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Detroit 6V92 100,000 Mile Oil Change

November 07, 2012, 09:34:54 pm

I found a tech piece from Detroit Diesel that indicates one needs to change the oil in our Detroit 6V92 every 100,000 miles. The section stating this in on the last page in the lower left hand corner of the attached pdf file. It states that the primary oil filter needs to be changed every 25,000 miles but the oil itself will last 100,000. I am interested in comments from those more knowledgeable than me about the 2 stroke Detroits.

I have run my 6V92 for 15 months and 13,000 miles without an oil change. I did however regularly send in oil samples every 3,000 miles to Blackwood Labs and was impressed that the oil analysis stated that the oil had not deteriorated at all in that period. I just changed the oil just because it seemed like the right thing to do but it was a pain and I would love to be able to only change the filter every two years.

So what do you think???

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Re: Detroit 6V92 100,000 Mile Oil Change

Reply #1 – November 07, 2012, 10:25:05 pm

Kent,
That is an interesting tid bit of info, wonder what year they printed that sheet.  I still feel the cheapest insurance is good oil and changing it.  I sure would not dispute DDC tech info, so I have to say WOW!.  Me I change when I feel like it, that ranges between 4-8 k miles in general.  Still love the ole DDC engines and miss them, love the sound and the older mechanical jobs can be setup to crazy HP output, 750 HP on a 8V-92 is easy, just 8 injectors, correct turbo, make or buy the heavy steel air box covers, the cast aluminum just break off due to air box pressure, SAE 50 oil and 2600 RPM, then smile... Longevity is not real long and difficult to properly cool.
The DDEC setup is not as easy nor cheap.
Cheers
Dave M

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Re: Detroit 6V92 100,000 Mile Oil Change

Reply #2 – November 07, 2012, 11:12:36 pm

For whatever it's worth... Leave a bottle of water or any liquid for that matter out in the open. See all that condensation? I have to believe that some variation of that goes on inside the oil pan/crank case of an engine just sitting still. Having said that I change my oil based on how much time my coach sits still. I used to be an over the road truck driver/owner operator. Having put over million miles on an old Peterbilt and having changed the oil countless times I can say that after 10K miles the oil gets visibly darker and starts to smell bad. If this doesn't mean anything I would be very surprised. I am for sure not an expert but I would never go more then 10k miles without changing my oil. Having spent as much as 9K to rebuild an engine or two the $200.00 for an oil change seems like cheap insurance

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Re: Detroit 6V92 100,000 Mile Oil Change

Reply #3 – November 08, 2012, 12:06:17 am

I can see a truck or bus engine with few cold starts getting pretty long life from oil. I know some operators used bypass filters when they extended oil changes. Not being an oil expert, I can't intelligently comment on a 100K interval. We were told that sulphur in diesel fuel accelerated engine wear but don't know if it was a wife's tale. I do know that we changed oil every thousand miles as the taxpayer was paying the bill. 100,000 miles does seem like a long time. I don't like going over a year between changes even if I don't put many miles on an engine. An old habit I guess. Your lab work may indicate otherwise. Have been averaging about 10K a year so it works out.

Interesting DD advertisement for the "fuel squeezer". We blew up a gas engine in an almost new American La France. Rather than take a chance on another gas engine, we started replacing the gas engines with 8V-71s. Excellent conversions until we tried replacing the 590 Hall Scotts in the Crowns with a 6-71T they called a fuel squeezer, the only Detroit that would fit in that application. The factory had the supercharger geared slower than normal and mounted a turbo to boost the power to almost 8V-71 levels. The problem was the 4 speed manual had big gaps between gears plus the fuel squeezer had a REALLY narrow power band so we had to wait for the boost to build, accelerate and then try and make a good shift with the crash box Spicer transmission. Was the only rig I really hated to drive.

Pierce

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