Ok, I think where I'm at is I'm going to start by addressing the injector o-ring issue and then decide what to do on the hpop. I'm pretty sure I'm going to,replace the injectors versus just doing o-rings because I just can't see putting a set of high mileage injectors back in. With that decision where should I get injectors from. I keep reading about 160/80 injectors etc. should I be looking at bigger injectors since I pull regularly? Currently our fifth wheel weighs in about 10000 pounds but will probably upgrade before I get rid of this truck into a unit weighing 12-13k loaded. Looking for insight before I drop the coin. I will at some point probably get a hydra and s&b intake and of coarse I already have the 38r turbo with 4 inch exhaust.

This is only my opinion, so take it for what it is worth.

My truck runs great on OEM AD injectors, so much so that when I replace mine I will seriously consider stock replacements.

If I choose to upgrade, I will only purchase NEW 160/80 injectors, probably from PIS. That is only because of the research I have done and the decisions I have made in my mind.

A lot of fellas go with remanned or even recently rebuild their own. I don't think I trust myself enough to rebuild them, and have seen too many stories about remanned needing to be sent back. I am willing to spend the extra money to get new and let it be. We plan to use the truck for RV'ing full time/a lot of the time in the future and I do not want to second guess my decision while diagnosing an injector failure on the side of the road somewhere.

New injectors will/can fail too, but much less of a chance.

I will not go any bigger than 160/80 because that suits the goals for my truck as a tow pig. The 160/80 and KC38R should get me near 400 HP and equivalent torque, which is plenty enough to get what I need done. This is one of the reasons why I laugh at the newer diesel owners that claim you need 500+ HP to tow a 5th wheel, but then when you bring up the fact that trucks have been towing 5th wheels and farm trailers for decades, they just say well it is more efficient. Perhaps, but I know that my bank account would not be nearly as efficient with a newer diesel. I have about $13K into my truck and it pulls the trailer up the Rocky Mountains just fine.

The decisions ahead of you are not easy because there are many choices. But, you need to be sure because injectors are a large investment and can be very time consuming.

to the OP....If I could wind the clock back to my injector purchase, I'd likely go 160/80 over the 160/30 I have. Not that I'm unhappy with the 30% nozzle, just that there are more gains in EGT reduction to be had with the 80% nozzle.

400Hp should be around 800ft/lb torque....plenty of both!

I guess it could, but it would have to pass through the HPOP to do so. It's a very similar comparison to a blown head gasket filling a cylinder with water. Even with cracked rings, my 300 I-6 didn't drain after a week just sitting there. I'm not trying to belittle your point, but for the life of me I can't imagine it draining enough to matter overnight.

We're getting a little deep into the weeds here, but the HPOP is a positive displacement pump, I think it's seven pistons. In order to generate pressures as high as 3500psi, I can't see how oil can easily leak through it when it's not moving, so while some may seep through when parked, and some can seep through a failed injector o-ring while parked, I doubt very much it would be noticeable overnight. And if those leaks were large enough to noticeably drain the reservoir overnight, then I doubt they would generate enough ICP to start the engine, much less reach 2900psi during operation. If you parked a brand new 7.3, then came back to it a year later, absolutely I would expect the HPOP to be low or even empty.

If I go to the bigger injectors will I need custom tuning immediately to be able to get the truck to run right? Sous, I will probably go with new injectors versus rebuilds anyhow. Do you have a link to the injectors you are suggesting? The only place I've considered remans from is rosewood diesel and that's just based off the good things I've read here about them.

Yes, if you change from OEM AD (split shot) to 160/anything you will need custom tuning. The 160/anything are single shot injectors which must have custom/different tuning than the OEM AD injectors.

http://www.performanceinjectionsystems.com/

The above link is to the PIS injectors. They do not have 160/80 listed on their site, but you can have them make anything you need with a phone call. I lean toward PIS only because of the reviews I have read on here in the past. I have traded PM's with some of the old hat members here that have a lot of knowledge on the injector choices and PIS has been among the best talked about. I know Unlimited Diesel has a lifetime warranty on their injectors and seem to have very few problems, but something in my head tells me PIS is the vendor for me.

I would invite you to look at the bigger names in injectors like PIS, Swamps, Alliant OEM, Unlimited, etc... and make an educated decision based on what your heart and mind tells you. The perfect solution for me may not be for you.

Take your time and digest all of the information. Then, when you have finally made a decision, sleep on it and see if you feel the same way the next day. This is a large investment (for me anyway) that includes not only the injectors, but associated parts and pieces too. You may find you need new cups, UVCH, sensors, pigtails, etc. These things add up quickly.

Keep us posted on what you decide and remember, we love to see pictures of other people working.

It will start and run, but the throttle is going to be SUPER touchy...Tugly can share on that.

A single failed O ring probably wouldn’t be noticeable, but I had the same problem. Reservoir would drain after a couple of days sitting, ICP would build enough to start with cold oil, but wouldn’t restart when warm, no oil in the fuel filter. I did the Cody test and immediately heard the gurgling under both VCs. 6 injectors had failed upper tings and 2 showed erosion which lined up with the gap in the steel rings.

I can’t explain how the oil leaked past the HPOP. It doesn’t make sense to me either.

Ok I had another hard/almost no start this morning. Just looking for an opinion. Could that be due to the orings being bad on the injectors? You can watch the icp sit at zero and as your cranking it finally starts to go up and build slowly. Then all of a sudden it takes off and builds the 500 plus and fires off. Runs normal and you have no more issues after that. If you stop somewhere and come out while it's still warm it fires off in about 2 seconds just like normal. I'm just wanting to rule out the hpop still. My plan is to do the injectors and then see what happens but I'm just curious on everyone else's opinion.

If your looking to upgrade or going for stock check out www.Americandieselinjection.com the guy has the best price and customer service you can ask for. I got a set of hybrids from them and I'm very happy

Freeland, MI huh? Well, I'm sure it's cold out there, but here's check you can do to see if the low level is the issue. Before you start it tomorrow morning, note the HPOP level and then fill it to proper level. Give it a minute for the oil to fill everywhere - which is probably the time it takes to button it up and warm your fingers - and then try starting it.

But something else. Have you checked your fuel filter yet? Bad injector o-rings leaking oil into the fuel side will generally show up as a blackened fuel filter after some time.

Yea I have oil up at the fuel filter, it was black when I changed it last Monday when my fuel gelled up. I did fill the reservoir last week when I found it was low and tried starting with no change at that time. When we do the injectors I'll be putting another new fuel filter and an oil change at that time again also.

when it's really cold out and I start my truck from sitting overnight it will run for 30 seconds and die and I have no low pressure oil on the gauge and I have to try it a few times before it will start and after it runs for about 40 to 60 seconds my oil pressure gauge will go up but if it's warm out it fires right up without a problem

Well I decided to go with a local shop call Diesel injection specialists I bought brand new Alliant injectors, stock everything. Only thing they told me that I wasn't aware of is he said number 8 injector is different than the other 7. Something about chatter or something is why that ones different. Any input on this. These guys have come highly recommended locally and I did buy some stuff from them for my 6.0 and was happy