Rawze.com: Rawze's ISX Technical Discussion and more
cm2250 swap to cm2350 - Printable Version

+- Rawze.com: Rawze's ISX Technical Discussion and more (http://rawze.com/forums)
+-- Forum: Big Truck Technical Discussion... (/forumdisplay.php?fid=1)
+--- Forum: Ask Your question... (/forumdisplay.php?fid=45)
+--- Thread: cm2250 swap to cm2350 (/showthread.php?tid=6069)

Pages: 1 2


RE: cm2250 swap to cm2350 - Breeze - 04-15-2020

(04-15-2020 )SquareOne Wrote:  
(04-14-2020 )Breeze Wrote:  ... any input on this would be appreciated for sure , don't wanna have a truck , with newer engine that wont run ...


Rawze / Unilevers is correct on the custom tuning to make the swap work as it should. Yes, you can swap the 2350 into the 2250 slot, but I believe the ECM on the 2250 has 2 wiring harnesses coming from the truck whereas the 2350 has 3....so the ECM from the 2250 would have to run the 2350 engine. This is exactly how my situation ended up as Rawze referenced.


The engine will run and probably haul freight (although I don't know how long). Once Rawze explained the differences to me, I was skeptical about driving it to the compound much less putting any weight behind it. There are many significant differences that will effect reliability, MPG, efficiency, engine life, etc....

However, with the proper tuning as suggested, it will work very well. After over 100k on mine, it's been great. MPG has averaged just over 8.5 over the last 100k (although I can't seem to get it back to what it was last summer---hopefully that's just the weather all over the place down here).

I would imagine if one could get a stellar deal on the engine and did the proper procedure to ensure long service life, you could come out way ahead. Of coarse, I'd have to compare an inframe cost to the replacement cost to be sure you'll be ahead financially with minimal headache.

yes i was planning on using the complete harness and the demandated ecm from my 2250 transfered over to the 2350


RE: cm2250 swap to cm2350 - Breeze - 04-15-2020

(04-15-2020 )Unilevers Wrote:  did i read that wrong? i was under the assumption he was swapping the entire 2350 engine into his truck that used to have a 2250 in it? If your trying to mix match a 2250 and turn it into a 2350 that doesn't work well without heavy custom tuning and im not sure why anyone would do that.

nope you read it correctly, the swap was using a very low mileage cm2350 , and transferring the harness and ecm [custom tuned ] to the 2350


RE: cm2250 swap to cm2350 - Breeze - 04-15-2020

yep thanks for all of your input guys and yes an inframe would be easier in the long run , but mostly its a time issue , im out 30 days everywhere , even mr h , I missed my chance , and what I was speaking of was using a newer cm2350 , but transferring my original cm2250 harness and de mandated ecm over to the new engine , sorry for the confusion


RE: cm2250 swap to cm2350 - SquareOne - 04-15-2020

(04-15-2020 )Breeze Wrote:  .... what I was speaking of was using a newer cm2350 , but transferring my original cm2250 harness and de mandated ecm over to the new engine , sorry for the confusion...

^^ This will def require custom tuning in order to run properly/reliably. Similar to my situation.

-- If you were to use the complete harness, ecm, and other necessary components from the donor truck, then essentially you would have a capable, now 'cm2350', truck which should run like the donor previously ran. At least that's what I'd assume.


RE: cm2250 swap to cm2350 - Unilevers - 04-15-2020

(04-15-2020 )SquareOne Wrote:  
(04-15-2020 )Breeze Wrote:  .... what I was speaking of was using a newer cm2350 , but transferring my original cm2250 harness and de mandated ecm over to the new engine , sorry for the confusion...

^^ This will def require custom tuning in order to run properly/reliably. Similar to my situation.

-- If you were to use the complete harness, ecm, and other necessary components from the donor truck, then essentially you would have a capable, now 'cm2350', truck which should run like the donor previously ran. At least that's what I'd assume.

you are correct on both accounts


RE: cm2250 swap to cm2350 - Signature620 - 04-15-2020

Would it not be easier to use the 2350 ECM and have the OEM harness repinned? Seems like less messing around to me. Any auto electrician worth knowing would be able to tackle it in no time.


RE: cm2250 swap to cm2350 - JimT - 04-15-2020

Not sure about other ppl's 2250's, but my cm2250 has 3 harnesses to the ECM. 2 from cummins and 1 oem.

On the bright side, all the wiring schematics are available from the different harnesses so I'd say use the harness for the 2350 and only adjust the OEM harness if any pins are different. As cummins determines the pinout for all the harness connectors it shouldn't be too hard.