The Detroit Diesel 2 Stroke Lubrication Debate

[bigdig4]

I have read many articles on whether the proper oil for a 2 stroke Detroit Diesel is a straight weight 'i.e. SAE 30, 40 or 50 or a blended oil such as 15w 40 and there are arguments for both sides as to which one to use, however I just bought a Spartan Fire Truck with a Detroit 8v92TA DDEC engine and have included as a attachment the Specification chart from the manufacturer (Spartan Motors Inc) that lists the recommended oil as 15w40. Thoughts anyone?

 

[nwjones18]

I say run 15w40. Welcome to BITOG!

 

[JavierH19]

I believe anything that is cf-2 rated can be used and some but not all 15w40's are rated for it. There was a thread on here with the same question.

Found that thread i remember looking at years ago while i was a lurker. But this answers your question more or less.

https://bobistheoilguy.com/forums/threads/15w-40-in-a-2-stroke.150791/

 

[bigdig4]

Thanks guys, I'm kinda on the fence either way I know we always ran Sae 30 in our 71 and 110 series Detroits years ago without any problems ever and at that time no one even mentioned 40wt, however oil technology has changed a lot since then and one has to wonder is newer better or is there no school like the old school? How about a compromise maybe run Sae 40wt normally and every 4th oil change use 15w40 to remove the deposits left by a non detergent oil? Or a straight weight oil with a some kind of a supplement? Lets take a final poll please finish your reply with a yea or nay on straight weight SAE40 regardless of brand and I will tally up and count the vote at the end.

 

[ripcord]

Rotella T1 40 SAE has the low ash content the Detroits are supposed to need but still has an additive pack with detergent and anti wear additives.

https://shop.sclubricants.com/rotella-t1-sae-40

 

[bigdig4]

Rotella T1 40 SAE has the low ash content the Detroits are supposed to need but still has an additive pack with detergent and anti wear additives.

https://shop.sclubricants.com/rotella-t1-sae-40

If only R.E.M. used the right ATF

 

[bigdig4]

Good point and thank you Ripcord. My other concern with a straight weight oil is they were developed before turbochargers were ever introduced, however the T1 Claims to be appropriate for both turbo and non turbo applications.

 

[ripcord]

If only R.E.M. used the right ATF

You're the first one to mention getting that song reference.

 

[bigdig4]

You're the first one to mention getting that song reference.

Sometimes you have to read between the lyrics! Humble beginnings begin with the single blow of a horn man.

 

[zrxkawboy]

If only R.E.M. used the right ATF

As long as they don't use the Dexron 2 recommended on your pictured label!

 

[bigdig4]

As long as they don't use the Dexron 2 recommended on your pictured label!

what if the engine identifies as trans?

 

[ripcord]

Ha! If Spartan motors can't even get "Dexron" right, I'd be hesitant to give too much credence to their oil recommendations.

 

[bigdig4]

Ha! If Spartan motors can't even get "Dexron" right, I'd be hesitant to give too much credence to their oil recommendations.

And "AUTOMATICALLY" we have spell check

 

[bigdig4]

And "AUTOMATICALLY" we have spell check

Monkey is for nothin and your chimps for free.

 

[ripcord]

Monkey is for nothin and your chimps for free.

And there's the old Christmas favorite, "While shepherds washed their fox by night"

 

[bigdig4]

And there's the old Christmas favorite, "While shepherds washed their fox by night"

And John Fogerty sang "theres a bathroom on the right"

 

[joegreen]

My assumption on the 15w40 recommendation is probably because the trucks could end up in cold climates and usually fire trucks are started and driven to the scene rapidly. It’s better to have a good flowing oil

 

[Highboy]

30W winter
40W summer
Don’t use multi grade oil!!!

 

[ka9mnx]

30W winter
40W summer
Don’t use multi grade oil!!!

Agree with a slight modification.
SAE 30w Artic conditions
SAE 40w All other conditions

I worked on Detroit's for almost 30 years. When 15w40 came out 15w40 was tried on the Detroit's and they all consumed oil. My son, presently, works on 71 series Detroit's for the Government. When a new contractor took over his company they changed to 15w40 and my son told them it was a bad idea. Result, higher oil consumption. He wrote a letter to corporate and they finally went back to SAE 40w.

Due to the fact they are two cycle and have a unique cylinder liner design (air box in the block with oil drain holes), They naturally consume (leak) oil. But marginally more with multi grades.

 

[64bawagon]

We ran 30wt Delvac 1230 in all our 2 stroke Detroits. We had a pair of 6V92's and two 8V92's. When I retired they were all over 20 yrs old and still going strong.
The Detroit manuals that were original to the trucks called for either 30 or 40wt. Although these trucks were in heated conditions during the winter they were at 100% throttle for the first 4 or 5 minutes once they lit.