09 prostar horrible Mpg

[Waterloo]

(05-23-2019 )earnies2 Wrote:  

(05-23-2019 )Waterloo Wrote:  I'm wondering what the oil pressure is like? Having seen the work my dealership did and hearing your story brings back ugly memories. And I would bump the HP down, unless you are hauling 100,000 lb loads. And like Nick said, a pyro and boost gauge, and never lug the motor, keep the rpm's up. I bet they dry started the motor, that is what my gut tells me by your description of how it was running when you got it out of the shop. The mileage sounds about right though, I get 6 mpg all day long pulling a dry van with a mid roof, no fairing. 18 speed with 3:42 rears. I have a factory 600hp set to 485hp, Rawze did the tune.

My oil pressure is 20 idle and 45-47 going down the road. What should I put the hp at 475,500, or 525 I have a pyro and boost gauge and watch them constantly. I run down the road at 1450 to 1500 rpm I pull most hills at 1400 to 1700 rpm. Since the work was done I did change all 4 actuators and 1 injector I don't. run heavy I always try to run as light as possible usually under 30k on the deck. Do you think a new set of injectors would help? I'm only suggesting this because I have already had a problem with 1.

If you are running light, I would lower the HP for the extra fuel economy that offers. Sounds like you are doing everything right... As far as injectors, if they are the original and up there mileage wise and one or two fails... I put a full 6 pack in. When I do otherwise, bad things happen, no matter that part. And like Rawze said, that oil temp seems a bit high. I replaced my oil cooler at around 700,000 at the first in frame. They didn't by chance replace yours when they were working on the motor? Not saying it is bad, just wondering.

Oh, your damper, that is a wear item, Cummins recommends replacing every 500,000 miles. Something to put on the list if you have not down so already.

Just another thought, is that your trailer? If it is, have you checked the alignment on the tandems? Maybe they are out a bit and are causing issues with your fuel mileage? Again, just a thought, but I am thinking you should be doing a bit better on your mileage.