My Mercer Experience 8-31-15

And I'm not a chrome guy either. I'm more of a flat-black kind of guy. I don't like chrome or chicken lights

 

I average 5.2 in my cascadia. My friends identical cascadia averages 5.6. You can do that in a hood truck. There are hood trucks getting upper 6's and low 7's. It's all in how you set it up. If you get a hood with a c15 turned up to 625 with a 10 speed with 3.70 rears, you can't expect 6mpg. With that you couldn't expect 5. But, you get a hood with a 60 series, 13/18 speed, 3.42 or 3.36 and tall 24.5s then you should be in the 6's. I would be willing to go out on a limb and say that the set up plays a bigger part than the aerodynamics. If you put the same exact set up in an aero truck and a hood truck would the aero truck be better? Absolutely. But too many people see a hood truck and think that it has to get horrible fuel mileage just because it's not curvy. The next time you see a 389 with the Fitzgerald sticker on the side, ask them what they average on fuel mileage. Out of the people I've talked to, they average around 7.1 in a hood.

The point is, I don't want a newer truck. I don't want DPF or DEF. The fuel mileage on these older trucks is going to be worse than a new truck either way for the most part. So, if I have to have worse fuel mileage either way, I might as well have it in the truck that I want since I'm the one paying for it.

 

Both of ours are 2009 with the DD15, 10 speed, 3.36 rears. His had about 609,000 when he got his. Mine had 653,000. We've both been trying different thinga to try to increase the mileage. We both got overheads which didn't really help. I gained a tiny bit after taking the top off of mine. He hasn't taken his off yet. They've both been hooked up on the Detroit software and had the injectors, egr, turbo actuator, and everything you can test, checked. Everything checks out. The only thing that I've been told that could help it is doing the EGR delete. He said he would do it for $1800 and if I didn't like it or it didn't help then he'll give me my money back and put everything back to normal.

 

That's just the thing. It feels like it has no power at all. It's turned up to 506hp and still feels weak. I think the rear gear is just too long of a gear. Its too hard for the truck to turn that gear, especially pulling hills, so it uses more fuel. Running somewhere like texas, oklahoma, etc where it's relatively flat would probably be fine but not in the south and east with all of the hills. I should have gone with a 3.42 or 3.55 but on paper the 3.36 worked perfectly. Once I recover from the hit I took fixing it, I'm going to do the EGR delete and see if that helps. I know it will help but I just don't know how much it will help.