ACERT Anxiety

:0 not to hijack-sorry to hear about your truck!

 

C12s arnt bad, I just wouldn't run one without a upgrade done to it. Is the acert a c13 or c15?

 

Don't be afraid of an Acert, they are good engines.

At one time they had a problem with the studs breaking, I would say its fairly safe to assume that the vast majority of them on the road have had the upgraded studs put in. If you buy one, take it in to have the overhead ran, they will be able to tell if it has the upgraded studs.

The only issue that other than the studs breaking is the wires for the coolant diverter valve, they are ran behind the oil cooler and pre-cooler and as a result get very brittle from the heat and break, it will throw a code when this happens. The fix is to reroute the wires out toward the frame and then up to the harness.

Having owned a BXS and now a NXS, I like the NXS much better. Throttle response in stock trim is far superior with the NXS, the BXS when it was hot out would feel lazy, still pulled good though. The differences between them is mostly sensor locations, and programming in the ECM.

When they are both driven properly, the 6NZ will nudge out the Acert on fuel, its not a huge difference, but there is one. The Acert likes lower RPM's than the 6NZ.

Mileage, keep the RPM down, they pull well down to 1150-1200, the other two, sadly we can't talk about those here anymore.

In order for this to be compliant in CA aren't you going to need to retro fit it?

 

From my driving experience with a C-15 ACERT, your MPG in that area will probably be 6 flat if your lucky, I would put it more along the 5.5 range. I drove one as a company driver and liked it, pre PDF motor, MXS, ran great, had tons of power and was reliable. Had the rockers replaced long before I was in it, had some actuators changed out on it and only left me stranded because of a stupid oil psi sending unit. The silicone deteriorated and leaked oil and the sensor was reading 0 psi so the truck wouldn't run. Other then that, I liked it and thought it was a good.

 

Forgot to address the IVA's, most of the time that they throw a code is from the harness that plugs into the solenoid, these are not the best design, they have the tendency to wiggle in the socket from vibration, they will then arch and throw a code, its not a real common problem, but it is still one. There are updated plugs that can be spliced onto the harness to cure this, but Cat has not started to produce harnesses with these plugs already on them. In 8 years of owning two different Acert's, I have only had to replace an IVA solenoid twice, once per truck, and one end for a harness. My last truck went just over a million miles with no problems from the harness, so its not a terrible design.

Another thing that can cause fuel mileage issues or performance issues are the bellows, or expansion joints between the turbos, if they are not aligned properly they can crack and as a result will loose boost pressure.

 

Buddy you put a dpf behind that accert and you can be assured you'll go broke. The worst I mean absolute worst resale motor is the 2009 accert dpf motor... There is a reason they are so much cheaper. Sack up and spend the money on a 2012 and newer def motor. Youll feel the pinch at first but be much happier after a couple years. God I'm glad we don't run CA.

 

I have a 05 379 c15 MXS acert, I've put 300k on it in the last 2 yrs. I bought it as a 475 HP had it turned up to 550+. I pull a bull rack so my mpg sucks, 5 to 5.7, I drive at 67 mph on interstate hwy & 60 on 2 lane hwys.
I've replaced 1 vva, 2 vva sensor's, and ran the rack 3 times.
I love the power n torque, the twin turbos provide nice bottom end response. From what I've been told these engines are very well built on the bottom end and 1 pc pistons.
The biggest concern I have is the expense related to Cat parts n labor, considering I'm at 900k now and an in frame runs $20k - $30k.

If you have specific questions I'll try to answer them if you post any.

 

The fleet I work for had a C-13 ACERT. Never had many problems with it in fact, over all the Series 60's with DPF's on them and the 2012 DD13's it was the most reliable. Having said that, I would go with the 6NZ or 3406 motor. But running I-5, that will be a problem in Cali and like Bigjls1 said, if you put a DPF on it you will ruin it. Look at the 07-09 ACERT motors. They are cheeeeeap! Nobody wants them because they don't work!

 

Yellow paint is pricey, replacement parts are obscene. I've overhauled quite a few of these, serviced and repaired even more. I've seen melted harnesses (inside and outside the engine) from underhood temperatures; leaking bellows between the turbos (as previously mentioned); broken exhaust manifold studs; low liner height, liner flange failures, and countless blown head gaskets; cracked heads and failed injector cups; failed rocker arms and shafts; I could probably say I've seen everything fail once, except for the bottom end and lube system. That doesn't mean it's a bad engine, they all have shortcomings. But you have to understand they're various issues and decide yourself what you're comfortable with. In my experience, this engine lugs down low, punishes an aggressive driver with bad fuel economy, but pulls like a freight train WHEN IT IS SET UP AND MAINTAINED PROPERLY. Use quality lube and filters (Cat 1R-1808, not a Fleetguard LF691A), keep your air filters clean and replace your mufflers regularly (a Donaldson M100465 is cheap), these engines need to breathe. Keep your rad clean, and maintain the cooling system! If it isn't already, get it re-rated to 550hp. If that isn't enough, buy a Steinbauer. The re-rate and Steinbauer will pay themselves off in fuel economy savings, if you respect the engine. Don't rev it up, yellow engines don't like it. Practice progressive shifting. And lastly, it gets real good fuel economy if it isn't running, so don't idle and keep your money in your wallet!