Air Filter replacement dropped MPG

b4tn · April 4, 2019

I did an Air filter and oil change this weekend. I used the same oil I used last time STP 0W-20 Dexos but autozone was running a special for an air filter bundled in so I went ahead and put in an STP air filter as well. I am used to getting 18mpg in traffic and 20-22 on the highway but suddenly I am getting 13-14 mpg since changing the air filter. Anyone else have issues with the STP brand filters? I am not in the market for a CAI but thinking about getitng a K&N or AEM drop in now.

Arch Angel · April 4, 2019

I went into a K&N drop in, no MPG change or anything really same old same old. ..i can't see an airfilter changing your MPH from 18 down ot 13/14 there has to be something else wrong i could see 1 maybe 2 mpg AT most..check installation of air filter maybe it's in wrong? i get 18-20 city and if i do all highway at 70-75mph i get 26-28 in my 5.3l V8 Crew cab

massachusetts area. so hilly terrain

Grumpy Bear · April 4, 2019

It might not be the filter. Sometimes while change it the MAF sensor gets dusted up pretty good. Cleaning it can restore balance to your universe. Worth a try, eh? There's a spray for that.

Arch Angel · April 4, 2019

1 minute ago, Grumpy Bear said:

It might not be the filter. Sometimes while change it the MAF sensor gets dusted up pretty good. Cleaning it can restore balance to your universe. Worth a try, eh? There's a spray for that.

Sounds like a STD or something...LOL seems legit tho.

Jacoby · April 4, 2019

I agree with grumpy. Give the MAF sensor a cleaning and see what happens. No way a new clean filter dropped your mpgs

b4tn · April 4, 2019

Thanks, I will give it a cleaning this weekend.

EpicLT · April 4, 2019

1 hour ago, Arch Angel said:

I went into a K&N drop in, no MPG change or anything really same old same old. ..i can't see an airfilter changing your MPH from 18 down ot 13/14 there has to be something else wrong i could see 1 maybe 2 mpg AT most..check installation of air filter maybe it's in wrong? i get 18-20 city and if i do all highway at 70-75mph i get 26-28 in my 5.3l V8 Crew cab

massachusetts area. so hilly terrain

How? What have you done to your truck to get those numbers?

Arch Angel · April 4, 2019

51 minutes ago, EpicLT said:

How? What have you done to your truck to get those numbers?

Nothing? stock LT 4x4 crew cab - i drove from Central MA to bronx NY all highway measuring MPG and was getting 28.6mpg going 75-80mph sometimes downing to 70mph clearly speeding (limit in most area's 55-65)

-- should also note rear of truck was filled with vacation stuff ~ give or take 400-500lbs of junk including coolers/food/etc

-- inside vehicle was myself heavier guy 390lbs at that time (lost weight now down to 250 woo) wife 160, son who was like 20lbs. and random junk inside cab.

i drive regularly to NH/Maine and get 26-28 depending on day/weather etc.

Normal cheap shell gas .

Jacoby · April 4, 2019

No way youre running 80 and getting that kind of mileage. No way

3tspapat · April 4, 2019

His SN checks out...it's pure magic bro...

Darksky · April 4, 2019

Arch Angel, can you come wave your hand over the hood of my truck?

BIGDOGx · April 4, 2019

1 hour ago, Arch Angel said:

Nothing? stock LT 4x4 crew cab - i drove from Central MA to bronx NY all highway measuring MPG and was getting 28.6mpg going 75-80mph sometimes downing to 70mph clearly speeding (limit in most area's 55-65)

-- should also note rear of truck was filled with vacation stuff ~ give or take 400-500lbs of junk including coolers/food/etc

-- inside vehicle was myself heavier guy 390lbs at that time (lost weight now down to 250 woo) wife 160, son who was like 20lbs. and random junk inside cab.

i drive regularly to NH/Maine and get 26-28 depending on day/weather etc.

Normal cheap shell gas .

You must be driving downhill with a tail wind and in v-4 mode to get over 25 mpg. Sorry these v-8's while damn efficient are not that efficient. Not saying your lying but your wrong in your calculations imo, though it seems many people like to embellish their mpg numbers on the internet for some reason. I get a good chuckle when i see other 6.2 owners talk about 17-18 mpg in city driving lol not a freaking chance in hell!

To the og poster, maybe the station you went too just changed blends from winter to summer?

Arch Angel · April 4, 2019

35 minutes ago, BIGDOGx said:

You must be driving downhill with a tail wind and in v-4 mode to get over 25 mpg. Sorry these v-8's while damn efficient are not that efficient. Not saying your lying but your wrong in your calculations imo, though it seems many people like to embellish their mpg numbers on the internet for some reason. I get a good chuckle when i see other 6.2 owners talk about 17-18 mpg in city driving lol not a freaking chance in hell!

To the og poster, maybe the station you went too just changed blends from winter to summer?

HAHA nah , i assumed with the V8 on my trips i'd get 20..maybe 22 max highway while driving and stopped at rest stop for food/gas i looked at calculation it came out ot 28.6 - i did the math after fill up and it was about on par my math came out to 28.7something or other

I was probably in V-4 mode alot as i coast/drive the same speed i don't speed up/down a lot. i normally get up to speed and just cruise at that speed. and plan my trips around dodging traffic.

combined i get between 18-20 give or take. towing my boat i get 16-18

Mike GMC · April 4, 2019

To the OP, did you forget to reconnect the MAF sensor? If you do clean it, be very CAREFUL with it. The little wires in it are very fragile. If you buy a cleaner spray, spray it at arm's length, not close up.

To the MPG conversation, I just did a family road trip, Denver to Galveston and back. Almost 2300 miles. I averaged just over 20 mpg round trip. Most of the trip, I was on cruise control at the speed limit plus 5. There must be some secret I don't know, but there seems to be no way to get much more mpg out of mine. I'd love to see even mid 20's, but high 20's seems suspect to me.

Coming down to Denver from the mountains I did get my best 50 mile average up to 34.5, but that was literally down hill pretty much all the way at 5-6% grades.