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Mpg thread just for 3rd gens

17K views 136 replies 36 participants last post by  Gator1 
#1 ·
Been searching for a mpg thread specifically just for 3rd gens. I caint find one at all!!! If not we should start one. I'm trying to go for the most milage possible with my truck and want all info on how to get. Even little stuff like intake nd exhaust manifolds. Do those help?? Witch tunner gives best mpg gains?? I heard some people with smarty gained 2 mpg others stayed the same. Bully dog people claim they see 4 mpg gains but there gauge setup sucks compared to smarty touch.
Also witch injectors give best milage? I heard nothing but nice things about flux Injectors?? This true? Also do cai actually help these trucks? Any real world milage calculations are a huge plus. I average 17 mpg with the truck in my dig and want to get it high as possible.
 
#3 ·
If your doing 17 mpg with a MC leveled & 4" straight pipe, your doing pretty good already.

Your best bets right off the bat are stock airbox, 4" exhaust with CAT or Aero 4040 muffler where the cat would be, silencer ring in place and the android app Torque (or equiv) to monitor whats going on day to day. I use it daily on every drive.

A 200*f stat, EFI live or HPTuners (to adjust the fan on temp to 40*f, keeps the fan clutch disengaged for IAT/ABT temps) and a cheap marine grade front cover to block some of the front airflow to get IATs up. 100*f and up is good.
 
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#7 ·
My rpms on this truck at 70mph are 2200 witch I think I realy high considering my 02 6 speed I had was at 1900 Ik bout the 06 g56 having a shorter 6th gear then 07 on up but dam it sucks I heard people went to a 285/70/17 and gained 1.5 mpg because lowering the rpms but it makes no loical sense.
I did take the silencer ring out, does that hurt milage taking it out? If so il put it back in!! I just heard everybody always taking them out.

I also use 2 stroke 16 ounces to every fill up to help prolong me buying new injectors cuz I have 210,000 on this truck.
Will actually be switching this cobbled together 4 inch exhaust out for 5 inch cuz I like the sound better, hate how it raps!!

A Marine grade front for the grill?? I do notice now that it's colder highs in the 40s now here in wisco. That the coolant temp stays down aways. It does have a 200*f t stat in it. Here in Wisconsin we see temps down to -50 some February days so keeping the truck warm is a struggle to say the least nd Ik milage will drop considerable cuz of lots of idle time cuz I work out of my truck. (Logger)
 
#4 ·
custom tuning (udc pro w/your touch) and a low stall TC have been my best helpers.
I need more tanks to give an ave. but i see 18~mpg empty @ 25 to 55 mph.
 
#6 ·
I'm going to add something I just found out this past month. I just got back from a 2500 mile trip pulling my 10k camper. I went from Denver to Kansas city, then to Fort Worth and back to Denver.

I put my truck back to the stock tune and averaged 11.5-12.8 hand calculated towing. When I tried revo sw3, driving exactly the same it dropped to 8mpg. Kind of interesting, there were no other variables, no wind, just flat highway pulling at 60-65. Next time I fueled I put it back to stock and went back up to 12.8. I did all of this on the same leg of the trip on the same day, needless to say I left it on stock the rest of the trip.

I drive for mileage most of the time since I'd rather get 400 miles/tank while on a road trip instead of 280.
 
#8 ·
I got 230k out of my stock injectors, just replaced them last month and gained 2.5 mpgs back. I've driven about 3000 miles with them. Tired injectors really affect fuel economy.
 
#10 ·
I gota wait till spring to replace them, that's when I have time.
But u went with stock ones??
Also I said somthing In Ur last post bout the silenceing ring in the turbo. I took mine out. Should I put it back in??
 
#11 ·
If starting war, and stick to 55, I once got 28mpg in a 9 hour drive. That same drive I usually drive like a grandpa and get 22. Once got 14 when was in a hurry.

Between 55 mph and 70 your mpg is literally cut in half.
 
#16 ·
18.5 mpg @ 65mph with rpms @ 2100

that's a light foot obviously

Smarty catcher 3 for now
 
#21 ·
My '07, as-is in my sig, gets 11-11.5 during the daily grind, mix of mostly city (ok, it's Wyoming. Town of ~10k) with some blasts out of town to my dad's house. Note that I'm not afraid to use the power, and do frequently; my tires can attest to that, they're almost drag slick worthy. It also smokes a LOT just putting around town.

Holding a pretty steady 90mph from Salt Lake City to Laramie, with a stop in Rawlins to fill up, she got the same 11.5.

Setting cruise at 70, and babying it and watching in the mirror and backing off when she smoked, from Laramie to Riverton, got a rock solid 17.
 
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#22 ·
My 2004.5 got 18 hauling a folding trailer from Spokane to Albany (Ore.) and back 65mph 100%. No wind resistance, just 2500 lbs of weight. From Spokane to Seattle and back, unloaded plus wife and kids, 19 - at 65-70. There's hills on that trip. In city, my last tank did 12.9 - but it goes up to 15/16 if I really take it easy and quit clearing out my trucks "throat" all the time LOL.

All hand calculated.

Stock.
 
#25 ·
Yea I'm Gana put it back in right now actually. Doing rear brakes on it as we speak. Already put 6,000 miles on it and only had for 45 days lol I travel a lot so every bit of milage helps my wallet and all repairs I do I can right off since I'm self employed 👍 And that includes mods!!! 👍
 
#29 ·
Silencer ring.. yes it does... stock turbo, hardly felt, modified HE351, yes felt more low end and mid range. Same for the fuel cooler.

I will move on and not bring this up again... BUT, if anyone wants a before and after and are in the neighborhood... offer is still open for both the silencer ring and the fuel cooler. If someone wants to foot the bill for dyno time, I will go test it.
 
#31 ·
Are you talking WOT more low end torque? I can change sw's and have a hard time telling 30hp/60ft of power difference.

If not wot then the power difference would be miniscule (my contention is that the power difference is none) and you would have to be doing seat-of-the-pants dyno with your right foot held in the exact same position/%throttle...paaaa leeez.

Just like your opinion, this is mine on the subject.

Sent from my SM-G900V using Tapatalk
 
#32 ·
Some people have done so many 'mods' that had 'positive' results of more low end torque and increased mpg that they should be making 1500ft/lbs and getting 40mpg. Lol

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#34 ·
Amen, brother.
 
#36 ·
Lol, every mpg thread that comes up, gildo and nemachinist show up with pure negativity, why, cause they get crummy mileage out of there trucks and dont kno why, therefore everybody must get crummy mileage also and are just lying. I love these guys! Meanwhile im killing it mileage wise! My last work trip, i had multiable trips from portland to the coast, hwy26, winding, hilly road. On my final drive back, i checked my trip meter and had gone 552miles and still had slighty over 3/8 of a tank left, lol. But of course, im lying!!! Farout to the pessimists!!!!!
 
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#40 ·
Lol. I don't get crummy mileage. I get 17 to 19 in summer with my 03 qcsb 4x with 285 duratracs on it, far from crummy.

my apologies for coming across with the negativity, lol, it wasn't my intention.

I have serious doubts about what people feel or think they feel. Call it placebo effect, or that people simply want there hard work on 'mods' to have some positive effect. I have my doubts.

Specifically about steve05ram, I don't think at all that he is bull shi-ing or a lyer. he does his research more than most but on these couple things I think he is wrong, i think he has thick enough skin to handle it. Just my opinion that's all.

Your claims(VADERPOWER) are a complete joke, but thank you for the laugh.


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#39 ·
Filled up today.460 miles 27.269 gals.16.9 mpg.That's right to the cap.Winter fuel is here now i believe.last 2 tanks its been dropping.Avg for the last 3,143.491 gals is 16.5 mpg.Best since i started keeping track in 2012 was,218 mi 11.735 gal.18.6 mpg.I always fill right up to the cap everytime.
 
#42 ·
I hate these MPG threads...

1. Most folks are using the inaccurate overhead MPG indicator to share their MPG results.
2. Most folks have oversize tires and no mention if they recalibrated their odometer.
3. Most folks are quoting the maximum mpg they have ever seen or calculated.
4. Everyone gets better MPG than me.
5. The guys who say they did 552 miles with about 3/8th of a tank left. What kind of MPG math is that?!!

Carry on.. :)
 
#58 ·
I hate these MPG threads...

1. Most folks are using the inaccurate overhead MPG indicator to share their MPG results.
2. Most folks have oversize tires and no mention if they recalibrated their odometer.
3. Most folks are quoting the maximum mpg they have ever seen or calculated.
4. Everyone gets better MPG than me.
5. The guys who say they did 552 miles with about 3/8th of a tank left. What kind of MPG math is that?!!

Carry on.. :)
This is a big one. I wonder how many people have speedos that are 5-10mph off. I used a gps and the smarty to get it as close as possible on a recent 2500 mile trip. It takes adjusting it a few times every time you stop to finally get it right. My truck was only counting like 97 miles per every 100 driven (less miles on my truck :party018: ). Putting in your tire size gets you close but it still takes adding or subtracting a few 10ths to get it perfect.
 
#43 ·
I'll try to get this back on track since I guess I derailed it.

Contrary to much of what iv read here, I tend to get lower fuel economy with advanced timing. I think this could have to do with the +50 injectors. I get best milage with either #4 timing or stock.

Also I tend to get better economy with increased rail pressure but the going theme is that it's not worth the wear and tear on the cp3 and injectors. So I use stock rail pressure.

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