'03 - 268k miles - what kind of maintenance recommended at high miles?

[dmsexton]

Hey guys,
My '03 is getting up there in miles, 268k, and other than regular oil and filter changes, fuel filter changes, differential and transmission servicing, my truck has never really missed a beat. I have put in new brakes, batteries and I did replace the water pump/hoses/radiator/thermostat and coolant. But other than that, what else should I be worried about doing to it? It hasn't given me any issues to speak of and runs like a champ, gets great mileage. I just want to make sure I'm taking good care of it so it will last another 268k.
Thanks in advance!
Details: 2003, SO engine (235 horse), 47RE transmission, 3:54 rear end. Runs Shell Synthetic, Cummins oil and fuel filters. Doing oil samples with Blackstone Labs @ around 10k-12k.

 

[Prairie Dog]

Wow, that's great - so much for the weak trans BS eh?
I wonder tf there's a point at shich it just makes sense to do injectors rather than have one fail on the road or maybe even damage a cylinder.

 

[cerberusiam]

Injectors, transmission, ball joints, steering parts, steering box. You don't list shocks as replaced but way past time to do that if not newer Bilsteins. Front springs are probably feeling the age and not functioning as well as they could. OE lift pump is probably looking for an excuse to quit. The truck is 13-14 years old, that will take a toll on parts even if they don't break.

FYI, you have a 3.73 gears unless they were changed. The AAM axles don't have a 3.54 ratio.

 

[MarkEkberg]

I'm kinda in the same boat at 225K

I did a few things just to do it like idler bearings and a belt. OE was still on it at 200K when I bought it.
I service front wheel bearing units every other year.

Currently trying to find a single piece drive shaft as all the joints and carrier are smoke in mine.

And I have a random no start which is leading me to injectors, but I am not in a position to drop 3K on something that might not be the problem.

 

[dmsexton]

Oops, forgot to mention I did put Bilsteins on it. Belt and pulleys are good,
Cerberusiam, I think you're right about the rear end ratio.
Also forgot I did have the front upper and lower ball joints done, and had the outer u-joints replaced at the same time. Just also re-did sway bar end joints. Man, guess I forgot a few things... lol

 

[jhenderson]

Cerb, why would you list injectors? Kind of expensive for maint rather than repair.

 

[RWherley]

268K is real good for still having factory injectors, my dads 04 made it to 220 on the first set and and 180 on the 2nd set, when they start to go your mileage drops it takes longer to start when the engine is cold, and if they get real bad they start to make a ping or ticking sound

 

[cerberusiam]

Cerb, why would you list injectors? Kind of expensive for maint rather than repair.

The mileage and the fact it is an 03 with the older style injectors that were not as hard as the later ones. Factory filtration was 10um where 3um is the magic number for solids in an HPCR system so 268k of grinding away can leave some wear, 200-250k is the mileage one needs to start thinking about injectors. Melting a piston or filling the crank case with diesel while towing your 5'er to a remote campground is NOT going to end well, no matter what. Injectors and CP-3 are wear items with our crappy fuel and factory filtration so they fall under maintenance items.

A $2.5 bill for injectors is a lot less than $8-9k for a rebuilt engine,

 

[jhenderson]

I understand one must keep an eye on things but I sold my 04 with 385,000 on it with original injectors and factory filtration. The truck has over 400,000 on it now with no problems. At about 250,000 I thought, like you I should replace them out of caution but then read many reports of shorter lifespan on the replacements than the originals. I would agree with carrying a spare injector or solenoid.

 

[cerberusiam]

You got lucky, or, you have a good fuel source. They may work ok and there are no symptoms of problems but they are not any where near optimal past 200-250k. Most of the problems with replacements was due to using reman injectors when new was in short supply.