7.3 High Mile Maintenance

Sterling B. · Aug 3, 2017

2000 F250 is about to turn 355K and I've got maintenance on the brain. Is there anything in particular I should be replacing for good measure? Best I can tell is fuel pump is original as well as the oil cooler. Injectors are original with the exception of 1 reman in the #8 cylinder. Transmission just went through a complete HD rebuild in Jan/Feb, so that's good to go. All suspension is tight including unit bearings. (replaced with OEM in Sept. '16). Motor is tight with very little blow-by (turn cap upside down on fill tube and it stays put).

Are oil coolers an issue? Fuel pump is probably a good idea; any benefit to going with something like AirDog and sump? I guess the best thing to do is put a gauge on the fuel pressure... Truck doesn't make big power, just a DD and tow pig with loads north of 25K on occasion. Will be getting Geeerhead tunes at some point to replace the DP Tuner it has now. 6637 and 5" flo-pro are the only other "performance" items.

DEEZUZ · Aug 3, 2017

Id never ever suggest a race type fuel pump. Install a OE pump and leave your original under the seat. Look at how long it lasted you...

I suggest pulling the tank and doing the Driven Diesel pre filter kit. That extends life on the pump and entire system greatly. Also a RiffRaff fuel crossover. Its basically a poormans regulated return. I love mine, no priming necessary with fuel filter change really.

DEEZUZ · Aug 3, 2017

Do you send in for oil analysis? This will tell us wonders if its even worth doing anything to this engine. That milege is very high IMO, it wouldnt surprise me if we were starting to see some high levels of metals.

No issues with oil cooler, just seals. If not seaping I wouldnt even touch it then. At these high of miles your asking for issues with the end caps splitting while rebuilding it.

Original turbo? My gosh... GTP38R:thumbsup:

I just had my valve covers off for the first time(I think ever) and resealed my injectors for the hell of it. Thats my only worry with higher milege, is seals.

Magnum PD · Aug 3, 2017

Change the antifreeze recently?

psduser1 · Aug 3, 2017

Sterling B. said:
2000 F250 is about to turn 355K and I've got maintenance on the brain. Is there anything in particular I should be replacing for good measure? Best I can tell is fuel pump is original as well as the oil cooler. Injectors are original with the exception of 1 reman in the #8 cylinder. Transmission just went through a complete HD rebuild in Jan/Feb, so that's good to go. All suspension is tight including unit bearings. (replaced with OEM in Sept. '16). Motor is tight with very little blow-by (turn cap upside down on fill tube and it stays put).

Are oil coolers an issue? Fuel pump is probably a good idea; any benefit to going with something like AirDog and sump? I guess the best thing to do is put a gauge on the fuel pressure... Truck doesn't make big power, just a DD and tow pig with loads north of 25K on occasion. Will be getting Geeerhead tunes at some point to replace the DP Tuner it has now. 6637 and 5" flo-pro are the only other "performance" items.

Look at that, almost a grown-up engine.:toast:
As mentioned, check fuel pressure, coolant, etc.
At stock hp levels, the engines are capable of 5-600k miles.
Keep the fluids changed, swap suspension parts as required. If it starts having cold idle issues, swap some injectors.

If everything is doing what it should, don't mess with it, lol. Maybe change the axle fluid.

Sterling B. · Aug 4, 2017

Is the local CAT dealer still a reputable place to get oil analysis done? I'm not sure of anywhere else around Bryan/College Station who would send it off, besides me sending it to a lab myself. CAT dealer would be perfect since I need to change engine oil in about 800 miles and I've got one close. :thumbup:

Original turbo, need to upgrade it. I know one day it'll just destroy itself towing; it tends to surge bad pulling heavy, but so far it's tight. Truck had an easy life until I got my hands on it. LOL

Coolant was changed about 20K ago and has coolant filter, probably about time for it to be changed again. Is it worth upgrading from the old green coolant? Would upgrading extend change intervals?

Differentials get changed every 50k, but it's time for this again. Have the everything to do it, just haven't had time. :fustrate:

Anything else I'm forgetting?

DEEZUZ · Aug 4, 2017

Blackstone labs. $28, you just take a sample and send it in.

At this point I'd stay with green coolant. Just make sure the additive is in there and it tests fine. Definitely flush and mix with distilled water.

dsberman94 · Aug 4, 2017

I'd would ask jimdawg about oil analysis tests but I'm pretty sure blackstone is a no. He used Polaris labs and I'd go with them if he says that's who to use.

DEEZUZ · Aug 4, 2017

We're not analyzing a nasa rocket ship engine here.....

gwunter · Aug 4, 2017

So Blackstone labs is no good no more?

79jasper · Aug 4, 2017

Blackstone is fine.
Polaris tests for a few extra things included, while with Blackstone you have to pay extra. (Iirc)
Thing with Polaris through Jim, he'll give you his "reading" on it.

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dsberman94 · Aug 4, 2017

Something about their fuel dilution test being wrong when samples pulled at the same time were sent to multiple different companies for analysis and blackstone came back way off from the other two.

DEEZUZ · Aug 5, 2017

again, we just need to know if the engine is coming apart or there is coolant contamination. both of which blackstone can do for us. Im sure theres better tests but really I just suggested who I use.

ja_cain · Aug 5, 2017

Like Berman said, Blackstones fuel dilution test was way off. This will make it look like the oil is shearing due to the drop in viscosity. Jim also said they arn't ASTM certified. My brothef uses Intertek and SWRI at work (Afton Chemical). I think Jim said he has used SWRI to verify the polaris results. I would reach out to him as he is a certified tribologist and will be able to explain the results of the test in a much more comprehensive way. He is an awesome guy to deal with.

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Spatel23 · Aug 5, 2017

CTC DEEZUL said:
We're not analyzing a nasa rocket ship engine here.....

Bahahahahahahaha
Just too funny especially since we are talking 7.3 here

ja_cain · Aug 5, 2017

It is a really overengineered system that basically attempts to accomplish what the current common rail systems do. So, relative to other diesel injection systems it might seem like a nasa rocket. 6.0 is even worse.

Significant shear is going to effect the injection characteristics of these motors. Just the nature of how they work, so you should look for company that is going to accurately measure this.

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Sterling B. · Aug 5, 2017

I'll pm Jim and see what he recommends. I appreciate all of the input; post up if yall think of anything else that needs to be addressed!

CTC DEEZUL said:
again, we just need to know if the engine is coming apart or there is coolant contamination. both of which blackstone can do for us. Im sure theres better tests but really I just suggested who I use.

How many miles on your 7.3?

DEEZUZ · Aug 5, 2017

Clock shows 212k but being on tires it's whole life I imagine it's around 230k or higher. Speedo reads really slow

ja_cain · Aug 5, 2017

Sterling B. said:
I'll pm Jim and see what he recommends. I appreciate all of the input; post up if yall think of anything else that needs to be addressed!

How many miles on your 7.3?

Just shoot him a text or email him. Much better way to communicate. I guarantee he will respond to you right away if you do that. If you do your own oil changes I would also order some 8700 from him. It is a real good deal including shipping.

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Arisley · Aug 5, 2017

Mine just turned 375K when I sold it. Motor ran like a top. Every oil analysis I had (all two of them) said it was in perfect condition. Motor had no (as in zero blowby), last compression test (at about 350K said over 400 LB in every cylinder, all cylinders within 2% of each other. I once went over 25K miles between oil changes. Had to add a gallon twice. No clue where it went. I would use about a quart between 5000 mile oil changes. Never once a a problem with the motor.