I'd have no concern using it in the summer in such a vehicle, which, in your case, is year round.
15w40 conventional turbo coking??
- Thread starter Ponch
- Start date
- Status
Hi,
Ponch - Mineral HDEOs of 15W-40 viscosity are probably the standard in most of the World in OTR operations
I have seen many instances of "coking" and "sludging" in heavy high speed diesel engines. They have typically been related to end user issues or the use of a non conforming/compliant lubricant in particular engine families. This has not been common IMO over the last decade or so with the progressive upgrading of HDEO's compliance via OEMs, the API and ACEA Standards and Warranty requirements
Ponch - Mineral HDEOs of 15W-40 viscosity are probably the standard in most of the World in OTR operations
I have seen many instances of "coking" and "sludging" in heavy high speed diesel engines. They have typically been related to end user issues or the use of a non conforming/compliant lubricant in particular engine families. This has not been common IMO over the last decade or so with the progressive upgrading of HDEO's compliance via OEMs, the API and ACEA Standards and Warranty requirements
wemay
Site Donor 2023
Originally Posted By: Garak
I'd have no concern using it in the summer in such a vehicle, which, in your case, is year round.
Thank you Garak.
I almost forgot, you use Delvac in your G37.
I'd have no concern using it in the summer in such a vehicle, which, in your case, is year round.
Thank you Garak.
The old Audi allowed for 15w-40 down to something like -15 or -20 C. I ran it in the summer, but I didn't take it down to much below freezing. When winter hits, it doesn't mess around here, so I waste no time.
Originally Posted By: JHZR2
OTR diesels may be significantly different in turbo and lube design than consumer vehicles. I also doubt that OTR truckers instantly turn their engines off after slamming on the brake off an interstate offramp from an 80 MPH cruise.
I am not sure I have ever seen anyone with a diesel pickup or car just run down a off ramp and turn the key off either. A turbo cools down quite a bit just the coasting down the ramp and then driving down the street a ways and then to a stop. I have no problem taking my semi truck off the interstate under full load, down the ramp, to a stop, then down the street a little bit, into a truck stop lot, up to the fuel pump and turning the motor off. No serious cool down idling time. Took my 1996 Cummins N-14 to 1.4 million miles on conventional Kendall 15w40 without a turbo replacement. My 2006 Cummins ISX, I took to 968,000 on Allied 15w40 (a regional oil supplier label). It did need a new VG turbo at just over 800,000, but that centered around the actuator and not the turbo shaft or bearings that are directly involved with the oil.
The key is to have a pyrometer and take all the guessing out of the process. The design between the auto / pickup diesels and the commercial heavy trucks is strikingly similar.
OTR diesels may be significantly different in turbo and lube design than consumer vehicles. I also doubt that OTR truckers instantly turn their engines off after slamming on the brake off an interstate offramp from an 80 MPH cruise.
I am not sure I have ever seen anyone with a diesel pickup or car just run down a off ramp and turn the key off either. A turbo cools down quite a bit just the coasting down the ramp and then driving down the street a ways and then to a stop. I have no problem taking my semi truck off the interstate under full load, down the ramp, to a stop, then down the street a little bit, into a truck stop lot, up to the fuel pump and turning the motor off. No serious cool down idling time. Took my 1996 Cummins N-14 to 1.4 million miles on conventional Kendall 15w40 without a turbo replacement. My 2006 Cummins ISX, I took to 968,000 on Allied 15w40 (a regional oil supplier label). It did need a new VG turbo at just over 800,000, but that centered around the actuator and not the turbo shaft or bearings that are directly involved with the oil.
The key is to have a pyrometer and take all the guessing out of the process. The design between the auto / pickup diesels and the commercial heavy trucks is strikingly similar.
Only turbo I've seen coked was one of our skid steers, had to do a little training with the guys using it (about 60 of them with high turnover of employees) because they had a habit of going from cold start to WOT and full load with no warm up and from full load WOT to off with no cool down. Neither were good for the turbo and we went through a few of them before they finally got with the program. Took me almost 2 years to get everyone to start treating the equipment right.
Originally Posted By: ironman_gq
Only turbo I've seen coked was one of our skid steers, had to do a little training with the guys using it (about 60 of them with high turnover of employees) because they had a habit of going from cold start to WOT and full load with no warm up and from full load WOT to off with no cool down. Neither were good for the turbo and we went through a few of them before they finally got with the program. Took me almost 2 years to get everyone to start treating the equipment right.
Turbocharged Kubota by chance?..just curious..
Only turbo I've seen coked was one of our skid steers, had to do a little training with the guys using it (about 60 of them with high turnover of employees) because they had a habit of going from cold start to WOT and full load with no warm up and from full load WOT to off with no cool down. Neither were good for the turbo and we went through a few of them before they finally got with the program. Took me almost 2 years to get everyone to start treating the equipment right.
Turbocharged Kubota by chance?..just curious..
Originally Posted By: daman
Our OTR trucks and heavy equipment ALWAYS gets a cool down period after hard use,gets ya fired if you don't!
There is your oil coking problem OP. The easiest way to coke or burn up a turbo is when the exhaust side is 1000 degrees and the oil side is 260 degrees. Ive always tried to get the EGT down to about 300 before shutting it down.
Our OTR trucks and heavy equipment ALWAYS gets a cool down period after hard use,gets ya fired if you don't!
There is your oil coking problem OP. The easiest way to coke or burn up a turbo is when the exhaust side is 1000 degrees and the oil side is 260 degrees. Ive always tried to get the EGT down to about 300 before shutting it down.
and 1000°F is peanuts... 1500°F is were my car starts limiting power output...
EGTs are probably not a very good piece of data for coking at shutdown. If you run 30 minutes at 1200, let off the accelerator, your EGTs should drop in several seconds (mine go to 275-300 or so). The bearing on the turbine side is still going to be way hotter than that.
Well, no serious cool down procedures followed, and I took a Cummins N-14 to 1.4 million miles without a turbo change out. Same for a Cummins ISX with a VG turbo to 968,000 miles. Usually by the time it goes from working a higher EGT's, down an off ramp, down the street a ways to a parking area, and the turbo has sufficiently cooled. I suppose that those who like to lay on full boost and get EGT's to 1200 and then shut the motor off might have problems. Oh, 2006 Jeep Liberty Diesel, I took it to over 115K and then my son took it over. Still has not had any turbo problems with the Garrett VG turbo on it and same philosophy applied as with my heavy diesels.
Hi,
951Indy - The transition from one operating temperature point to another is typically quite fast
The DD Series 60 engines I operated had these points;
Shut down = 576C/1100F
Warning = 437/820F
Normal = 350C/700F
In operation these temps were recorded;
Highest 425C (climbing)
Lowest 300C (flat)
Excessive idling can be a real cause of turbo failure as can be the actual position of the turbocharger on the engine. High mounted turbos (example; some early Cummins applications) tend to lose oil flow very quickly on shut down and this can causing impellor shaft/bearing issues if shut down quickly say after a long climb under heavy load. Modern lubricants are now certainly much more robust in these areas
I never experienced any turbo problems on my own vehicles. On project/research work I saw many instances - typically traceable back to the use of incorrect lubricants or operator "issues"
951Indy - The transition from one operating temperature point to another is typically quite fast
The DD Series 60 engines I operated had these points;
Shut down = 576C/1100F
Warning = 437/820F
Normal = 350C/700F
In operation these temps were recorded;
Highest 425C (climbing)
Lowest 300C (flat)
Excessive idling can be a real cause of turbo failure as can be the actual position of the turbocharger on the engine. High mounted turbos (example; some early Cummins applications) tend to lose oil flow very quickly on shut down and this can causing impellor shaft/bearing issues if shut down quickly say after a long climb under heavy load. Modern lubricants are now certainly much more robust in these areas
I never experienced any turbo problems on my own vehicles. On project/research work I saw many instances - typically traceable back to the use of incorrect lubricants or operator "issues"
I met some guys who had turbo problems with their Ford 6.0 PSD, but I don't know if it is because the oil cant take the turbo temperature, or if it is because the Ford 6.0 PSD was a problematic engine.
I did advise those guys to use full synthetic and allow the engine to idle 2 minutes before shutdown, but I don't know if it would have solved the problem for the 6.0 PSD.
Also, I hear of turbo failures on certain DPF equipped engines. Is it because the EGT must get hot to regenerate the DPF? If that is the case, I think using a full syn might solve it. The VW 2.0 CRD appears to work well, and it uses only synthetic oil.
I did advise those guys to use full synthetic and allow the engine to idle 2 minutes before shutdown, but I don't know if it would have solved the problem for the 6.0 PSD.
Also, I hear of turbo failures on certain DPF equipped engines. Is it because the EGT must get hot to regenerate the DPF? If that is the case, I think using a full syn might solve it. The VW 2.0 CRD appears to work well, and it uses only synthetic oil.
Heck, I even use turbo blankets on my turbos and don't do anything different that I have before. No extended turbo cool down thing. I just watch the pyrometer and when it drops to within 300F, which is most likely by the time I coast to a off ramp, go down it, turn and go down the street a a block or two to a parking area. Matter of fact, using turbo blankets, my EGT's under load are even cooler than not using one. Even on a hard pull, long grade, on a hot day, my EGT's never go above 900F. Detroit Series 60 515 hp 1750 torque.
The OP's in Michigan. I'd be more concerned about cold starts with 15w-40 instead of synthetic 5w-40 in a diesel. My real world experience includes a cold starting my 6.0 PSD after an eight hour cold soak at -20F simultaneously with an identical 6.0 parked next to mine. Neither truck had its block heater plugged in.
Mine started after a cranking twice as long as during the summer, experienced some rough running for about ten seconds an d settled into a normal idle. The truck in the adjacient parking spot cranked several times totaling more than a minute and then bucked like crazy for at least two minutes before settling down. The driver actually came over to me as hour trucks were warming up to ask how I got mine to start and run so easily.
I cannot believe how many truck owners run 15w-40 in cold climates.
I was super careful with my completely stock 6.0 PSD. Only Delvac 5w-40 and no short trips and careful cool downs. Nothing helped except selling it.
Mine started after a cranking twice as long as during the summer, experienced some rough running for about ten seconds an d settled into a normal idle. The truck in the adjacient parking spot cranked several times totaling more than a minute and then bucked like crazy for at least two minutes before settling down. The driver actually came over to me as hour trucks were warming up to ask how I got mine to start and run so easily.
I cannot believe how many truck owners run 15w-40 in cold climates.
I was super careful with my completely stock 6.0 PSD. Only Delvac 5w-40 and no short trips and careful cool downs. Nothing helped except selling it.
Last edited:
Well, some of us, especially in the northern tier, use oil pan heaters that have the 15w40 flowing at start up like a warm summer day.
Originally Posted By: TiredTrucker
Well, some of us, especially in the northern tier, use oil pan heaters that have the 15w40 flowing at start up like a warm summer day.
That's great if you can plug in where you park or keep the engine running until you get to where you can park.
Well, some of us, especially in the northern tier, use oil pan heaters that have the 15w40 flowing at start up like a warm summer day.
That's great if you can plug in where you park or keep the engine running until you get to where you can park.
- Status
Similar threads
- Sticky
