Don't use 15W/40 in a Detroit two stroke

[willie59]

The old Detroit two stroke has been around for a long time, and although they are no longer a production engine there's still a pile of them out there. But a lot of things have changed since the days when those engine were common, specifically diesel engine oil. The multigrade 15W/40 used today is fine for newer engines, but it's murder for an old Detroit.

Detroit engines have very specific requirements for engine oil, mainly two, 1) use only SAE40 oil, no multigrade. If you're in an extreme northern climate you might use SAE30 in the cold of winter, but it's better to use a block heater to help keep the oil warm and use SAE40, and 2) the oil must have a sulfated ash content of 1.0% or less, the more less the better. Any oil 1.0% or above does not meet the engine oil specs.

This stuff is critical for the life of these engines. Use of the wrong oil, or use of multigrade 15W/40, will result in increased oil consumption and damage to the pistons and liners causing shorter engine life.

A few oils that meet the engine specs:

Chevron Delo 100 SAE40. Do not use Delo 400, it does not meet the sulphated ash spec.
Mobil Delvac 1240 SAE40
Chevron/Texaco Ursa SAE40 Super Plus

There may be others out there that will work, contact your local oil suppliers until you find one that can supply an oil that meets the specs.

 

[Oxbow]

Thanks Willie!

After reading your post I was trying to remember just what we did use. I believe it was Delo100 30W. The fellow I worked for had a 70 Pete with a 318 (8V71), a 5sp main box, 4spd brownie, Hendrickson pad or biscuit walking beam suspension, and a headache at the end of the day for the driver. I learned to drive on that truck.

He also had a JD 870A with a 6-71, and a Wabco 555 blade which I believe had a 4-53. I spent three years next to the 6-71 and have lost the high range of hearing in my right ear- and I wore ear plugs!

 

[LowBoy]

The old Detroit two stroke has been around for a long time, and although they are no longer a production engine there's still a pile of them out there. But a lot of things have changed since the days when those engine were common, specifically diesel engine oil. The multigrade 15W/40 used today is fine for newer engines, but it's murder for an old Detroit.

Detroit engines have very specific requirements for engine oil, mainly two, 1) use only SAE40 oil, no multigrade. If you're in an extreme northern climate you might use SAE30 in the cold of winter, but it's better to use a block heater to help keep the oil warm and use SAE40, and 2) the oil must have a sulfated ash content of 1.0% or less, the more less the better. Any oil 1.0% or above does not meet the engine oil specs.

This stuff is critical for the life of these engines. Use of the wrong oil, or use of multigrade 15W/40, will result in increased oil consumption and damage to the pistons and liners causing shorter engine life.

A few oils that meet the engine specs:

Chevron Delo 100 SAE40. Do not use Delo 400, it does not meet the sulphated ash spec.
Mobil Delvac 1240 SAE40
Chevron/Texaco Ursa SAE40 Super Plus

There may be others out there that will work, contact your local oil suppliers until you find one that can supply an oil that meets the specs.

Hey Willie,

I'm not doubting your advice one bit, but I have to at least mention that in the earlier days when all we ran was Yamaha's over the road, Shell Rotella T 15/40 was a very prevalent motor oil as an up-and-coming multi-grade in that particular era. That stuff was abundant on the shelf of truck stops as well as at oil distributors in bulk.

I never lost an engine to it, but I almost blame it 100% for the demise of one of my 3406B's that never stayed between the frame rails long enough to get to like it due to major problems constantly.

I have an old Detroit man who's been inside many of 'em and still is today. His philosophy is simple; keep the oilpan full, and make sure it's clean...and don't worry about all the snakeoils and hype these mfg.'ers put out to scare us into using only their brands.

If viscosity and ash content and all the other facts and fictions are what concerns us, then just use Lucas Oil Stabilizer faithfully for reassurance. Filtration should be the number 1 concern for an engine of that era, above the debate on multi-grades vs. straight grade oils...just my .02, but I lived the dream as well, you might say.:beerc

 

[willie59]

Hey Willie, I'm not doubting your advice one bit,

No worries on my end LowBoy. I'm certainly not an expert on the subject. However, I have some personal experience (which could still be considered anecdotal) but it lead me to do a little research on the subject. I have seen a number of Detroit innards that suffered from the use of 15W/40 and high ash content oils. Two of note, one was a compressor we purchased with an 8V-71. I knew nothing about its history, but it smoked like crazy when running and slobbered excessively. Thinking previous owner may have been using 15W/40, changed oil to Delo 100 SAE40, run the dog snot out of it, changed oil a couple more times, engine started better, less smoke, and less slobber from air box drains. The second was a Trackmobile, one of those rail car tuggers, with a 4-53. They called me because of hard starting, lot of smoke, and low power, oh and oil pouring from the air box drains. Turns out that engine was worn slap out. It operated in a fairly clean environment (on rail tracks) not much dust, and they had been using 15W/40. Pulled its innards out in the field, pistons were badly scarred, you could actually see hot spots on piston skirts, rings were stuck from ash deposits, liners were toast. Did an in-frame, switched to Delo 100 SAE40, maintained the engine for another 3 years and it ran perfect.

I don't know if they're sitll around, but one outfit that posted a lot of info about Detroit engines was Tejas Coach. They worked with buses, like Silver Eagles, that used the DDC two stroke engines, have a lot of info posted at their website. At one point, for a comparative test, they switched oils in some of their units to 15W/40 and noticed increased oil consumption compared to SAE40 of proper spec.

Another source is Detroit Diesel Corp themselves. Here's a paragraph from DDC publication 6SA314 8901:

Multi-Vis Oils

Less than optimum engine life must be expected when using 15w-40 oils.
Multi-vis oils tend to break down due to mechanical and thermal stress which
results in a loss of viscosity and premature engine wear. Multi-vis oils do
help cranking when temperatures are below 32 degrees F (0 degrees C).
However, once the engine starts, the major advantage of the multi-vis oils
is exhausted. When the engine reaches operating temperature, the internal
engine temperatures and pressures vary little from an engine operating in
much warmer climates. This is when the 2 cycle engine benefits from the
superior protection of a 40 wt.

Starting aids such as automatic ether systems and /or on-board auxiliary
heaters provide more reliable starting without sacrificing engine life.

Again, I don't claim to be an authority on this subject, it's just there's a lot of info out there that indicates multi-vis (15W/40) is not good for these engines. Given what it cost to rebuild an engine, hardly seems worth it to not give some consideration for the experience of others and the recommendations of DDC themselves. :yup

 

[LowBoy]

I can't argue with any of the information provided there willie. I guess it's just us guys up here in cold country that have the mentality that multi-vis. oils are "better" in cold climates, as I've had a few incidents in my lifetime that convinced us to switch.

Once I had to do a New Years Eve day run to Long Island, NY (ooooof, I'm having a bad flashback,) and it was -20F for a week. Had an old R-700 Mack with an 8V71, with 30W oil in the pan. The block heater was burnt out, so that was issue number one. Anyway, I started trying to light that thing up at 3 am to beat the traffic associated with I-95 and the "city".
With a battery charger AND a pickup on the batteries, that old 2 stoke turned like it was full of peanut butter. Later on, I had the charger, the pickup, a salamander heater pointing towards the batteries, and finally a wood fire going on a garbage can top under the oil pan, (grease caught on fire once, that's another story,) and a tarp over the motor...at 11 am she finally lit up. Got the run done...all good. Came in and switched to 15/40 for that reason, and it solved the hard cranking issue, so we just determined that multi-vis. oil was indeed a way to eliminate a lot of emotional stress.

I can't and won't dis the information provided by those credible publishers at all just because we had different experiences. Sounds like you've had good luck on your end making the switch to straight grade oil, so that's proof enough for me as well.:thumbsu

 

[willie59]

Cheers LowBoy. :beerc

 

[C R A F T]

Ever since this thread got started i've been racking my brain as to what kinda Oil grade I was using ..?????? …….. so long ago since I drove that 475hp silver Honda ????? …… but the more I think about it, it was 15/40w Delo 100 …. we could NEVER take the chance of using a straight 30 or 40w when we were logging and no readily available power to plug in the trucks for any length of time due to only having generators for power in the camps …. we did 250hr oil changes, any longer and the consumption went thru the roof. At 250 it would only be down a couple of quarts, which was bugger-all in a 40 qt pan.
We still used a 15/40w but it became the Delo 400 when we went to a Cummins, Cat or even the Big Mack V-8's ……. it's funny tho how if we switched (back then) say to Shell Rotella how oil usage was higher …. sometimes 1-2qts a week, we put on usually 5-600 hard bush/gravel miles a day … a very long day … LOL …. from crawling to full out highway speeds, off highway 60's and highway legal 53 metric tonne loads …… the picture i'm trying to paint here is the rigs were working hard all the time (no babying them) ……

I just wish I could get my negative film scanner to work on this new computer …. i'd love to post some pics …. but I won't give up on it , i'm trying to get a newer version driver for it down loaded …….. Cheers !!

 

[Longhood]

I have a friend who builds and parts out 2 stroke jokes, he said that he can tell if they have had multigrade oil run in them much, he says it also shows extra wear in the rack linkage especially if the multigrade gets run over the Detroit recommended 1/2 service interval (when compared to straight grade low ash)

 

[willie59]

I have a friend who builds and parts out 2 stroke jokes, he said that he can tell if they have had multigrade oil run in them much, he says it also shows extra wear in the rack linkage especially if the multigrade gets run over the Detroit recommended 1/2 service interval (when compared to straight grade low ash)

It's crazy to think these engines are so picky about the oil one uses in them, but in real life reality they are.

 

[Longhood]

It's crazy to think these engines are so picky about the oil one uses in them, but in real life reality they are.

A customer of mine had an engines life shortened by 15/40 use, he was assured by the suppliers rep that their oil met the spec for the 2 stroke, I questioned that and talked to the rep, turned out that another rep further up the chain decided that since the specs for lubricity etc were so close that it was OK. I did further research and from what I could figure out 1/2 service intervals would help slow the damage, but it was not recommended unless there was no other option, and with the lower zinc levels in the multi grades beyond CF, it is probably even worse now.

 

[RonG]

I just wish I could get my negative film scanner to work on this new computer …. i'd love to post some pics …. but I won't give up on it , i'm trying to get a newer version driver for it down loaded …….. Cheers !!

If it is a software problem try Vuescan.
http://www.hamrick.com/

 

[Truck Shop]

I know of one person years ago that ran nothing but Detroit 2 strokes. No joke the pan plugs never came out unless there was engine work to be done.
He changed filters only. He had several silvers run 800K and no oil changes. Those engines were designed to use a gallon every 2500 to 3000 miles.
He just added oil. And ran nothing but 40wt. I tore one of those engines down at 788k that was the filthiest thing I ever worked on. And unlike some
owners he ran those silvers right up on the governor.

Truck Shop

 

[Longhood]

I shudder every time I here about those won't change the oil guys, I have cleaned out the spinner filters on enough old macks to know what collects on long run oil. I doubt if he saved a whole lot of money, broken down oil leaves the pan quicker than clean oil.

 

[Truck Shop]

I shudder every time I here about those won't change the oil guys, I have cleaned out the spinner filters on enough old macks to know what collects on long run oil. I doubt if he saved a whole lot of money, broken down oil leaves the pan quicker than clean oil.

Well with 10x30 synthetic being the rave now everyone is going to 30,000 mile intervals on oil changes, Three oil changes in 100,000 miles.

 

[Longhood]

There is a pretty big difference in today's engine technology compared to a fixed timing oil cooled bottom end 2 stroke.
I recall back in the 1980s, we serviced a fleet of Macks that ran amsoil, they got 3 changes in 60,000 miles, 50,000 or better on 1 change of Amsoil, a really short change with Cheaps 15 w40 and a quart of a detergent additive that they supplied, then a 5000 mile run of rotella T before going back to the Amsoil, Those trucks got good engine life, as good or better than the regular interval dino oiled trucks, but who knows if they saved money, I hated doing overheads on them, the rocker covers were coated with grimy sludge on the inside. Of course 350 Macks put a lot more crap in the oil than a modern non EGR engine.

 

[Truck Shop]

There is a pretty big difference in today's engine technology compared to a fixed timing oil cooled bottom end 2 stroke.
I recall back in the 1980s, we serviced a fleet of Macks that ran amsoil, they got 3 changes in 60,000 miles, 50,000 or better on 1 change of Amsoil, a really short change with Cheaps 15 w40 and a quart of a detergent additive that they supplied, then a 5000 mile run of rotella T before going back to the Amsoil, Those trucks got good engine life, as good or better than the regular interval dino oiled trucks, but who knows if they saved money, I hated doing overheads on them, the rocker covers were coated with grimy sludge on the inside. Of course 350 Macks put a lot more crap in the oil than a modern non EGR engine.

I totally agree the oils today are far better than any time in the past. But one problem it has created { Fleet owners, managers and dispatchers think today's oil change intervals
means you can over run service's on mileage}. It's wonder oil in their mind. It's happened at my place of work and I know others with the same problem. Oil sampling is just a
guide to go by. Good maintenance is still the key to a good operation. It's desk top trucking, and only getting worse.

 

[rzucker]

I will say this much. Had a customer with a bunch of 12V71Ts in scrapers and they were running 15/40 and using 1.5 gallons of oil per engine per shift. I suggested going to straight 40wt in the hot months ans 30wt in winter. Cut his oil comsumption by a gallon per engine per shift and the airbox drains quit dribbling oil. Multiweight oil does not work in 2 stroke Detriots, Period. If you actually read the lube oil recommendations in the service manual it will state that.

 

[soperlogan]

Has anyone tried synthetic oils? Rotella T-6 low ash and high zinc and extremely low viscosity sheer. Here in northern New England we use it on skidders down to15 below. In woods operations there is no such thing as starting aids. If anyone thinks they are going to start a 3-53 on straight 30 weight here in winter they are dreaming. You couldn't lug enough batteries to a machine to turn it over.
Maybe I'm wrong

 

[Longhood]

is the T-6 designed for the 2 strokes or is it just closer to the spec than other multi grades??
the properties you described would help. I have heard stories of old loggers dumping a couple of quarts of gasoline into the engine after letting it cool off, at the end of the day, according to legend, they would shut the machine down while they greased it and did their other service, then they would add the gas and fire it up for long enough to mix the gas into the oil. In the morning they would fire them up and be careful not to load them up much until they thought most of the gas had evaporated. Synthetic T-6 sounds safer and easier.

 

[soperlogan]

Lot closer to specs It's actually a 5w40 I don't know we only operate in winter so its all we use. I know it starts good on cold mornings Find out down the road if it helps or hurts.