7.3L Powerstroke or 5.9L Cummins with over 200k miles -- still lots of life, or not?

[Builder]

Are you talking intake manifold, or air-filter housing, and tubes that feed air to the turbo?
QUOTE]

Specifically, the air filter and the tube that connects the air filter to the turbo. The stock Ford airbox leaked and there was a silent recall on them. For a diesel, I would not advise using foam filters; too much maintenance keeping 'em clean and oiled, plus too many horror stories of dirt getting past them and ruining turbos. A good pleated paper filter works great. The Tymar is a tube made for the 7.3 and uses a huge Donaldson 6637 pleated paper element.

The 7.3's connect from the exhaust manifold to the turbo inlet collector with a set of up-pipes. There are some high-dollar upgrades available there too...as well as bigger intake manifolds. For most of us, the cost/benefit ratio rules out goodies like that. And of course, there are goodies like upgraded turbos...and head studs...and pistons...the sky is the limit.

I've heard of 7.3's yielding over 800 hp on the dyno. There's even a common rail conversion being developed by at least one vendor. I'd say within a year or so we'll see the 7.3 break the magical 1000 hp mark. (My personal target is 400 hp, I'm only $900 short right now...)

For us mere mortals, I'd recommend the air intake, downpipe, and chip. For any diesel, I'd strongly recommend a EGT (pyro) gauge, mounted pre-turbo. A boost gauge is nice (measures the turbo's performance) but isn't critical IMHO.

The problem is that once you get past the 600HP mark, the 7.3 is likely to scatter. It won't hold up to extremes like a 5.9L, a Duramax, a 6.4L or even a 6 leaker.
The problem is it isn't "hard" enough. it has a weaker bedplate than newer diesels.
Buddy of mine built 3 or 4 of them and learned the expensive way that they just can't hold the power once it gets that high without serious expense. I would think you'd need to start thinking about a girdle or some other kinds of structural upgrades.

 

[WH401]

Are you talking intake manifold, or air-filter housing, and tubes that feed air to the turbo?
QUOTE]

Specifically, the air filter and the tube that connects the air filter to the turbo. The stock Ford airbox leaked and there was a silent recall on them. For a diesel, I would not advise using foam filters; too much maintenance keeping 'em clean and oiled, plus too many horror stories of dirt getting past them and ruining turbos. A good pleated paper filter works great. The Tymar is a tube made for the 7.3 and uses a huge Donaldson 6637 pleated paper element.

The 7.3's connect from the exhaust manifold to the turbo inlet collector with a set of up-pipes. There are some high-dollar upgrades available there too...as well as bigger intake manifolds. For most of us, the cost/benefit ratio rules out goodies like that. And of course, there are goodies like upgraded turbos...and head studs...and pistons...the sky is the limit.

I've heard of 7.3's yielding over 800 hp on the dyno. There's even a common rail conversion being developed by at least one vendor. I'd say within a year or so we'll see the 7.3 break the magical 1000 hp mark. (My personal target is 400 hp, I'm only $900 short right now...)

For us mere mortals, I'd recommend the air intake, downpipe, and chip. For any diesel, I'd strongly recommend a EGT (pyro) gauge, mounted pre-turbo. A boost gauge is nice (measures the turbo's performance) but isn't critical IMHO.

I highly doubt you'll see a 1000 hp 7.3, their specs have a hard time handling even the load that 500 hp puts on their internals. Then when you add in the fact that because of the popularity of the 6.0, because of it's better performance even with as bad of an engine as it is, and the fact that the 7.3's popularity with hot rodders continues to diminish, the ability to find any kind of real good high performance parts for it is very small. The 7.3 is a good engine in stock form, but when you start modding it you quickly run into the limit of it's design. You also have to look at the previous DieselPower Challenges from the last 4 years. While yes, 7.3 do enter, there never able to hang with the newer 6.0's, D-max's, or 5.9's.

 

[Bill_C]

Try 823 hp on spray, you really need to get out more.

638 fuel 823 on N20 - Powerstroke Nation

edit: Lemme explain a little about this "the 7.3 internals can't handle 500 hp" myth. The real difficulty lies in the HEUI injectors and their IDM driver. The injectors can't respond quick enough to flow massive amoutns of fuel at high RPM. Since they can't rev up high, the only way to deliver massive HP was to produce more torque at lower RPM. There's a big torque requirement in delivering 800 hp at 2800 RPM versus 800 hp at 4000 RPM.

The tuners now have been able to partially break some of the RPM limitations, plus they have smoothed out the power delivery so it doesn't bash stuff to pieces. Up to 500 hp is easy without major engine mods, the head studs and head gaskets are the weak link then, but I can't address life in the 600 hp region....my wallet only goes to 400 or perhaps 450.

 

[WH401]

Try 823 hp on spray, you really need to get out more.

638 fuel 823 on N20 - Powerstroke Nation

We need to get out more?, your the one showing it to us on an internet forum. Though it's interesting to see that the 7.3 needs drugs to make that power in the first place.

 

[powerstroke444e]

Lets be honest if you need that kind of power you should buy a semi. If you are just wanting to burn the track up get a race car. If you want to pull the sled out the back buy 2 engines and build one till it breaks and back off just a little on the second one.

I have not seen a 1 ton truck with a big enough rearend to handle 600hp diesel HP little own with a trailer on it? Most of the high numbers you are talking about are for a 15sec pull down the track. I do like seeing these, but they don't help the OP unless he is wanting to set land speed record pulling his camper.

That being said said I have over tuned a old 444 7.3L with out a turbo on gas and had to pick up the crank of the road. It sounds more fun than it was. They all can be blown apart if you don't know what your doing.

 

[Builder]

DMAX & 5.9L Cummins are already both over 1,000 HP. No 7.3L or other Ford diesel for that matter that I'm aware of, have made it even close to that.

Maybe the Taco will finally get them there?? Everyone knows the 7.3L powersmoke, the 6leaker and the 6.4 flamethrower can't do it.

 

[jas67]

DMAX & 5.9L Cummins are already both over 1,000 HP. No 7.3L or other Ford diesel for that matter that I'm aware of, have made it even close to that.

Maybe the Taco will finally get them there?? Everyone knows the 7.3L powersmoke, the 6leaker and the 6.4 flamethrower can't do it.

Um, I think this thread has wondered WAY off course.
I'm looking to tow a camper, not compete in truck and tractor pulls, or drag race.

If I could get the Cummins in the Ford Super Duty, that is the way I'd go. I'm not impressed with either the Dodge or Gov't Motors trucks (both have goo d engines). The Fords seem to be the best overall package. If I'm buying a < 150k mile truck (I've decided to stay under 150k) then the differences between a 500k mile engine, and a 300k mile engine doesn't matter. The ability to hot-rod the engine to 1000 ft*lb is cool and all, but I don't need it. The stock 7.3L intercooled Powerstroke is just fine for me. I do know to avoid the 6.0.

Speaking of the 6.0L, did they ever resolve the problem? I found a decent deal on an '06 F-350 Crew cab. That is the 3rd full year for the 6.0L -- did they get it right by then?

 

[Dargo]

Speaking of the 6.0L, did they ever resolve the problem? I found a decent deal on an '06 F-350 Crew cab. That is the 3rd full year for the 6.0L -- did they get it right by then?

Per Ford, the 2006 6.0 PSD engine has had the least warranty claims of any engine in a Ford that year. After my Dodge started getting old I debated about getting an older 7.3 PSD or a later model 6.0 PSD. I ended up buying an 2006 F350 with the 6.0 PSD in it and I've been very impressed with it. To stay in your target range and for your mentioned needs, I think you'd be happy with a '99 to '02 7.3 PSD. There are more of them out there to pick from than from Dodge or GM since more were sold. That gives you better odds of finding the right truck for your needs. Good luck!

 

[Diamondpilot]

I do know to avoid the 6.0.

Speaking of the 6.0L, did they ever resolve the problem? I found a decent deal on an '06 F-350 Crew cab. That is the 3rd full year for the 6.0L -- did they get it right by then?

Why avoid the 6.0? I have 2 and they are the great. I have never owned a Cummins but have had a 7.3, these 2 6.0's, and a Dmax and both of mine have been trouble free and by far the best diesels I have owned. They are very powerful and easy and cheap to upgrade to not only add Hp but improve the fuel consumption. And yes, you are right about Ford having the best overall package.

The issues with the 6.0 was solved by early 2004 build date trucks. Late 04's and there after should be fine but you can get a lemon on anything. My 04 has had zero issues with the entire truck. My 06 has only had a bad fuel gauge and the dash cluster needed changed.



Chris

 

[RobertN]

I thought the same; I had Ford's before(F250 4x4's), albeit gas engines. They were great trucks, especially my '89. Sold it with 225k on it; that 351 ran like a top still.

My Dodge has been great. I still like the Ford's and would consider one if I were shopping. But, my Dodge has been great, as has the Cummins.

I personally, would not get GM, mostly because I like a straight axle truck suspension in a 3/4 ton or heavier truck. The motor/tranny is probably great, the interior is probably nice. But I do use 4wd, hunting ect. That low slung GM IFS just, well, aint the same. But, I also grew up in solid axle Jeeps too...

I would look at the truck that fits you best. Stock, the "Big-3" are pretty evenly matched.

Um, I think this thread has wondered WAY off course.
I'm looking to tow a camper, not compete in truck and tractor pulls, or drag race.

If I could get the Cummins in the Ford Super Duty, that is the way I'd go. I'm not impressed with either the Dodge or Gov't Motors trucks (both have goo d engines).