Ok,

With diesel well on its way to being $6 a gallon ($1.549 per L) most days I have to do what I can to get this truck to be more fuel efficient. And I need your help.

I recently replaced the aged Yoko Geolander AT's 285's (bald and badly uneven wear due to poor alignment) with Toyo MT 285's - nice tire but deep tread blocks offer considerable sway on heavy breaking and hard acceleration.

Here's the thing, my mileage has dropped WAY down. In the next week or so, I am planning on doing a complete drive line and transmission service with Dodge products - should I return this stuff and get product elsewhere? It already cost me $200 for Trans, Diffs, T-Case and a set of front brake pads.

I adjusted the tire height with the installed tire on the truck using my Smarty Box. This has proven to be interesting since it now seems I'm going a lot slower than most people on the HWY. I will address that with Dodge later on using their scanner.

My overhead computer is nearly 40% out of whack compared to hand calculated economy / mileage and is bad news.

I am looking at installing an exhaust manifold to assist in cooling my EGT's down some as I'm worried that this heat from slow launches (no or little smoke) is spoiling my economy. Will this be money well spent?

I'm looking at adding a compound HT3B set up to my truck to lower the EGT's and get more air in their but this is proving to be a little too pricey at the moment.

I've tried no using my Smarty, I've tried it on 2 and 4 along with my COMP on 1x1, 1x4 and even 3x2 and 3x4 (pump wire not connected) and there isn't much noticable change in mileage. I'm considering removing my Stage 5 injectors (Jammers) but I'm hesitant to do that. I'm also wondering about timing issues - if I ran the COMP on 1x4 and the Smarty on 3 would I be hurting anything? I tried running the no COMP and the Smarty on the fuel saver mode but the truck doesn't even roll - it stalls out and quits as the pump doesn't deliver enough fuel I guess at that point.

Then there are things like adding a topper or cover to the back. Does this work? I already drive the truck really easy in stop and go conditions because its bloody expensive but this isn't working either.

When cruising, no load, flat ground my EGT's are about 350 F and boost is around 2 pounds. When I stand on it (HARD!) boost climbs to 33 pounds easily but the EGT's rocket to 1250 F even faster.

I am looking for assistance in getting this figured. What have people tried or would you stay away from etc. This topic I'm sure will be an on going thing with the cost of fuel climbing so let's get the replies rolling.

Thanks for the help guys...

 

i get my best fuel mileage on 5x5 believe it or not. mine is a automatic not 6er but i have 285's and i get about 19mpg hwy hand calculated cruising at 72mph. when was the last time you changed ur fuel filter or cleaned the IAT sensor? my truck dropped to 12-14mpg mixed driving when the vp was on its way out.

 

My VP isn't new by any stretch but it still holds good pressure. WOT is about 14. I cleaned both the MAP and IAT last Friday and will swap out the fuel filters for ***** and giggles.

I don't see injectors in your signature and if I set mine up there boy it will smoke... I also have issues with my OEM HX35 - too small, I know I need twins, I just can't afford it.

 

How about swapping back to the stock injectors?

 

See now that's the problem with cores, now isn't it... I don't have them re/re.

 

4x10 injectors , Suncoast Triple Disk , Pro Loc Valve Body , Super B Charger , ATS intake and Exhaust Manifolds , BHAF , Air Dog

21.3 MPG

 

Drop down to some smaller injectors like a 75 or 100hp.

 

i gained mileage with my 150's, the 285mt's dont help you at all, tap the pump it will help your mileage, by increasing injection timing, this is why you are not seeing changes with the comp and the smarty, it will help like you wont believe, if you have a good fuel system setup you will be fine tapping it. DD

19.2 around town drivin like i stole it!!!!!

 

Any progress on this?

 

No. not really. I'll close it for now.