ddec ii to ddeciii/iv conversion

Good ? I too have a ddecII and have also wondered if it's possible to go to a ddecIII. I believe my FLD only has an OBD one port also, so I've still not been able to check/alter any of my ecm settings..

 

Biggest hurdle in the relucter wheel on the crankshaft is different, requires disassemble front cover to change. I believe their are a few other sensors that are different but that is the biggie

 

My suggestion is be happy with what you have!! However, if you are not, you can't "convert" your DDEC 2 ECM to a DDEC 3/4 ECM. They are two completely different animals. There isn't an aftermarket kit you can buy, no special doodad or gimmick & no magic wand you can wave to make it so. Somebody has provided you with bad, uninformed information. The only solution is this: you need to buy EITHER a newer complete DDEC 3/4 engine including all the wiring, ECM, etc for the specific truck you have & do a swap OR buy a truck that has a DDEC 3/4 engine. A little history: as you may or may not know, your DDEC 2 engine is a lower horsepower/torque engine--usually 370h-430hp with a max of 470hp. The torque rating is also lower @ 1350-1550 ft lbs max. Trucks with these lower hp & torque DDEC 2 engines usually ran 3.70, 3.90 or 4.11 gearing to make up pulling ability. 3.90 gearing was the most common. I'm not going to list all the differences between the DDEC 1/2 engines & the DDEC 3/4 engines as there are too many. However, this is the most important point I make---its a structurally weaker engine, both in block & head design as well as internal parts design. An example is the use of 2 piece pistons with bolt-on piston skirts. A STUPID IDEA!!! Therefore, all of the performance upgrades on the market are NOT available for the DDEC 2 engine. While the DDEC programming overall is pretty basic & simple, the DDEC 3/4 ECM is much more advanced than the DDEC 2 ECM.

 

18SP546 GOOGLE IT

 

DDEC II -- DDECIV wiring harness & hardware conversion. Nice, thanks for the info. I'll be checking into this..

 

The only one with bad, uninformed information is you. People upgrade from DDEC 2 to 4 all the time. Just because you don't know how to do something doesn't mean it can't be done

 

I am finding out my self that it is a bit of a challenge if the engine family main frame flash is not correct Detroit had to write a custom tone wheel input in order for my truck to fire and i am currently still dealing with all the other inputs and outputs for cruise , Jakes, fuel pedal and , service brake my old engine harness and ecm works completely fine but when i switched from ddec 2 to ddec 4 the computer is Loki g for inputs and outputs that are not on my factory freightliner harness due to the age of the wiring and minimal requirements for my old system back at freightliner for the 4th time to get the base program write than my friend and tune it what a mess !

 

Have to change the relucter wheel count in the ecm i knows that do this all the time