Exhaust/air Filter Swap Vs. Mileage Increase

[jdw174]

OK guys. ?I'm not one for spending a lot of bucks on "dressy" items, but I will drop a dime on something if it will increase mileage. ?Wanting the best I can get out of my soon-to-be-delivered AV, I'm considering installing a K&N filter element and a Magnaflow MUFFLER ONLY.

That said, I'd like to hear from any of you who have done these two mods and would like to know if it made any difference in your gas mileage? ?I've been down the Flowmaster road and couldn't hear myself think inside the vehicle, so I don't care a whit about what a "mellow sound" it makes. ?(Mellow is fine, as long as it's kept OUTSIDE the cab )

The only thing I'm looking for here is...do they work? ?or not

(Looking for Magnaflow owners only here)

 

[Sunshine_Kid_01]

Not trying to be a wisecracker, but did you really get a Chevy Avalanche with a concern toward gas mileage? No seriously, lets say the filter did a .1 mpg increase or even a 1.0 mpg increase. Does it really matter? The way you drive the vehicle will affect the gas mileage more than any add-on you are considering. People that put these mileage increasers on their vehicles usually baby the vehicle to check the new mileage, and alas, it improves! Well, of course it did, because their driving method affected it!

 

[ultravorx]

Hey, whats ups. I have a 2002 2500 Avalanche. I was getting about 10 mpg on highway, and 7-8 city driving. All easy driving too. I then put in a volant cold air intake and 2 flowmaster 40 series mufflers. Even while "gassing" it abit more than usual, i did see an increase. I was getting about 13mpg on the highway and about 10 mpg in the city. Granted you didnt buy the av for gas miliage, this little combination increased performance and mpg.(i know some of you will scream at me for saying this) but its true. I really saw an increase.
Frank

 

[jdw174]

Not trying to be a wisecracker, but did you really get a Chevy Avalanche with a concern toward gas mileage? ?No seriously, lets say the filter did a .1 mpg increase or even a 1.0 mpg increase. ?Does it really matter?

The answer to your questions are 1. No, and 2. Yes.

In reference to #1, I bought the AV for the ride and the utility it affords, but NOT if it requires filling twice a week. Should that happen and it can't be rectified, it will be gone soonest. Been there, done that with a brand new '88 GMC 4WD. 10mpg around town AND highway, and 7mpg towing the bass boat. I don't want a repeat performance. Gas ain't 25 cents a gallon anymore.

As for #2, let's say I "baby" the rig (driving at the speed limit...no jackrabbit starts, etc), and I get 15 city and 18 hiway. Would I be willing to spend about $250 for an air cleaner and muffler if it would pick up another 2mpg? Sure I would. But not for an increase of a tenth or two. It's not worth it. That's why I posted this question...to find out if anyone had done just this and whether or not it had helped and to what extent.

 

[dmacker]

I have the very setup you are referring to. I have noticed a very slight increase in mileage but a big increase in pickup with very little increase in the in-cab noise level. By slight I meann from 17.5 to 18.5 on the highway. Around town mileage varies too much to tell.

My Av ihas less than 3000 miles so it may not all be due to the mods.

Good luck.

 

[Sunshine_Kid_01]

JDW174,
Let me clarify what I was trying to say. Gas mileage gimmicks don't work. Never did. GM and others have improved the polution output, but the mileage is truly (primarily) a function of weight of the vehicle and power of the engine. I know, there is effect from wind resistance, tire resistance, dirty plugs, dirty air filter, etc, etc. But on a brand new truck, with the billions spent by the manufacturers, gimmicks don't work. Proven time and time again. If they did work, they would have installed them! My 2-ton 1970 400 cu in. Pontiac Catalina got 15-17 mpg. 33 years later, my 2003 2 ton Av does the same, it just pollutes less.

If you want a $250 air filter cause it looks neat and sound throaty, then go ahead. But I would not do it for a guaranteed mpg increase.

Just my two cents.

 

[jdw174]

DMacker, that's just the kind of response I'm looking for. Thanks a bunch. You increased your mileage slightly, but got a performance gain to go with. I'd do the add-ons for that combination.

 

[jdw174]

JDW174,
Let me clarify what I was trying to say. ?

VT, I understand what you were trying to say, and I wasn't offended by it. ?I wasn't talking about adding a $250 air cleaner, simply the element, and a lower restrictive muffler to go with it. ?I don't have a heavy foot...outgrew that a long time ago (and spent 23 years of my life writing tickets to those that did ?I'm just always looking for an edge...at reasonable cost of course

 

[MI_99XPL]

VT Hokie,
I was reading though your clarification and I agree with you. Miles per gallon is primarily related weight and power, plus a few other things. But.... a dirty or restrictive air element does reduce power, lowering your mpg. And "most" aftermarket exhausts reduce backpressure, which enables the engine to make more power. Again, helping out with mpg.

So really what you were saying is that while the easiest method of improving your mpg is light, easy driving and regular maintenance, air elements and exhaust mods can also help if they reduce weight and make more power.

 

[tomsr]

General Motors posts the rated MPG on the window sticker. I have found over the years, they are pretty close. Why would they report otherwise? The customer knows up front, the kind of milage he or she should expect. Of course driving habits, and conditions have an effect, but not a dramatic one. Now if you were shopping, and looked at a Ford or Chrysler product, about the same size,with about the same engine, rear end, and equipment, GM has the best MPG rating-Hands Down.

 

[Sunshine_Kid_01]

VT Hokie,
I was reading though your clarification and I agree with you. ?Miles per gallon is primarily related weight and power, plus a few other things. ?But.... a dirty or restrictive air element does reduce power, lowering your mpg. ?And "most" aftermarket exhausts reduce backpressure, which enables the engine to make more power. ?Again, helping out with mpg.

So really what you were saying is that while the easiest method of improving your mpg is light, easy driving and regular maintenance, air elements and exhaust mods can also help if they reduce weight and make more power.

Thanks, yes, that is it exactly.

 

[jstrickl]

Not long after I got my Av, I installed the K&N drop-in replacement filter (not a FIPK). Late last summer, I also added the Magnaflow setup (muffler & tip). Just before winter, I added the HPPIII. Once the muffler got added, my mileage went down as I found myself needing to hear it Of course, as soon as the HPPIII went in, nothing improved in the mileage area as it is far to easy to "drive it like you stole it." Sorry folks, my mileage probably has increased, but since it's more fun to drive now, my mileage only goes up while on road trips. Around town and the to-work commutes are just to fun to open her up!

Jamie