Cat to Cummins swap - Need info help!

jt1980a

Active Expediter
Ok, I have a cat c-7 (05' 330hp with 114,000 miles). This thing is the second cat I have owned and just as big of a pile as the first. No power compared to the cummins 8.3L. I get 12-16 mpg with my 8.3's and this cat only makes 7.1 mpg. And if you are wondering they all have the same chassis specs (rears @ 3.9 with 13spd overdrives). I HAVE to replace my 05' cat with a cummins 8.3, ISC, or PX8 in my 05' freightliner m2, before I start it on fire and push it over a cliff! Does anyone have any info on this swap. Will the cab electronics work with the cummins with minor mods? Will I have to change radiator or Air charge cooler? How much is involved outside of installing the motor in the truck? Please help before it becomes an insurance claim!
Thanks,
Justin
 

zorry

Veteran Expediter
A) It'd be simpler to sell it and buy a different truck.
B) there's an outfit on the west coast,southern Oregon I believe,that does engine swaps. They may sell you wiring harnesses and such. They build the harnesses for about $2500 each.
I Believe they are affiliated with a Ford or Sterling Dealership.
Coos Bay Oregon ? They advertise in The Truck Paper.
 

jt1980a

Active Expediter
thank you for the info on the harness.

This is kind of a specialty truck and buying a different truck isnt a financially fesible option.
 

zorry

Veteran Expediter
If you don't have a replacement contact them and see what they advise. Let us know,Thanks
 

jt1980a

Active Expediter
If you don't have a replacement contact them and see what they advise. Let us know,Thanks

Can't find a wiring harness to make everything work as it should. So......I ended up throwing injectors and heui pump on the yellow boat anchor. Still a gutless wonder! The only thing that amazes me about CAT is the poor fuel mileage with its under powered design and the astronomical cost of its poorly designed and cheaply built parts. Ok, so there is more than one thing that amzes me about CAT. I am truly astonished that the department of transportment hasnt put an end to CAT. I mean come on, its a liability to other motorist. These things cant even get out of their own way going downhill with a tailwind. And whats up with the clatterpillar stench? Who did they have to suck @ the E.P.A. to certify this modern marvel of eye watering, throat burning and nose hair curling mass of pure engineering failure!!! Ok, maybe I'm being a little to harsh on you cat guys? I will give this engine (if you can call it that) a little credit. Those of you who change your own oil know what im talking about when i say that the oil pan on these things are so thin they solidify the concept POP cans can hold 7 gallons without utilizing a thicker more durable container. Point is when they rust threw in a few years you don't have to worry about grass growing under your truck. But why why put a cummins quality oil pan on when the factory set of tires outlast the engine???

This winter i will transplant an cummins in this truck and figure out the wiring, gauges, etc. Hopefully the truck won't go into shock? It's kind of like taking a riddalin induced 18 yr. Old off the medication and handing him a box of pixie stixs, 12 pack of budweiser, handful of condoms, dozen viagra and dropping him off at girls serority house on a Saturday night.
 

Dynamite 1

Moderator
Staff member
Fleet Owner
Guess it depends on the situation, I know some who have had good luck with the c7 and other in your predicament. If it was me, come winter I would put a c9 in it. Swap should be easier plus the c9 has been a very good and durable motor for all the people I know running them. They have good power and you can get 9 mpg out of them. I know of 2 with over a million on them and 4 others aproaching 900,000 with the only problem being a set of injectors. Just one set though. I'm not a big cat fan but this is the only one I would have other than an old c10.
 
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jt1980a

Active Expediter
Good to know. But there is only two thibgs that scare me. First is spiders and second is yellow paint on a motor. C9 may be better than a c7 but right now I have 3000 miles on new inj. Pump and injectors and they are out again. Pulled tge fuel filter and looks like someone dumped a tablespoon of silver filings in the filter. Right now im considering a briggs & stratton motor from the lawnmower. I'm confident it will have more power, get better mileage, abd be way more reliable!
 

jt1980a

Active Expediter
What a waste of $110k. Tomorrow I will burn it to an unrecognizable melted gob of goo. Gonna just bite the bullet and order a new one. Im not going to let CAT make a dollar off parts from the next owner or should I say uneducated sucker. 3rd and last cat in my lifetime! I'll quite trucking if it comes down to Kitty Crap motors!

Sorry guys, I'm just all torqued up over this "fudged over rebuilt 3 times and de-designed afterward powerstroke motor". And no I do not think highly of anything related to Ford.
 

zorry

Veteran Expediter
The people that may build you a harness:
Kustom Products,Coos Bay,Or
541-267-6990 or 888-564-8890

If it's possible I believe they can do the swap,complete,in their shop.
 
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jt1980a

Active Expediter
Thanks zorry,
Already checked with them but not possible on myy truck without modifications to body/hood. The freightliner m2 up to 07' didnt have the clerance. Built to accomadate cat (notice all lower case letters :) only and cummins is taller. I know it can be modified but where does a guy stop throwing money @ something? I pulled my new tranny and out old scab tires back on. Drinking a beer and trying to talk myself into lighting it as I'm typing. Did pick up a build order form this morning from my freightliner dealer.
 

Turtle

Administrator
Staff member
Retired Expediter
You realize that, at this point, if your truck were to catch on fire, through no fault of your own, if it were struck by lightning, you're screwed.
 

jt1980a

Active Expediter
at this point I dont care anymore. I'd just eat the $$ for the satisfaction of knowing that CAT wouldnt make a Cent on parts from this engine ever again! Can you believe they wont even get back to me? As you can tell Im a humble person, only wanted to make a few points.
 

guido4475

Not a Member
What a waste of $110k. Tomorrow I will burn it to an unrecognizable melted gob of goo. Gonna just bite the bullet and order a new one. Im not going to let CAT make a dollar off parts from the next owner or should I say uneducated sucker. 3rd and last cat in my lifetime! I'll quite trucking if it comes down to Kitty Crap motors!

Sorry guys, I'm just all torqued up over this "fudged over rebuilt 3 times and de-designed afterward powerstroke motor". And no I do not think highly of anything related to Ford.

Ford has absolutely nothing to do with Cat.The problem is, you should of researched that engine before buying the truck.You're expecting a boy to do a man's job.It is a dry sleeve engine.They have a history of problems, such as what you have experienced, along with the valves tightening up over time, making the valve slap the head, and BOOM! The head of the valve snaps off. They need valve adjustments on a regular basis to prevent this, by someone who knows what they are doing.Some have had good luck with it,others have not.I had one, and had reasonably good luck with it, even though it needed alot of preventative maintenance to be dependable.Will I buy a truck with a 3126/C-7 again? NO. I prefer Cummins, myself.Sorry for sounding so harsh here, but the only one to blame for what you are going through is you yourself.Research a little deeper next time.This subject has been on here several times in the past years.
 

jt1980a

Active Expediter
Guido,
I cant agree with you more, it is my fault I did not research enough into the mechanics of this motor. Now, to claim I have no one to blame but myself would be a stretch. Afterall, I didnt design or market the C7. Nor do the truck manufacturers utalize my imput on which engines they will use in their lineup, and in the case of the m2 106 its either a CAT or a Mercades. Prior to my experiences I felt confident the the CAT was a healthier choice. Man was I wrong! As far as dry sleeve vs wet sleeve, I was aware of this and the dry sleeve design doesnt worry me much as my preventative maintenance is second to none and I very rarly have a problem with internal components. Now, Ford and Cat are two seperate companies both building diesel engines right? Wrong! It would be more correct to compare Navistar to CAT as Ford branded diesel engines are actually navistar engines. Since navistar and CAT are to say "in bed with one another" in both the design AND production of engines and parts for the C7 truck version engine era, I would have to disagree with your opinion that ford and Cat dont have nothing to do with one another (when it comes to engines anyway). Acutally, if you were to go to your local cat dealer today and ask him to order you a set of C7/C9 injectors in. You would find that they are stamped Navistar NOT cat. If you were to order a set of injectors in for your, say ford 6.0L, you would most likely find them stamped Navistar as well.
I am not trying to be harsh either, but these are the simple truths that I always seem to find out the hard way lol. Yes, I also bought my first Ford this year :(
 

dieselmech

Active Expediter
Guido,
I cant agree with you more, it is my fault I did not research enough into the mechanics of this motor. Now, to claim I have no one to blame but myself would be a stretch. Afterall, I didnt design or market the C7. Nor do the truck manufacturers utalize my imput on which engines they will use in their lineup, and in the case of the m2 106 its either a CAT or a Mercades. Prior to my experiences I felt confident the the CAT was a healthier choice. Man was I wrong! As far as dry sleeve vs wet sleeve, I was aware of this and the dry sleeve design doesnt worry me much as my preventative maintenance is second to none and I very rarly have a problem with internal components. Now, Ford and Cat are two seperate companies both building diesel engines right? Wrong! It would be more correct to compare Navistar to CAT as Ford branded diesel engines are actually navistar engines. Since navistar and CAT are to say "in bed with one another" in both the design AND production of engines and parts for the C7 truck version engine era, I would have to disagree with your opinion that ford and Cat dont have nothing to do with one another (when it comes to engines anyway). Acutally, if you were to go to your local cat dealer today and ask him to order you a set of C7/C9 injectors in. You would find that they are stamped Navistar NOT cat. If you were to order a set of injectors in for your, say ford 6.0L, you would most likely find them stamped Navistar as well.
I am not trying to be harsh either, but these are the simple truths that I always seem to find out the hard way lol. Yes, I also bought my first Ford this year :(

I hate to say but your completely wrong. No CAT injector made will list Navistar on it. I just walked out and checked personally to be 100%, even made sure it came from a c7. KAL prefix to be exact. Ford and Navistar are both also completely seperate entities so your "natistar ford cat" triangle falls apart there. Now Navistar and CAT did share some on the injection system (HEUI), namely that CAT has shared their technology with Navistar, but their engine association ends there in regards to the on highway engines up to their withdrawl from the on highway market. I can understand your frustration and cannot speak for why they only covered 45% of the repair (percentage repairs are actually fairly common depending on circumstances) but that doesnt mean you can go running around shouting false information as if it were fact.

Also all the ford pickup diesels are actually Navistar outside of a different calibration and the occasional change in electronics to accomodate a pickup application, think more like putting a cummins in a kenworth rather than ford having a real say in the engine design.
 

mike6784

Active Expediter
Hmmm cat has nothing to do with ford and like said before a cat will run a long time if taken care of. Cats do melt o rings on the sleeves on 5/6 cylinders due to an idiot who bogs the truck up a hill or running heavy everytime. And they must have and overhead ran on them more often than others . Huh and a cummins???? I don't get where you think they will last any longer they run hot also and have cam problems . If your wanting a engine you can run in the dirt buy a detroit!
 

jt1980a

Active Expediter
I hate to say but your completely wrong. No CAT injector made will list Navistar on it. I just walked out and checked personally to be 100%, even made sure it came from a c7. KAL prefix to be exact. Ford and Navistar are both also completely seperate entities so your "natistar ford cat" triangle falls apart there. Now Navistar and CAT did share some on the injection system (HEUI), namely that CAT has shared their technology with Navistar, but their engine association ends there in regards to the on highway engines up to their withdrawl from the on highway market. I can understand your frustration and cannot speak for why they only covered 45% of the repair (percentage repairs are actually fairly common depending on circumstances) but that doesnt mean you can go running around shouting false information as if it were fact.

Also all the ford pickup diesels are actually Navistar outside of a different calibration and the occasional change in electronics to accomodate a pickup application, think more like putting a cummins in a kenworth rather than ford having a real say in the engine design.

Mine were stamped Navistar, when you get your next shippment of yellow chineese junk look again! I am aware that navistar made diesel engines for ford and ford really did not design it but I just wanted to throw it in there since I was having bad experiences with ford as well. As far as cummins goes I right now my truck that has the most miles on it has an 8.3 cummins with over 1.3 million local miles and over 80,000 hours and had a cracked head at 700,000 miles that I replaced. Pullt the pan and checked the runout and plastic-guaged the original bearings just to check. They were all on the tight end of factory specs! Rings and sleves were good as well with minimal ridge (only from a little carbon build up). Good cross action on the cylinder walls and it still has 65 psi oil pressure running down the road at 1500 rpm, just like when I bought it with 100,000 miles. And, I have more 8.3 liters with another nearing 1,000,000 miles with only a head gasket. I'm guessing you work at a cat dealership or specialize in cat? Nothing against you, I mean no disrepect, you chose a good profession if you fix cat. You have awesome job security.

Ps. My engine is KAL family as well
 

crazodiejaody

New Recruit
I know this is an old post but here goes , first cat engineered and designed the Huey system .
second did anyone come up with the info for the swap . I'm doing one on a 04 Freightliner cat 7.2 to cummins 8.3 could use some help with the harrness. any help is appreciated.
 
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