Hi all,

I'm new to diesels. I just bought a 2004 F250 with the 6.0 V8. I have the high and low circuit, contribution codes on cylinders 4 and 8. I've only had the truck for a few days but I've been reading a ton. The symptoms are hard start, rough idle/shaking, no power when cold. When it heats up and I'm over 2000 RPM it seems to be just fine. Even when hot and below 2000 RPM it does ok. I've check the FICM. It reads 48V with key on and 48V running. My plan is to do the following:

Change the Fuel Filters
Change the oil filter
Change Air Filter
Change oil with 5-W30 synth and I have both Hot Shot/Rev-X

If that doesn't work, I'll replace the two injectors.

How does that sound. Any help is appreciated.

 

I HAD A 6.0 AND THE DEALER TOLD ME NOT TO USE synth. I DID 6 INJECTORS OVER AT 60K

 

Moved to the 6.0L forum.

 

Check the FICM connectors. Check the injector plug and ohm both the injectors and then buzz test it.

 

Your "dealer" was woefully misinformed, or just plain ignorant handing out such poor advice. 6.0 does splendidly with syn oil.

 

That dealer/person is very mis informed on the 6.0. I've had mine since brand new in 2005 and since I've switched to syn 5 30 the injectors love it and it runs better than ever. I would even advise a new 6.0 owner to run it and I would bet that most anyone here would.

 

Contribution codes were for 4 & 6. Could be the harness for that side.

 

So 5w30 over 5w40 & 15w40?

 

I think TT means 5w40..........something like Shell Rotella T6, a favorite here.
There are other brands as well that are fine....need to be something diesel grade though.

 

Gotcha. Running Amsoil 15w40.

 

5-30 is too thin for these trucks.

You want to run a diesel rated synthetic 5w-40 oil for the best performance of your injectors. I personally use rotella t6, but any synthetic diesel oil of that weight will work well. Everyone has their own favorite, but the rotella is easily found and is pretty well priced at walmart and online, so it is a popular choice here.

If you are having rough running while cold, but not warmed up, that sounds like classic stiction to me. I have heard of good results with archoil for that. If the synthetic oil, new fuel filters and an anti-stiction additive (archoil, rev-x, hot shots) don't help much, some new injectors may be in order.

Good luck and congratz on the new truck.

 

there are more than a few running 10w-30 synthetic oil, 5w-40 is good to run year round. It helps with starting in cold conditions, helps with stiction as well.

 

Sorry about the confusion. I guess I need to proof read my stuff before putting it out there. Shell rotella t6 syn 5w40.

 

Just make sure in the whole conversation that you check your FICM voltage when the truck is STONE cold. A warm engine has caused many a FICM to seem a-okay when it is in fact the culprit.

 

Wanted to follow up on this. I did all of the above (Used Rotella 5-40) and drained the water fuel separator. I added 8oz of Rev-X and 2 quarts of Hot Shots. After 5 minutes of idling, all codes were gone and idle drastically improved. Still not 100% but,much much better than before. I drove it on the E-Way, the only thing I noticed was vibration somewhere between 1500-2000 RPM. I'm thinking that's something to do with the turbo. Also, I still have the lack of power during cold starts, but I'll give the additives 1000 miles to see if it helps.