ok so i have a 2003 dodge 1500 3.7l with 22s on it and the gas mileage sucks.i know the 22 are not helping.just curious what everyone else is getting.im getting 12mpg
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2003 3.7l gas mileage
dodge on 22s
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My mileage has been sucking pretty hard here lately. I used to get 18-20 mpg no problem, but lately it's been 16-17.5. Plugs have recently been changed from ngk iridiums back to stock v-power, clean air filter, and ran fuel injector cleaner all w/ no effect. I've never seafoamed a vehicle but I'm thinking about it now. All my maintenance is up to date and the mileage has been down for a good while.
I would love to see 18-20 mpg! Mine increased after the tune up, air filter and throttle body cleaning but I don't think it was quite that good lol! I've never Seafoamed a vehicle myself, either but I'd be curious to see how it works for you if you do it. Do you do a lot of stop and go city driving? My mileage sucked when I did but now it's mainly highway and I see a difference.
- Cajun
- Cajun
It's mostly highway, to and from work 60/40 or 70/30 highway/city. It's just odd b/c for a good while I was getting 18 and up consistently even w/ more city driving. I'm trying shell gas now for a couple tanks to see if that makes a difference, then seafoam before my oil change if the shell fuel makes no difference.
Seafoamed my truck today hoping it would help with my gas mileage since all other maintenance is up to date and it's been down for a good while before the winter blend fuel switch. I put a little over 1/3 into the vacuum slowly letting it pull in at idle and the rest in the gas tank. Started it up 5-6 mins. later and saw a little cloud as I pulled away from the driveway, but nothing more after that for a 15 min drive holding about 3k rpm the whole time. I hope it helps the mpg, I've done fuel injector treatments w/ regane regularly so I don't think the injectors are gummed up.
If you didn't get much smoke, sounds like you're running pretty clean. Might consider cleaning the throttle body if you haven't already, that really helped my mileage and I did that at the same time as the tune up and air filter replacement.
- Cajun
- Cajun
Yea, it was really just a puff as I pulled away from the driveway that I saw in the mirror, probably just the seafoam burning off. The TB should be good as the last time I pulled and cleaned it there was really not much on it. I guess my next steps are going back to an 87 tune or back to the stock tune, and then maybe swapping out the 180 t-stat for stock if I don't see an improvement.
Well keep us posted because you've already tried everything I would suggest lol but I'm curious as to why you're not getting what you should and from the sounds of it, you keep your truck as well maintained as I do.
- Cajun
- Cajun
Well, I've reverted back to an 87 tune and my mileage is still sucking. Got a record low today of 15 mpg, I've never seen it that low in the 35k miles I've had the truck. I'm at a loss here, maybe I should change the t-stat back to stock and put in some iridium plugs like I had before. It's gonna take awhile for me to get through another tank since I'm not driving it a whole lot, but if it's low again I'll swap the t-stat and if that doesn't help I'll go back to iridium plugs.
Wheel alignment is fine as far as I can tell from tire wear and handling. The tire pressure is checked regularly, oil is correct 5w-30 for my 04, brakes are still stock, plug coils should be fine no codes/misfires, and the route is pretty much what it has always been. :thk:
How often do you drive your truck and, on average, for how long? Do you consistently get it up to operating temp?
- Cajun
- Cajun
It was my daily commuter for about 45-50 miles which were mostly highway, so it go up to temp. Now since I had to quit that job due to physical problems I don't drive it nearly as much. I've went ahead and swapped the t-stat back to stock while I was changing out my abs sensor the other day, so maybe it will get better. I noticed a slight drop after initially putting in the 180 t-stat, but it was only like 1-1.5 mpg so I'm skeptical of just blaming the bad mileage on that.
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a 180 tstat is possible to cause a slight mpg drop. if the engine doesn't get to proper running temperature it will run in cold enrichment road and run a little rich. I'm a big advocate of using 180 tstat's, but there are circumstances when they cause problems like you may have.
I don't think getting up to temp. was the issue, I easily got it to 195 w/ the 180 t-stat. Maybe the 3.7's just aren't efficient w/ 180 t-stats, hopefully this solves it. I'll report back after a few tanks.
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Keep in mind that not only does it need to get to operating temp, but it needs to remain there. Do you know for sure the temp of the coolant or is it approximate? There's a good chance your coolant temp is hanging around 180-190 if that. Especially if you run the AC a lot (I think the v6 rams have an electric fan in front of the radiator for the AC condensor)....this would cool it even more. Just something to keep in mind. If you have a 180 tstat then normal operating temp should not be 195, it should be close to 180. Stock normal operating temp with a 195 tstat is about 195-200.
The newer 4th gens have only an electric fan on the v6. The 3rd gens like mine have a separate radiator/condenser for the AC which has an e-fan and a clutch fan for the radiator. I've done a lot of bolt ons to the truck and when it was stock w/ the clutch fan it ran about halfway up the temp gauge on the dash and always got 16mpg. Comparing that to the readings I get now from my aeroforce interceptor for coolant temp show halfway on the gauge to be about 200-210. It really only got in the 190's, maybe 200 if I was sitting for awhile w/ the 180. When I didn't yet have the interceptor and put an e-fan on the truck I set the controller using the gauge on the dash to come on a little over halfway. W/ that setup and the stock t-stat I was getting 18-21 mpg consistently. I did several other mods, none of which effected the mpg and finally did the 180 t-stat as advised by hemifever for the tune he wrote for the truck. W/ the 180 I saw mileage drop down to 19 max. For some reason the mileage just kept slowly falling for the next 1.5 years, now I'm back to 16-17, 15 on the last tank (maybe bad gas). I'm at the point of having only a couple things left to try to get it back to where it once was.
I don't think it is. I stopped running the 93 tune a month or two ago. I'm running an 87 tune, I think the only thing modified in it is torque management which is non-existent in my manual tranny truck to begin with. The only things I had left to try were the thermostat and going back to iridium plugs. Thanks for your input.
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new here figured i would report on this i have an 06 manual when i first got it I was getting about the same as you mileage wise
this is what i have done and my gas milage has jumped way up 16-17 in town 21-23 hwy
air raid cold air intake system
high flow cat with cat back exhaust
bully dog programer
iridium plugs
the most noticeable thing i did was the intake and exhaust but i cant complane about my gas milage now and a noticipal power increase
this is what i have done and my gas milage has jumped way up 16-17 in town 21-23 hwy
air raid cold air intake system
high flow cat with cat back exhaust
bully dog programer
iridium plugs
the most noticeable thing i did was the intake and exhaust but i cant complane about my gas milage now and a noticipal power increase
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