Well, I took the truck in to the engine shop to get new injectors installed and they put it on the dyno before and after.....

Pre-Injectors it made 398hp to the wheels

After Injectors it made 401hp to the wheels

The guy at the shop was amazed seeing the engine is a 430hp motor. He said he has not seen a truck do this well even NEW. He stated the new DD15's at 505hp only put down about 435-450 from the factory.

I was quite happy with the overall job, and they did it all in 1 day which amazed me seeing the FTL Dealer was 2 weeks behind on work. So if your ever in the Gary/Chicago/Milwaukee area: Indland Power Group is a great bunch of guys. I used the Gary shop since it's only 35 miles from the house.

Oh, and seeing I pull empty trailers, I had them turn it back down to 370hp cuz while driving in a rain storm last week in Houston, the damn thing kept breaking loose and I got basically new tires on it. Todays snow storm should be lots of fun

 

How was the higher horse power getting your trailer "break loose" and why "practically new tires" are a part of this? Unless you were driving at 100 MPH

 

I honestly dont know. Every damn light I came to I had to walk the throttle to stop from spinning the wheels. I pull a basically empty tank, so there is NO weight on the rear axles at all really. Scaled with full fuel tanks and the trailer loaded I gross out at 32,150lbs with only about 12,500 on the drives. My tires are at 25/32 so it wasn't because of bald tires like so many trucks I see down there with. And even at 60mph, I could put my foot down and the thing would spin. I think it had to do more with the amount of rain and oil coming up on the road, but it was like driving in a ice storm, which I'm getting ready to do now LOL

The 370 setting won't make any difference with this I know, but I am hoping to gain some MPG, seeing I could pull these loads with a dully pick-up truck really HAHA!!

 

I must have missed something. If you only picked up 3 hp, why did you change injectors?

 

Now I get it. I had the same thing after I had my CAT dyno-tuned and had 3.73 axle ratio coupled with 295 low profile tires. I would cruise at 58 MPH and I had so much torque at the wheels that going uphill in Texas I remember feeling the truck's drives going sideways! After I changed the axle ratio to 3.42 all became normal. Instead of reducing the horse power I think you should do something about your rear ends: your RPM will go down, the torque at the wheels will go down and you'll save on fuel.

 

Try starting off in the granny gear. Feather it more.

 

Torque is your friend when it comes to fuel economy. You just need all your components in synch to be able to fully take advantage.

 

i drive 550ixs rear axle 4.30 rear tyres11r22.5 and had cummins tech from austrailia come for trip with laptop and improved performance heaps that at 15000ks from new .i think dynos out of date tune under loaded driv e conditions .ther again i just dumb driver from near antartica haha just my spoke in the wheel .

 

Mine did that, until I replaced all the bent rims.

...............

 

I had a bad Injector and it was only a couple bucks more to replace all 6 with the promo Inland Power was running. $2,245 installed with overhead and dyno-tune included. Freighter wanted close to 3k