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Anyone regret doing a Cummins swap?

YotaAtieToo

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Everyone always says that a Cummins swapped ford would be the ultimate truck. Yet everyone I know who has had one, ends up getting rid of it.

I've had my 97 7.3/zf5 CCLB F350 for almost 10 years. It's been a great truck, I've done some upgrades and mods, but always tried to keep it fairly stock for reliability reasons, which has worked out so far. It's got 340k miles and is looking like it might have blown head gaskets or some other internal damage causing oil in the coolant and coolant smoke out the exhaust. I can't see pulling the heads and just doing gaskets considering the mileage. I also am at the point where I was just about to do some upgrades and maintenance to the engine, injectors, turbo, up pipes ect. So long story short, I'm looking at a lot of money to keep the 7.3 going.

So obviously a Cummins swap has to be considered. The problem with that route is that prices on donors have gone bonkers. I don't really like the idea of paying $2500+ for an engine that may need shit replaced also. I do happen to know a buddy who picked up an FL70 to move for cheap($2500). He doesn't plan to keep it, and I may be able to get it off of him for cheap or get a similar truck from the same place. His has a 24v Cummins with some type of allison with an OD behind it. It's tempting to just slap both of those into my truck and run a divorced 205. But I also like the idea of just leavingy current drivetrain alone and just buying the adapter.

I've read a little about the swap, seems that it's been done so many times, everything is pretty well figured out. Different exhaust manifold to move turbo forward, gas truck cruise servo, little adapters here and there, ect.

I'm sure my most realistic option is to try and find a good used donor, but I'd still have to do all the shit I wanted to do to mine and there is always a risk I'm buying another one with issues.
 
Watch a few episodes of zip ties and bias plys on youtube. That guy thinks a cummins ford is the end all be all. I think they are over weight and under powered. You could probably huck a few HGs at it in a day and just keep flogging it.
 
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Lol this coming from a guy with the handle "rockyota83" :stirthepot: I've always stayed clear of Fords and I'm not a diesel fan. So I can't elaborate on your claims :grinpimp:
 
I had a 99 dodge 2500, 24 valve and my 1995 F350 PSD at the same time.

Bone stock the cummins had nothing on the PSD, the PSD was more fun to drive as a daily driver. More quiet, more get up and go.

Towing really the PSD towed better. The cummins was okay, it found a groove and would pull just fine.
I could pull the same load with my PSD at 75 and the cummins would hold about 68. But that may have to do with gearing or something else.

It isn't until you start wanting to build big HP and TQ that the cummins really shines. It is stupid cheap and easy on a cummins and all while still being dependable.

My 95 PSD has intercooler, upgraded turbo and injectors now, I put out around 390 hp and 700 ft. lbs. It is more than enough for me and what I do. Plus I no longer feel like I need to race people or be the first to the top of the hill pulling stuff.

My old dodge is still running around, body is pretty much gone. But you can hear from 3 blocks away that the engine still sounds healthy.
It had about 240k on it when I got rid of it and it was showing signs of needing a headgasket.

Not sure how that compares to the 12 valve cummins, but I certainly saw nothing that made me feel the conversion was worth it.
 
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Watch a few episodes of zip ties and bias plys on youtube. That guy thinks a cummins ford is the end all be all. I think they are over weight and under powered. You could probably huck a few HGs at it in a day and just keep flogging it.

Im not saying it’s the best thing to do, but underpowered? Have you not seen the drag races where a Cummins beats a Vette?
 
Head gaskets and cups wouldn't be too much of a job compared to engine swap.

Go S3XX/T4 turbo kit with some smallish new injectors (AC codes, or stage 1).
Aluminum super-duty intakes and e-fuel would round out the package.
If you need to go in the bottom end then all bets are off on cost, might be better to find a core to refresh.

Do the math on the turbo/injectors to see how you are looking, I figure easy $6k to do all that.
 
I went from a V10 to the 12v in my Excursion (and I ran the dodge donor prior to that for years before buying the Ex). I eventually got tired of how loud it was and sold it earlier this year. Really that was my only complaint other than the clutch pedal effort.

Stock it was a turd though. Injectors, turbo off a newer truck, and some supporting mods woke it up decently. Towed about the same as my dads lightly tuned 7.3 truck.
 
Irate s364.5 t4 kit ceramic coated with .91 exhaust housing and intercooler kit, pretty complete kit.
$3,639.29

New AC (high torque T444E) code injectors $2500

Full e-fuel kit with bowl delete and regulated return $1000

Plus head gaskets, valve cover gaskets, cups, head bolts or studs, gonna add another $1k easy I bet.
Fancy e-fuel kit is a luxury but would be really nice to have vs stock or even home brew.

This would get you a 400 hp truck with excellent drivability, MUCH improved drivability over the stock setup.
 
Irate s364.5 t4 kit ceramic coated with .91 exhaust housing and intercooler kit, pretty complete kit.
$3,639.29

New AC (high torque T444E) code injectors $2500

Full e-fuel kit with bowl delete and regulated return $1000

Plus head gaskets, valve cover gaskets, cups, head bolts or studs, gonna add another $1k easy I bet.
Fancy e-fuel kit is a luxury but would be really nice to have vs stock or even home brew.

This would get you a 400 hp truck with excellent drivability, MUCH improved drivability over the stock setup.
That seems like a lot of turbo for those injectors. But then I am not a perfomance expert.

I am running 180/0 injectors, with stage 1 KC turbo with .84 housing. On stock HPOP and Stock fuel. There are less oil hungry injectors than mine.

Every truck is different. Everyone told me I couldn't do it, but it is working. Custom tuning is very important in getting the most out of your setup.

So my opion is you don't need to dump everything, make a couple of upgrades at a time so how the truck responds. Watching things like fuel pressure or HPOP before you go throwing new ones in there. Seems like the aftermarket stuff is not always the best quality either.
 
I just lost a power steering pump gear (gear shed its teeth in the front cover...30mph, straight road, nothing special...quickdrawbrand.com). Not to mention Ive had countless issues from the get go with oil pressure (pinhole in pan pickup) and black beauty blasting media in the injector lines (WTF) causing COUNTLESS startup/running issues).

I love the truck (1974 crewcab, '96 ppump, ZF6, superduty axles, coilovers, custom radius arms etc etc)....but Im ready to have the problems done with. Fuck.
 
That seems like a lot of turbo for those injectors. But then I am not a perfomance expert.

I am running 180/0 injectors, with stage 1 KC turbo with .84 housing. On stock HPOP and Stock fuel. There are less oil hungry injectors than mine.

Every truck is different. Everyone told me I couldn't do it, but it is working. Custom tuning is very important in getting the most out of your setup.

So my opion is you don't need to dump everything, make a couple of upgrades at a time so how the truck responds. Watching things like fuel pressure or HPOP before you go throwing new ones in there. Seems like the aftermarket stuff is not always the best quality either.
That 364.5 is on the small end of the s3xx line up, I think there might be one smaller but I wouldn't buy one on my suggestion, I'd talk to the vendor extensively about the goal.

I agree totally with your statement on one thing at time but that's also how you end up working on the truck as much as driving it.

I am getting more inclined to buy ALL the parts (even at a large total) and work until it's done Instead of work some every weekend.
 
So, I'm the odd guy here..

Old Ford mechanic, but do not own a older Ford diesel.

1. Find a bag of money. Buy a new Duramax/Ford. Profit
2. Find a smaller bag, buy a 2 or 3 year old Duramax/ford. Profit
3. Buy cheaper beer, buy afore mentioned parts, get another 300k out of the 7.3. Win


( notice no mention of swapping the Cummins into a non dedicated hot shot truck.. )
 
It'd be cheaper and easier to just make your PSD reliable while turning it up at the same time.

Thats what I've been saying since I bought it. Now assuming mine is fucked up I'm not so sure. All the parts I want to throw at it (injectors, up pipes, turbo and exhaust brake) I'm looking at $4k. Plus finding a good donor engine, or rebuilding mine will be a few grand.

Also assuming I can get that 24v and Allison from the FL70, then a few grand to properly put it in there. Or same thing if I keep my zf5. Its looking like it might actually be cheaper to do the swap. As far as upgrades on the Cummins, I'd be happy with a tuner and 04-07 turbo for ~$400.

I had a 99 dodge 2500, 24 valve and my 1995 F350 PSD at the same time.

Bone stock the cummins had nothing on the PSD, the PSD was more fun to drive as a daily driver. More quiet, more get up and go.

Towing really the PSD towed better. The cummins was okay, it found a groove and would pull just fine.
I could pull the same load with my PSD at 75 and the cummins would hold about 68. But that may have to do with gearing or something else.

It isn't until you start wanting to build big HP and TQ that the cummins really shines. It is stupid cheap and easy on a cummins and all while still being dependable.

My 95 PSD has intercooler, upgraded turbo and injectors now, I put out around 390 hp and 700 ft. lbs. It is more than enough for me and what I do. Plus I no longer feel like I need to race people or be the first to the top of the hill pulling stuff.

My old dodge is still running around, body is pretty much gone. But you can hear from 3 blocks away that the engine still sounds healthy.
It had about 240k on it when I got rid of it and it was showing signs of needing a headgasket.

Not sure how that compares to the 12 valve cummins, but I certainly saw nothing that made me feel the conversion was worth it.

I'm pretty familiar with the 24v power, same buddy with the FL70 had a 99/5spd for years and I rode 1000s of miles in it.

Bone stock, a 12v/24v or 7.3 is a turd. My 7.3 can only gain ~50hp without doing injectors. Just a tune really wakes the Cummins up. I had my 97 and a 90 dodge 12v at the same time. With a few hundred in upgrades to that 12v, it was a rocket. Then I added a he351cw off an 05 common rail and it was damn impressive for stock injectors. So much easier to work on as well.

I wouldnt pull a good running 7.3 out to swap, but a blown one that needs about everything external replaced as well kinda changes it.
 
Thats what I've been saying since I bought it. Now assuming mine is fucked up I'm not so sure. All the parts I want to throw at it (injectors, up pipes, turbo and exhaust brake) I'm looking at $4k. Plus finding a good donor engine, or rebuilding mine will be a few grand.

Also assuming I can get that 24v and Allison from the FL70, then a few grand to properly put it in there. Or same thing if I keep my zf5. Its looking like it might actually be cheaper to do the swap. As far as upgrades on the Cummins, I'd be happy with a tuner and 04-07 turbo for ~$400.



I'm pretty familiar with the 24v power, same buddy with the FL70 had a 99/5spd for years and I rode 1000s of miles in it.

Bone stock, a 12v/24v or 7.3 is a turd. My 7.3 can only gain ~50hp without doing injectors. Just a tune really wakes the Cummins up. I had my 97 and a 90 dodge 12v at the same time. With a few hundred in upgrades to that 12v, it was a rocket. Then I added a he351cw off an 05 common rail and it was damn impressive for stock injectors. So much easier to work on as well.

I wouldnt pull a good running 7.3 out to swap, but a blown one that needs about everything external replaced as well kinda changes it.
This type of thinking is how I ended up with brand new F350 and a $935 month payment :lmao:
 
I love the 12 valve in my 68 and would probably do it again, although it would cost 3x as much today vs 10 years ago. I don't tow heavy and it isn't turned up much. Not to brag, but it did run a few 17.90s in the quarter in Indy last summer.

Cummins swapped newer Fords make sense when you can get a cheap 6.0/6.4 that's blown up with a mint body and interior to toss a Cummins in. I wouldn't swap a 7.3 PS for a Cummins.

Your stock motor made it 340k. I say do the head gaskets, maybe some other preventative maintenance/performance parts and keep on keepin' on.
 
first engine made it over 340k with few (??) complaints.

refresh and be good for another 340k?

"refresh" is going to be $6-10k, which is easily enough to do a swap and the point of this thread.

Head gaskets and cups wouldn't be too much of a job compared to engine swap.

Go S3XX/T4 turbo kit with some smallish new injectors (AC codes, or stage 1).
Aluminum super-duty intakes and e-fuel would round out the package.
If you need to go in the bottom end then all bets are off on cost, might be better to find a core to refresh.

Do the math on the turbo/injectors to see how you are looking, I figure easy $6k to do all that.

Assuming head gaskets is all it is. I've ran the thing pretty hard since I got it at 200k. From what I've read, just blowing head gaskets is pretty rare.

I've read circles in 7.3 up grades, so I kinda know what I'm getting into there, at least cost wise. All the stuff I wanted was about $4k. But that's also leaving the fuel system and hpop alone.

I went from a V10 to the 12v in my Excursion (and I ran the dodge donor prior to that for years before buying the Ex). I eventually got tired of how loud it was and sold it earlier this year. Really that was my only complaint other than the clutch pedal effort.

Stock it was a turd though. Injectors, turbo off a newer truck, and some supporting mods woke it up decently. Towed about the same as my dads lightly tuned 7.3 truck.

I'd honestly be surprised if the in cab noise was louder than the 7.3. Part of my plan with the truck either way is scrap the carpet, add sound insulation and new vinal floors.

I'm sure your dad's was a super duty 7.3? The obs needs turbo and injectors to even be close to a tuned Cummins imo.

Id rather have less but reliable power, than a bunch of bastard parts in a swap that I have to remember what they are.

I don't need a bunch of power, just more usable power. As it is, I have to wind the shit out of it to pull wieght up a decent grade. Tired small injectors and a laggy turbo are to blame. The upgrades I'd do to the 7.3 would be very mild. If I did the Cummins if would just be a little more fuel and a better turbo.

I am trying to avoid the bastard parts. From what I've read, they have it down. If I keep my trans, I'll be using a 6.0 ford starter. The rest will either be stock Ford or stock Cummins. I can make a little list or binder to keep in the glove box for the handful of parts that aren't for either one.

Using the allison and a divorced 205, kinda simplifies it in a way, but also could make it a little odd since I now have an mdt trans and a tcase from a 70s truck. I'm pretty hesitant to use that trans.
 
Before I do anything, I guess I should diagnose it. I'm not an engine guy at all, but when I first started having problems, I found a guy about an hour away who people recommended for 7.3 work. I'd imagine he has a bore scope and compression tester adapters for this thing.
 
Before I do anything, I guess I should diagnose it. I'm not an engine guy at all, but when I first started having problems, I found a guy about an hour away who people recommended for 7.3 work. I'd imagine he has a bore scope and compression tester adapters for this thing.
Head gaskets are rare.

My bet would be oil cooler, pretty common failure of high miles engines.
All you need is a cooling system tester, pretty cheap at HF.

But you could make one real easy with a pressure regulator, gauge and ball valve with shop air.
 
Head gaskets are rare.

My bet would be oil cooler, pretty common failure of high miles engines.
All you need is a cooling system tester, pretty cheap at HF.

But you could make one real easy with a pressure regulator, gauge and ball valve with shop air.

Guess you forgot the other thread. I just did a new oil cooler.

Bad Oil cooler also won't put coolant in the exhaust.

What's the coolant system tester do? Just pressurize the coolant system?
 
I did a quick look on CL and of course found a few of the "good running engine, only eleventy hundred million miles, $2500 firm" with a Pic of it on its side in the back of a truck covered in snow. :homer:

But I also found a few with reasonable miles, still in a truck for ~2k. I won't buy one with out hearing it run.
 
Everyone always says that a Cummins swapped ford would be the ultimate truck. Yet everyone I know who has had one, ends up getting rid of it.

I've had my 97 7.3/zf5 CCLB F350 for almost 10 years. It's been a great truck, I've done some upgrades and mods, but always tried to keep it fairly stock for reliability reasons, which has worked out so far. It's got 340k miles and is looking like it might have blown head gaskets or some other internal damage causing oil in the coolant and coolant smoke out the exhaust. I can't see pulling the heads and just doing gaskets considering the mileage. I also am at the point where I was just about to do some upgrades and maintenance to the engine, injectors, turbo, up pipes ect. So long story short, I'm looking at a lot of money to keep the 7.3 going.

So obviously a Cummins swap has to be considered. The problem with that route is that prices on donors have gone bonkers. I don't really like the idea of paying $2500+ for an engine that may need shit replaced also. I do happen to know a buddy who picked up an FL70 to move for cheap($2500). He doesn't plan to keep it, and I may be able to get it off of him for cheap or get a similar truck from the same place. His has a 24v Cummins with some type of allison with an OD behind it. It's tempting to just slap both of those into my truck and run a divorced 205. But I also like the idea of just leavingy current drivetrain alone and just buying the adapter.

I've read a little about the swap, seems that it's been done so many times, everything is pretty well figured out. Different exhaust manifold to move turbo forward, gas truck cruise servo, little adapters here and there, ect.

I'm sure my most realistic option is to try and find a good used donor, but I'd still have to do all the shit I wanted to do to mine and there is always a risk I'm buying another one with issues.

Although Grendel put one in a pre-smog Chevy; he'd be a good candidate for an informed opinion.:beer:
 
I never regretted either one of mine, 75 high boy, pulled the 360/c6 for a low mile cummins recon 1st gen intercooled and a 618a, swapped 410s to 355s and got 17.5 hwy on 35s, romping on it and having a blast. Never towed, just a cowboy Cadillac

Several years later I bought a 95 ppump 5 speed 4wd rollover at auction, then found a really really clean 88 cclb 4wd f350 that blown up the idi, and it was a 5 speed truck

Hard to find parts? It's been 12 years since I built it, no sweat.

Damn near made for it, 6.0 ford intercooler, 93 dodge radiator and lower hose, power steering hose from a 1988 e150 5.8, the ford and dodge hydro clutch lines had the same fitting. I took the ford battery cables and flipped them for the driver side starter. An alternator shop sells the external voltage regulator for $25.

I loved that truck, on 37s with 410s it could have had another overdrive pulling 8k.

Only weighed 6400lbs, they are significantly lighter than a 2nd gen dodge

Only sold it because I had some deferred maintenance backing up, divorced with 3 small kids, and bought a low mile ccsb duramax Allison to flip, and really took a liking to hydroboost, 4 wheel disc, not shifting, and being able to flip a u turn with kids fighting over barbies in the back seat....i needed that minivan with tow capacity

I'm gathering the parts to do it again, this time with a zf6, and super duty axles



But if you're gonna run a 24v and an Alison from a mdt? Fuck that, just put another 7.3 in it. Get 2big to help you find a good running f450 from CA that can't pass smog and rock out
 
Guess you forgot the other thread. I just did a new oil cooler.

Bad Oil cooler also won't put coolant in the exhaust.

What's the coolant system tester do? Just pressurize the coolant system?
Lol yeah thats probably why i usually try to avoid armchair troubleshooting.

Drop the oil and leave the drain plug out? Again doesn't tell you much but it does tell you what you already know, water is not where it's supposed to be.
The more through version is to pull the pan and verfiy water is not coming through cylinder walls because the SCA wasn't maintained and the cylinders are pin holed.
 
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