3406E vs C15

I dunno,.. I think the Pre DPF ACERT is a great motor.

Like I've said in countless posts,.. I have not had a single mechanical failure or break down. I bought the truck with 994k mi, I'm now just over 1.2 million mi.

Mine is the BXS with 435hp. Not as strong as the 475hp and later DPF versions. Mine is in the shop now getting upgraded to 500hp. Mufflers, Injectors, turbos, fuel system is all being gone through. The emphasis for my upgrade is not for the power,.. though I will certainly not cry about it,.. the make focus is to improve fuel economy.

If mine blows up, I'll rebuild it and should be good for another million.

Hurst

 

What year? Our problem child is an '05 475 hp (the 6nZ is 435 at least so the sticker says). My neighbor has an '07 and he says hasn't had any of the VVA problems.

Cat house in Thunder Bay, ON told me to get the ECM re-flashed with an update of some sort and it will eliminate the VVA low oil psi problems. All the re-flash does is lower the acceptable oil pressure limit so the computer doesn't throw any codes. The oil pressure is still the same as before the re-flash.

 

I had a lot of issues with Iva and vva's in an '05 ACERT. If it was me having to choose between the 2 I would go with the 3406e based on my experience between them. Fuel mileage is too much of job and set up specific variable to predict just based off the engine manufacturer and model series. I'd go with the 3406 for the reliability and overall "bulletproof-ness" of those engines compared to the more modern yet more complicated ACERT. If you really can't decide then go with a 6nz prefix c15.

 

I'll just 3406e or c15 cheap and rebuild it myself.

 

My truck is registered as an 05, but the build date and engine are 04.

I had an issue with low oil pressure and it would set off a check engine light and code showing low voltage for an actuator.

No problems were found under the valve covers. Had the oil pressure sending unit replaced to see if that was a problem before going after the oil pump. That resolved the problem, and have not had a check engine light come on since last July. Besides a couple coolant hoses failing,.. the only other issue I have had is a safety sensor under the clutch that shut off my cruise and jake. Sensor replaced,.. all has been well. These are issues with the truck itself and nothing to do with the C15 itself.

My oil pressure gauge shows 30 PSI at idle and 65 - 70 PSI above 1000 rpm,.. regardless of load. The only variation I see is when the engine heats up climbing a hill,.. anything over 200f and the oil pressure drops to 55 - 60 psi. Once the fan kicks on and it goes back down to 180f,.. the oil pressure returns to 65psi.

Hurst

 

Yes that is the same problem I had only I had it many, many times. Sometimes I wouldn't get 5 miles and the CEL would be on again. A new wiring harnesssolved the problem for a while but now it's back and de-rating. Sounds like your computer has been re-flashed to open up the oil pressure parameters. I hope they made sure you have the updated VVA housings when they were in there..

 

Fuel mileage wise, I'd have to say it's pretty much a wash between the E and a 6NZ. Neither one is likely to win any awards for most fuel efficient though. Even if you find an MBN (Bridge) Cat, some will easily take the 6NZ files.

 

Rollin coal has it on his mbn. My dads cousin has 06 acert and has million miles without any breakdow .

 

Back in June the hot lead for the ECM corroded off. Cleaned the battery cables and reconnected the ECM hot lead,.. only to have the ECM completely fail 2 weeks later. That was an expensive break down. Far as I know, they copied over what ever the original ECM was, reprogrammed the injector codes and charged me $100 to test drive a truck that wouldnt start. All said and done with towing,.. that set me back $6200. Thats been the most expensive repair to date.

I've had the top end adjusted twice since I've had the truck. None of the notorious ACERT issues have plagued this motor since I have owned it. Been really lucky so far.

Hurst