Rotella T6 vs. Mobil 1 TDzl Truck: CG-4 rating

[3930dave]

Background:

Just bought a 2001 7.3 PSD. Ford's spec was CG-4/SH for that engine.

I'm working on understanding if anything/what may have been compromised (additive deletion?) with the migration to CI/CJ, but for the moment. let's assume that I want to use an oil that is explicitly rated CG-4. (Not looking to recycle (pun intended) any oil wars here.... I get that using most any decent oil at the regular service intervals is 95% of the battle).

Canuck boy here, so I want to run synthetic for the low temperature performance, so will use 5W40.

Q) Has anyone recently queried Shell or Mobil concerning the CG-4 certification on these products ?

Mobil's site lists TDTruck 5W40 as being CG-4, while Shell's site does not list CG-4 for their T6. Fast forward through 3 shopping trips (my wife deserves a medal for patience on this)....... I found the opposite to be true - Mobil does NOT list CG-4 on the TDTruck jugs at Wmart, but the T6 I ended up buying at CTC DOES list CG-4 explicitly on the jug.

Supply chain delays could explain the Mobil story, but not so much for Shell....

??? D.

 

[Happyman]

If the rating is at or above the CG level (ie: CH / CI / CJ ) then it also covers the CG level and any previous rating below that. Just because it isn't listed on the container does not mean it does not meet the CG spec.....as long as the other spec numbers are at or above the CG rating. The ratings change in alpabetical order.
Hope this did not confuse you more :confused2:

 

[3930dave]

Thnx HappyMan........ that retro-coverage of new specs is what I'm used to in the gas (S*) world. I'm new to the onroad diesel world, so am trying to get up the maintenance learning curve fast, but correctly.

Urban (or in my case, rural) legend has it that when the new generation diesels came in with more complex emission system, the truck manuf. leaned on the oil industry to back off certain anti-wear additives, mainly to get longer lifespan out of the catalytic converters..... I don't know enuff yet to decide how true this story is.

In the gas world, I'm used to seeing JUST the latest S* spec (ie. SL,M). The diesel oil guys seem to list MANY of the older specs, as well as the latest one... that is one reason I'm trying to research the above story a little more. I can see where regression testing may be required to certify that a new oil really does meet an older spec.... all that takes time/money, so I get why some oil manuf. may not bother.

The tiny bit of reading I've done on this has turned up examples of engine manuf. getting really bent out of shape about diesel oil certification, up to insisting that an OLDER spec of oil be used to maintain warranty.

I don't have to worry about warranty.... just trying to filter fact from legend...

D.

 

[brucew44guns]

I bought a 94 Ford F-350 brand new in 94. I used Delo 15-40 from the start. During all that time, that number crept up on oil specs. At 250,000 I sold the truck and it did not use asny oil on 3K changes, original injectors, good oil pressure, no smoke, no problems. The truck is used by a farmer now who works it hard everyday as a bale feeder truck on rough grouind plus other chores. If I still had it, I would not worry about pouring in CJ-4 spec oil.

 

[2458n]

I think with the frequency of your oil changes you will be well served with any diesel rated oil. We often see fleet maintained trucks over 350,000 on gas engines. A Mack came thru with 650,000 miles and had nothing done to it. The clearances on the engines as well as the oil improvments are making for some long lasting products,

 

[3930dave]

Some guys around here will run 15W40 year round, based on my experience with my ag tractor, I prefer to use a good synthetic 5W40 dzl oil, to deal with our winter cold snaps - I sleep better at night, and if nothing else, it is a lot easier on the starter and batteries.

I'm not a total conspiracy theorist (at least not quite yet ), but I do retain what I consider to be a healthy amount of skepticism with regard to "new/improved" standards - ie. I don't recall any publicity regarding fuel mileages declining with new fuels and emission systems, but real world data seems to prove that out.

I hear you guys, regular maintenance with just about any decent oil is virtually all of the battle - but, I've learned to trust my instincts... something "feels" a bit funny about how these major oil companies present their C* ratings - it may be nothing more than their marketing depts attempting to deal with the legends that have emerged, or there may be some truth regarding the spec deltas.

Winter is coming, I'll spend some time (hours?) wandering thru bobistheoilguy to see what I can learn... I have a few Eng. buddies, but unfortunately none are on the Petro side of things.

Thnx for the comments. D.

 

[Diamondpilot]

Both are good oils. I change the oil in one customers Dmax and we use the Rotella 5W40. His brother has a Dmax also and runs nothing but the Mobil 1.

I have had 4 diesels and I have used Castrol 15W40, Dello 15W40, Delvac 15W40, and Ford Motorcraft 15W40. Never used a single drop of Rotella personally in any of my trucks. I just buy whats on sale and change it a 5,000 mile intervals. Have nothing against Rotella, ran it in diesel tractors for years. Just do not like it for Ford Diesels with hydraulic injectors.

Chris

 

[3930dave]

Thnx for the feedback Chris.

My neighbour was teasing me "Given how long you hang onto vehicles, you better put that 7.3 in your will". I'm planning (knock wood) on sticking around for a while, but he does have a point - I do plan on having this 7.3 for a looonnggg time, so am trying to learn as much as I can.

Do you have any technical,empirical, or gut feel reasons for NOT using Rotella with these Hyd. injectors ? I have to admit to being a little concerned about the injector design initially, but after doing some research and talking with a local Ford wizard, decided to go for it.

Might be my imagination, but it does seem to me that I am getting turbo "whistle" a little more readily than b4 I changed the oil. Nothing crazy loud, just softly in the background - I think this is normal - never had a turbo b4, but have heard this subtle sound coming from many smooth running highway tractors at speed. Kinda wondering if the old oil was broken down enough that the turbo was not spinning as freely - no driveability issues when I got the truck.... just my obsession with details.....

The truck was fleet maintained - maintenance and fluids were pretty good, but it might have been some old conventional motor oil - I don't really know how long the truck had been sitting.

5,000 miles is the Regular (not Severe) service interval, I won't be going past that with the truck as currently configured. Rgds, Dave.