine from running away with excess power. That is what the throttle valve does. Helping the motor breathe doesn't do any good whatsoever until you have already set the throttle wide open, i.e. full power. Most of us don't drive in that condition very often, especially when pushing for fuel economy.

Part throttle efficiency is hampered by pumping loss, and warm air helps reduce that loss a bit.

Here is one thread on the subject. (http://www.cleanmpg.com/forums/showthread.php?t=21789). There should be several others floating around here.

Very interesting stuff - I see the point of partial throttle/restricted air intake and warm vs cold air for fuel efficiency/power output. The physics side of the argument make good sense, however for my own stubborn sense of satisfaction I think I will leave the intake as is (without the heatshield installed - I haven't made it yet anyway) and see what happens. I didn't throw away the original air filter housing so I can put it back if it doesn't work out.

Well, I figure it's time for an update - allot has happened to the blazer for the better and it's thanks to the members of this forum for the advice and encouragement they have given - THANK YOU!

Since I joined the blazer has gotten a pile of new parts and a host of repairs/improvements. Changed engine oil and filter (royal purple 5w30), replace idler arm, replaced front sway bar bushings, disconnected a/c compressor (bad controller would not shut off), increased tire pressure from 32psi to 44 front and 48 rear, removed roof rack, removed trailer hitch, installed (luke) warm air intake, changed front and rear differential fluid (royal purple 80w90), changed transfer case fluid (royal purple max atf) replaced pittman arm, replaced front sway bar links, replaced right front upper ball jooint, performed 4 wheel alignment (0 degree front toe and 0 degree front camber for minimum rolling resistance), lowered front end 1" (adjusted torsion bars), and last but not least installed 3M stoneguard upper grill block - SEE THE PICS IN GALLERY!

And the results - - - -

When I first got the truck I was averaging 15.5 mpg
My first tank after joining cleanmpg (tire psi up and me slow down) 19.33mpg

My latest tank 22.47mpg

Thats a 68% increase in my fe thanks to all of you! Anyway I have decided to make 27.77mpg per tank my goal which would give me 158.68% of epa combined - and a HALF A KILOTANK! Any suggestions (besides a sg and a clinic - I'm working on making at least the clinic happen) for what to do next?

Scott,

Impressive improvements! If you get the scangauge and the clinic you'll be hitting better than 25-28mpg for sure.

You could try the WAI for another mod. Best of luck. :D - Dale

Scott,

Impressive improvements! If you get the scangauge and the clinic you'll be hitting better than 25-28mpg for sure.

You could try the WAI for another mod. Best of luck. :D - Dale

Dangit, I knew I was leaving something off the list - just couldn't remember what. Installed (luke) warm intake on the same day I took off the roof rack and the trailer hitch. It's not really a full WAI but it does pull air from right next to the radiator without a heat shield.

Way to go nervous! Doesn't it feel good to improve so much?

Sgii is certainly the way to go. It will teach you so much about your vehicle. Moment by moment feedback is priceless.

Oh yeah, one of the best mods is the clock. Leaving early allows for lower speeds and the cpacity to manage traffic curveballs (back-up-, accidents, etc.).

Keep up the goo work, and keep posting your successes and setbacks.