Engine/Transmission (1994 - 1998) Oil for Turbo Diesel

[Elite1]

I have read several threads on TDR saying not to use Mobil1 oil. Just wondering why not? I have used it for years on gas engines, with great results. On the bottle of Mobil1 it says it is for use with gas,diesel, and turbo charged engines. The Mercedes Turbo-Diesels come with Mobil1 from the factory, and they recommend it.

That being said, I have always used Rotella dino oil, on my 96' Dodge Turbo Cummins with 156,000 mi... . but am considering switching to a synthetic. I notice there is a full synthetic Mobile/Delvac1 which is a heavy duty diesel oil which comes in a 15-40 wt. and is rated at ch4 and ci4.

Any thoughts to these two synthetics and where Delvac is available, I'm in Ventura County, Calif. Thanks, Marty

 

[grtescpa]

Originally posted by Elitel

I have read several threads on TDR saying not to use Mobil1 oil. Just wondering why not? I have used it for years on gas engines, with great results. On the bottle of Mobil1 it says it is for use with gas,diesel, and turbo charged engines. The Mercedes Turbo-Diesels come with Mobil1 from the factory, and they recommend it.

That being said, I have always used Rotella dino oil, on my 96' Dodge Turbo Cummins with 156,000 mi... . but am considering switching to a synthetic. I notice there is a full synthetic Mobile/Delvac1 which is a heavy duty diesel oil which comes in a 15-40 wt. and is rated at ch4 and ci4.

Any thoughts to these two synthetics and where Delvac is available, I'm in Ventura County, Calif. Thanks, Marty

Try Amsoil. They are the original people in the synthetic oil manufacturers. It won't stink like Rotella when its first changed.

 

[redram]

Mobil 1 is not the correct API ratings for the Cummins B Series engine. If you like the Mobil brand, the correct Mobil product to use in their synthetic line is the Delvac 1.



Cummins recommends a 15W40 viscosity grade oil having an API rating of CH-4 / SJ minimum. Use a synthetic that meets these requirements as stated in your Owners manual or Service manual.



You can check out if an oil is rated for these and licensed by the APi by checking out www.api.org under the consumer section. API is the American Petroleum Institute and serves as the watch dog for the consumer on sub-standard oils in their Engine Oil Licensing Certification System (EOLCS). They actually go out and purchase oil at consumer stores and have the oils checked by labs to make sure that the oils meet the API standards such as viscosity grade, proper additive treat levels, etc.



I have run Royal Purple 15W40 now for 10+ years in my two Cummins with over 315,000 + miles of trouble free service. I change the oil at 12,000 intervals and have run the Fleetguard filters at 4000 to 6000 mile intervals with excellent results.



Good luck.

 

[C Schomer]

Mine is doing great with RP 15w40 also. I do analysis and change the full flow filter every 5k. I have an Oilguard bypass - soot stays at . 1, sample after sample after sample. I don't know how long the bypass filter will go. I'm thinking about 25k. It's still doing a good job after 15k. Fresh oil in the filter and makeup are keeping the TBN at 10 and the oil chemistry looking like nearly new oil. I know you can do cheap changes if you buy oil at Costco or Sams but I like doing analysis and would rather not change good oil without knowing. Craig

 

[mmayron]

Originally posted by C Schomer

I have an Oilguard bypass.

Sorry if this is a dumb question and it's been answered a billion times before but what are the benifits to using this and is there really a need unless you do major towing? I just bought a 97 w/ 170k miles on it and would like to keep it running as long as posible. The prevous (and only) owner said he used rotilla oil and changed it every 3 or 4 thousand miles but I'd have to say i'm synthetic man and will be switching for the next change. Is this something I might want to consider installing aswell? I'll hardly ever tow anything except for the ocasional car but will probably be stuck in Southern california traffic/heat soon and I know it's really hard on engines. Would this type of setup offer any benifits in my situation?

 

[illflem]

mmayron, I don't want to start any arguments here but I'd be apprehensive about changing to synthetic so late in the game (170k). You are very likely to spring some leaks afterwards.

 

[mmayron]

Is that because the synthetic is able to work it's way through seals on account of it having smaller molecules? If it did leak a bunch could I not just switch back to dino juice? I know it's not a problem w/ gassers but I'm new to the whole diesel thing.



Thanks for the input though,



-Mike Mayron

 

[C Schomer]

You can always get benefit from a bypass. Oilguard says it's plenty safe to double your change frequency, just by adding their bypass - with ANY oil. I think it was Frantz that claimed a gasser could go indefinitly with their filter. It wouldn't surprise me after what I'm seeing with mine - full flow changes and makeup are keeping the oil nearly like new - even in a diesel. Bypass filters REALLY complement an extended change and analysis program - that's why I did it. I take some serious milage vacations in the summer. I almost got a Frantz but Oilguard went on sale when I was ready to buy. The Frantz does a darn good job, if you want to save some $$. Dad used them in the 60s on his trucks. They kept the oil somewhat brown instead of turning black. I think someone on this site sells them cheap. Craig

 

[redram]

Do you have proof of this or is this an old rumor?

Originally posted by illflem

mmayron, I don't want to start any arguments here but I'd be apprehensive about changing to synthetic so late in the game (170k). You are very likely to spring some leaks afterwards.

They is very little chance of a leak developing in an engine that is mechanically sound. Using a better quality oil will always be the best option and if you feel / believe that a synthetic is the way to go, do it.



Now, if the used engine already leaks alittle oil, changing to the synthetic oils, which are more uniform in molecular size and have better solvency than the mineral oils, they will try to "clean up" existing deposits left by the mineral oil (Delo, Rotella, Delvac) that might be plugging some of the leaks in the marginal seals.



On a 12 valve like the 97, buy a set of new valve cover gaskets for $15 bucks, clean up the top end of the motor, adjust your valves, and put on the gaskets and fill with the higher performing oil. If it's a rear main seal, it would not be recommended to switch to the higher cost oil until you fix the "mechanical problem" (possibly caused by the cheaper mineral oil leaving some deposits on the seal which leads to hot spots which cooks the elastomer, which results in a crack and a leak. )



Synthetic oils will not CAUSE oil leaks but they sure as well will find any MARGINAL or MECHANICALLY Unsound gaskets and will leak.



Of course, they also lubricate better and provide improved performance, measured in horsepower, torque, fuel mileage, lower operating temperatures, better corrosion protection, superior anti-foaming, and higher and lower temperature ranges and superior oxidation resistance.



Other than that, they don't do much... .



Illfem, please don't take offense, I'm not picking on you.....





Yes, I use synthetics.

 

[LarryB]

With 6K+ posts I'd bet that illflem has seen a few discussions on oil. Dont take his advise lightly.

 

[CumminsPower98]

I second LarryB and agree with ifflem, definitely something to consider. I got my truck with 67k on the clock and a few months later I put Amsoil Series 2000 75w90 gear lube in the NV4500. I'm not sure at what mileage this was but I now have 91K+ so it was some place between there. Anyway, a while after installing the Amsoil I noticed a slight dampness at the bell housing. There was just enough there I could get a little on my finger to tell me it was gear lube coming from the front trany seal. Well that went on for a while but never got bad enough to make a spot where I park. Time passed and next thing I knew it was not leaking anymore so I cleaned there area really well and it's been dry ever since. A similar thing happened to the front output seal of the t-case.



Mark

 

[Pit Bull]

Re: Re: Oil for Turbo Diesel

Originally posted by grtescpa



It won't stink like Rotella when its first changed.

STINK, them are fightin words :-laf

 

[redram]

Originally posted by LarryB

With 6K+ posts I'd bet that illflem has seen a few discussions on oil. Dont take his advise lightly.

The "number of posts" that a member chooses to respond to has no relevance to the accuracy of those posts. I happen to have 20+ years of experience using industrial and automotive synthetic products and pay my bills being the Technical Services Manager for a major independent manufacturer of lubricants. I also am a degreed Mechancial Engineer and am certified by the STLE (Society of Tribologist and Lubrication Engineers) as an Oil Monitoring Analyst and Lubrication Specialist. I also do my own maintenance as well as build race cars. I feel I was qualified to post a contary post to one that I felt was not entirely accurate.



I just get tired of people making blanket statements about subjects that are just not true and cause mis-information to be spread around forums like this.



Leaks can develop in older vehicles if someone using a high detergent mineral oil or decides to flush an engine or just changes the loading pattern of the equipment.

Heck, on my 89 Dodge (yes, I've owned Cummins powered vehicles for 12 years) I had two axles seals leak in the first 70,000 and it was using the original fluid. Switched to a synthetic, and never had another one leak over the next 100,000 when I sold it. On my new truck (96) I'm on the original axle seals after 7 years with synthetic on my current truck and no leaks.



I thought I was adding both professional knowledge and a long history with the Cummins / Dodge when I made my comments. Whether I've chosen to post 10 times or 10,000 times might be a reflection of how much free time I have to post!



Sorry, Had to vent alittle.

 

[Dull Pain]

oil

Now boys :-{}



Gotta go with redram on this one. He makes sense!



No disrespect to illflem or anybody else.

 

[illflem]

Redram, in your first post you basically say the same thing I do, just use a too many extra words like an engineer. My only recommendation was to give the possibility of leaks a thought. I'm sure you would have to agree his chances of developing leaks after a change to syn are greater than the chances if he just continues with his present oil and especally increases with the mileage on the engine. In my opinion the risk of leaks far outweighs the added benefit of synthetic. I agree it's not the syn oil that causes the leaks, it just opens them up.

 

[Pit Bull]

What do you'all think? I now use Rotella T 15w40 every 6K miles with Standard Mopar filter. 55K miles on truck, thinking about changing to Delvac 1 synthetic and changing ever 8K miles with Microglass filter. Is it worth the extra money? I alway plug it in when it gets below 40 degrees in the winter. Most of my mileage is highway 55 - 60 mph. Thanks

 

[Champane Flight]

Agree

I do agree with almost everything said here. As far as going to synthetic after 55 thou, go ahead you can't hurt anything. I went to Amzoil after 10 thou and have never been sorry. I do not have a bypass filter (yet) and go 12000 between changes 6000 between filters. I have not had any abnormal reading from analyizing. I gained about 1mpg after going all synthetic, all gears.



My transmission started to seep out the tail shaft seal right after going to synthetic. I found that the oil level was a touch high, opened the side filler plug and let it drain down, and it was OK from then on. I have found over the years that oil seeps on an diesel engine are a norm and not something to be afraid of. As my ole Dad used to say "At least you know the bearing in front of the seal is getting lubrication. " Keep your eye on the seeps if they grow into full fleged leaks, then it is time to do something.



Redram is correct and so is Ill. I have owned diesels and been around about every model, size, and type of engine out there, they have ALL had a seep or two. Some just outright leaked (see Jimmy Vs). Good luck with your choice Pitbull. I favor Amzoil, but there are many excellent oils out there. Check the internet for the many brands and a dealer near you.

 

[Pit Bull]

Re: Agree

Originally posted by Champane Flight



Good luck with your choice Pitbull. I favor Amzoil, but there are many excellent oils out there. Check the internet for the many brands and a dealer near you.

Picked Delvac synthetic because it is sold at a truck stop near me. Plus everyone has said it is a good oil???

 

[Elite1]

Re: Agree

Originally posted by Champane Flight

I do agree with almost everything said here. As far as going to synthetic after 55 thou, go ahead you can't hurt anything. I went to Amzoil after 10 thou and have never been sorry. I do not have a bypass filter (yet) and go 12000 between changes 6000 between filters. I have not had any abnormal reading from analyizing. I gained about 1mpg after going all synthetic, all gears.



My transmission started to seep out the tail shaft seal right after going to synthetic. I found that the oil level was a touch high, opened the side filler plug and let it drain down, and it was OK from then on. I have found over the years that oil seeps on an diesel engine are a norm and not something to be afraid of. As my ole Dad used to say "At least you know the bearing in front of the seal is getting lubrication. " Keep your eye on the seeps if they grow into full fleged leaks, then it is time to do something.



Redram is correct and so is Ill. I have owned diesels and been around about every model, size, and type of engine out there, they have ALL had a seep or two. Some just outright leaked (see Jimmy Vs). Good luck with your choice Pitbull. I favor Amzoil, but there are many excellent oils out there. Check the internet for the many brands and a dealer near you.

I have selected Delvac1, full synthetic... I am waiting for a new oil plug back ordered from Geno's, before I install my new oil. You say you change your filter @ 6000 mi. , and oil @1200. Do you prime your new filter with oil? You also said "side filler plug" do you have a manual or auto transmission?

 

['956Wheel]

DELO! Or you can buy the oil that will do everything, I think you can fry fish in it too! :--)



Mike