My last sample came back with 5% fuel in the oil. I dropped the truck off for possible leaking injectors at the dealer. After a day the service advisor calls me and says that they checked with Chrysler and 5% isn't bad for my engine. He said it's normal because the high compression engine will cause some blow-by.

The oil was ran a little over 7.5K miles and my truck had about 70,000 on it when I sampled. I have about 6,500 miles on this oil so I figure I'll sample again and see what % I have now. I think the dealer is just trying to get out of the warranty work because my warranty is close to gone, and they figure I won't have an issue until it's too late for warranty work.

Any opinions?

 

Do you let it warm up any before getting on it in the morning.When a diesel is cold all the fuel doesn't get burned,a little goes in the pan, and some out the pipe.

 

in the navy we'd allow 7% on the diesels. i would keep a very close eye on it for a while. it may be your driving habits. if you do alot of short trips that never fully warm it up, you'll get some fuel dilution. load that baby up and go for a good long hard pull. then check. probably be better.

 

5% seems high, i send my oil in every change in all my trucks and have never had 5%...mabe 1 or 2%, keep in mind driving times and usage will play a small roll but if you drive mostly long trips 25-30+mi 5% seems kinda high. Keep an eye on your oil levels. Dodge has no idea what is going on so totally discount whatever they say, maybe even do the opposite, remember the only way they make money is when you buy a new truck!!!

 

summer time driving you should have very little if any fuel in the engine oil. My last sample at over 10,000 miles on it didnt have any fuel in it.

 

Normally I drive my truck twice a week...To my office on Monday and to my house on Friday and the trip is 18 miles, stop and go each way. I try **** hard to keep the RPM's under 1800 or less until the engine reaches operating temperature. On some weekends I tow offroad toys around 180-250 miles to various places. I'm not easy on my truck by any means once shes warmed up though. I'll keep an eye on the fuel levels in the oil and if I think there's a problem, I'll just get some bigger sticks and a few more goodies and say "to hell with the warranty!" It is just about useless at this point anyway with just over 20K to go.

Thanks for the suggestions and replies.

 

So far, after 22k miles, my oil analysis shows <1% fuel contamination. Depending on the lab you use, will dictate how sensitive their equipment/analysis is. I'd have to say that <1% is probably a detectability limit by my labs' equipment.

As you probably already are...I'd be concerned with the 5% dilution. Basically, 5% of 3 gallons equates to 19.2 ounces of fuel in the oil. Or, ~1/2 qt of fuel.

I hate to say it, but the dealer may be right. Have you noticed the oil level increasing? Most injector failures are catastrophic and binary...they either work or they don't. You may have just found one that is marginal, and leaking by.

Or as someone mentioned, you are idling too much at low rpm. If this is a later model (04.5-07) you may be able to get the hi idle enable to keep combustion temps up and prevent the fuel dilution you are seeing....if that is indeed the problem.

HTH

Tony

 

My UOAs have all come back with zero diesel in the fuel. I have 115,000 miles on the engine. I have to admit I would be concerned about 5%, but am not knowledgeable enough on the subject to give you a good opinion. I would certainly want to know what is causing it.

 

Funny you should mention the high idle feature. I asked the service adviser how much they would charge me to turn it on and his response was it couldn't be done to my year model truck. I said 'ok, if you say so'. I left, went to my office, printed out the TSB, and stopped back by the dealer on the way home. I put the printout on his desk and after he read it, he said sure we can do that for $90 bucks. I love teaching people stuff they should already know

 

I sampled the oil today and I'll ship it off tomorrow. I'm using Blackstone for my lab. Hopefully there was just a silly issue with the last sample. If the new one comes back crappy, I'll take the truck and sample report back to the dealer just for giggles and see what they say. I'm sure they'll regurgitate the same old crap but I would at least like to see them do actual work on the truck this time to investigate the matter.

 

I'd at least have it documented. Even if you have to pay 1hr shop rate labor. If there is a failure in the future, you may be able to get your money back.

Tony

 

Just make sure the truck is stock and have them write down on the work order that they said that 5% was okay. That way if something does go wrong you can say that I brough the truck in with the problem of 5% and you did nothing...

Just make sure you have a writtne copy.

 

This was going to be my response but you beat me to it.
It will be interesting to see if the spuirm or not.

 

5% seems high to me. I work on large stationary engines and the antique out of date 6 1/4 bore Cats (pc engines) only produce 5%. They get over that, and there is a problem.
The newer 3500 (B and C) series engines produce VERY little fuel dilution, and these engines produce power in the 1000-3200 hp. range! You might try contacting a local Cummins service center and ask what they feel is an acceptable fuel dilution percentage. I'm sure Cummins actually has a spec. for this as most diesel engine maunfacturers do.
Automobile dealerships have no clue about oil sampling, lab testing, or translating oil sample data into making repairs. White out the notes and suggestions from your lab report and hand the raw data to the service advisor and see if he can see anything wrong.

 

I just got my report back on my 07 and there is <0.5% fuel dilution. It was always the same on my 97 also. Reports are from blackstone. I would press your dealer a little more or find a new one.
Will