Calling all CAT techs. Answer this question.

The thing is I only touched 1700 maybe twice all trip. That was getting up to speed, going up a steep hill with a heavy load, and only bumped it in 9th before shifting into 10th. That was to keep from lugging in 10th and not get ran over from traffic while pulling up to speed.

I think all of the '08 Petes they have are getting somewhat similar mileage problems, but not quite as bad. The sticker on the intake reads that this engine is a CAT followup engine. It states to not do any maintenance before calling CAT and consulting with them first.

I don't know if they mean for the life of the engine, or until warranty is out. This truck already has 358000 miles on it.

 

I would have to guess that the motors were or are a test bed for CAT. There really isn't anything else that you can do besides what we have posted. The only other option is if your boss or the mechanics decide to do something cause its gonna cost money and they are the ones that probably know whats going on with the "followup engine stuff". Best of luck to ya and sorry I couldn't help more.

 

I know a CAT tech that did ecm work on the sly. He knows me and my operation, so he felt safe doing the changes. I don't know exactly what he did, but I do know he messed with the heavy haul program that I already had in my ecm. The changes he made didn't void my warranty, but did bring the motor to life a little more. Sorry I don't know the specifics.

As far as the fuel pressure, I'm getting up towards 20 psi more than stock. If you want better mpg's you need to look at high flow mufflers, maybe the FASS system and definte ecm changes.

 

thank you pullingtrucker for the info, so far could not find anybody who could do any changes, CAT dealer told me that everything in withing specs. as far as mufflers go i have single resonator underneath and straight pipes.

 

I agree. I wouldn't go playing with fuel wires etc untill you fix what is actually wrong with the engine first. It sounds to me like the sort of work your doing a 6NZ C-15 would probably get 6-7mpg, you're getting 3.5mpg....no amount of emission crap should double the fuel consumption.

What temp is the exhaust running at? you may have an exhaust blockage somewhere, plugged cat or DPF, just cause the ECM thinks everythings ok doesn't mean it is, it just means the ECM can't see a fault.

What is your serial number? I may be able to give you some info on the horsepower settings.

 

Serial # 8CPXH0928E1X

Engine Model: EMY 2007 C

No pyro or anything good like that, just readout on dash.

 

Thats not a CAT serial number, that looks like an engine family number. The Cat serial number will be a 3 digit prefix followed by a 5 digit number eg. 6NZ12345 or SDP54321 etc.
No pyro is not a good thing, it make diagnosing engine problems difficult. May need to take it to a dyno so it can be checked over properly.
Like I said, they are known for poor fuel economy but not that bad.

 

Thanks. I will check when I get to the truck again. That number was on the front cover. But I will check further.

 

check your charge air cooler may be leaking will cause poor milage and poor pulling power

 

It turns out this truck has an expermental engine installed by Cat, and is supposed to only be serviced by Cat.

I was told this has been normal mileage since this engine was installed.