What oil to use?

What do you recommend to use for engine oil...brand, grade, etc...
Thanks,

Warren

I use 15w-40 shell. Seams to stay clean a bit longer and hold a higher PSI. The data plate says 30w but for what oils are today compared to even 5 years ago a 15w-40 works very well.

shell rottela 15-40 is my personal fav!! just remember to always change it every 3000 miles, diesel oil gets dirty very fast..

I run the Rotella in my Freightliner at work and service intervals of 40000 miles when new and reduced to 30000 at 500k then 20000 at 750k. Truck was still running fine at 927k then they gave me a new one. Diesel oil has additives to it to cope with the extra pollutants that end up in the oil.

I ran straight 30W Castrol in my 86 M1009 Cucv, but I ran rotella in my Duece, If you have deep pockets there are expensive synthetics
like royal purple and amsoil. Alot depends on your climate where you live if its cold alot of the time <32 degrees stick with a lighter weight oil like 15W40. But if you live in sunny CA, I would run straight 30W.
Just an humble old motorheads opinion.......

I'm switching from 15/40 to SAE 30 next oil change myself.

For those not Rotella fans; I use Chevron Delo with good results. Make sure whatever you put in your diesel is diesel-rated. Ratings starting with "S" are automotive/gas engine. "C" denotes oils formulated to use in diesels. I'll post a guidechart to the TA section that explains it pretty well.

Since we are on the subject of oil, I am going to change my tranny oil when installing my new PTO. What grade,brand, quantity is recommended for the duece tranny? I could'nt find it in the manual.

GL-1 straight 90W, or any newer high-pressure rated GL-5 IF IT plainly states "safe" or "compatible" with yellow metals/braes. Use this for your trans and transfer as they have brass synchros and can be damaged by moderln lubes not designed for that service.

Use any old 90W in the axles if you like, there is no brass there. Synthetics are a waste of $$ in my opinion, you won't make any noticable difference with them and they are boucoup $$ besides.

The drive system on these trucks is very robust (other than the one countershaft race in the 3053-A trans), and just keeping them wet is enough to let them run a very long time.

dg

Im changing my fleet stuff over to synthetics right now so the truck is going also.. I have been on 30W for years and years but with the cost of oils and filters going up like they have been the synthetics are not looking so bad especally when your looking at a fleet of small stuff which is hell keeping up with!!!

So the POS, (formerly called a M35A2) that I have will be getting Rotella 5W40 Syn... I went with this because I needed a product that I could get in quarts, gallons, and bulk for my tanks... Cant wait till I buy in the first bulk batch of 300 gallons LOL... Should be a heart stopper of a bill!!!

I am going with Shell Spirax which is also syn on gear oils... 80-90 on the trans and 80-140 on the axels... The trans I might play with a bit and try a 50W truck fluid which is said to give easier shifting but I will give the 80-90 a run first...

The advantage to synthetics are longer miles between oil changes and
they are able to resist heat and take longer to break down.

People could debate oil all day long like chevys vs fords it all depends
on which you prefer

Oil is like small ball bearings different sizes. when the bearings are pushing on then the bigger ones have more pressure on them. In synthetic oil all the ball bearings are the same size. The pressure is even among all of them so it takes longer for them to breakdown.

Imagine 10 guys of the same height carrying a heavy log. Now imagine 10 guys carrying the same log but 5 of the guys are midgets and cannot reach the log. now 5 of the guys are taking all the pressure.

So when does the Dwarf tossing begin??????????

I have 2 observations on the Synthetic stuff vs dino oil.
1) Cost. Synthetics are pricey
2) Leaks. These old gearboxes don't do so well in keeping the slippery expensive stuff in the box where it belongs.

Yes, usually one should try to run synthetic in a low milage or new vehicle straight from the get go. It kinda defeats the purpose putting synthetic oil in a car with 70K+ in it.
Now if that same car had been run with synthetics since semi new, when the engine is torn down the friction surfaces have less wear than dino oil.

Like I said it is a Ford vs Chevy thing....Some men like Blondes, Some like Brunettes...

Jones said:

For those not Rotella fans; I use Chevron Delo with good results. Make sure whatever you put in your diesel is diesel-rated. Ratings starting with "S" are automotive/gas engine. "C" denotes oils formulated to use in diesels. I'll post a guidechart to the TA section that explains it pretty well.

Click to expand...

Our Chevy 6.2 engines specs asks for CG-4 oil rating, you can go higher to CH-4 or CI-4 but now lower like CF-4.

This rating is needed for properly lubrication of the roller lifter bearings.

I´m a huge fan of Chevron Delo 400 too. My other choice would be Mobil 1.

I am a rotella t 15w40 man i have over 200,000 on my 95 dodge with cummins motor no problems with motor.

the 5.9 cummings motor kick ass!!, I have never heard anyone complain about them.
Everybody loves the 5.9!!

IS there any harm in running diesel oil in a gas engine? probably a kinda dumb question, but I like to know these oddball things.

I don't think that the diesel oil additives would protect a spark ignition system properly. I wouldn't try it.