Best oil for 6.7 Cummins

[Zidade]

This might've been already discussed, but couldn't find something that answered my question. I'm looking for a oil that protects, but at the same time improves fuel mileage. Is T6 5W-40 a good engine oil for an Eastern NC truck? What oil are you guys running/recommend?

[rebelrouser]

I run T4 15w 40 Rotella in my 99 dodge diesel, 350,000 miles and still running great. Your 6.7 has the newer emissions package and just like cars, the tier 4 engines don't like the zinc and other wear additives, it fouls the catalyst in the after treatment. The T6 5w40 Rotella should work good. My main issue is to change the oil regularly even though it is expensive since a diesel holds so much oil. Soot contamination of the oil from blow by is the main thing that will destroy your engine. The other thing I have seen is leaking injectors that the owners ignore because the truck still runs OK, many times, the fuel wash will destroy an engine. I check my oil to check the level, diesel sometimes start gaining oil, that is a super red flag many people don't catch. My old dodge for example had an o-ring start to leak on an injector and it did not affect the running at all, but the oil started to gain. Some guys drop a little oil off the dip stick on a piece of white paper to look for a fuel ring from time to time.

https://www.machinerylubrication.com/Re ... ntaminants

[Rick!]

What year 6.7?
I use the T6 in my 2017 ECOdiesel but I believe I used whatever the 15W-40 Ro-smella in my 2013 6.7. I don't remember if it was T4 or T5.
In the winter, I changed oil weight but you shouldn't have that concern in NC.

[engineguyBill]

I use Valvoline 15W40 Diesel oil with good results.

[pdq67]

Is, "URSA", brand oil still used in diesel engines?

pdq67

[allencr267]

... I check my oil to check the level, diesel sometimes start gaining oil, that is a super red flag many people don't catch. ...

Catch it and destroy all the pride & bragging rights of not burning or using any oil.

[MELWAY]

What oil change intervals are you guys at with these diesels

[77cruiser]

10000 miles.

[Rick!]

10000 miles.

^^^This. My 2004.5 5.9 was 7500 miles

[Truckedup]

What does Cummins suggest for oil?

[chevyfreak]

What does Cummins suggest for oil?

Some hyster forklifts uses qsb 6.7 engines and cummins(here in za) endorses the valvoline premium blue oil as engineguybill noted. We use it where certain customers prefer it but normally we use shell rimula 15w40 diesel oil. Engine failures is due to overheating or not doing service intervals in time or oil level. Never had one due to oil itself.

I use Valvoline 15W40 Diesel oil with good results.

Chevyfreak.

[Krooser]

I have had better results in my big diesels with Delvac...better oil samples with higher TBN numbers after a 50,000 mile oil change interval. Lucas and Schaeffer are very good, too. Rotella always fell short.

[Krooser]

Is, "URSA", brand oil still used in diesel engines?

pdq67

Still available but I don't know anyone who uses it.

[MELWAY]

I have had better results in my big diesels with Delvac...better oil samples with higher TBN numbers after a 50,000 mile oil change interval. Lucas and Schaeffer are very good, too. Rotella always fell short.

Are you referring to delvac 1 full synthetic? 50000 is a long time for oil to be in an engine

[cjperformance]

I have had better results in my big diesels with Delvac...better oil samples with higher TBN numbers after a 50,000 mile oil change interval. Lucas and Schaeffer are very good, too. Rotella always fell short.

Are you referring to delvac 1 full synthetic? 50000 is a long time for oil to be in an engine

We used to run Urania 5w30syn in 3 Iveco Stralis rigs, 80,000km(50,000ml) oil changes going off of oil sampling. At ~1,000,000km we switched the Iveco's to 15w40 Delvac mineral, same as we ran in the Sterling Cat C12 & Eagle C15 at the time, both of these had done 1,300,000 and 1,200,000 respectively at the time (running 30,000km oci's)
The Delvac was WAY cheaper than the Urania SYN. Economy was not affected, 900-1000km round trips per night, oil analysis came in to show the Delvac good to 60,000/65,000km in the Iveco, so the price difference V the slightly shorter oci and less inventory on oil made running costs cheaper on the Delvac mineral!