Any of the modern 5w40 diesel oils will work far better than 15w40. More so as it gets colder!
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Mercedes 240D - Mobil 1 Turbo Diesel Truck?
- Thread starter 83benz
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For the past fifteen years all I've used in my 240D and 300SD is Mobil Delvac 1 I pick up at the Farm & Fleet. The 240D will use some oil, a quart very two thousand, if I do a lot of highway miles. Highway miles usually mean flat out, 75 mph or so. I remember back on the old MBA.org forum that Delvac1 was recommended due to its ability to hold soot/ash, which was what sold me. Somewhere I have some old Blackstone results from 7.5k intervals for both vehicles that could have gone to 10k. For me the Delvac1 is cheap insurance to keep these things going forever. What really helped me in the cold was converting the 240D from the old toaster wire series glow plugs to the 1980's tech parallel glow plugs.
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Originally Posted By: JHZR2
Besides easier starting, studies a while back indicated about 1/2 the rate of timing chain "stretch" (wear) when synthetics were utilized.
...And less chain guide wear with syn. I remember that info as well.
5w40 T6 is in my '82 240d...
Besides easier starting, studies a while back indicated about 1/2 the rate of timing chain "stretch" (wear) when synthetics were utilized.
...And less chain guide wear with syn. I remember that info as well.
5w40 T6 is in my '82 240d...
lol, my 240, which has 73k and is like new, shakes far more, and is noisier than any 617.952 equipped car that I have owned. The 300D cars also have more sound deadening, IIRC. And on the highway, the RPMs are far different, which makes a huge difference too! [/quote]
Nice to see forum members driving classic MB's. As for the shaking you might want to check your motor mounts. It's a common problem for all of these cars. When was the last time you adjusted the valves? Also, some injectors seem to work better than others especially when properly balanced. What ever you do please do not return you core Bosch injectors to the dealer. New bosch injectors are coming out of India. Keep your injectors and get better nozzles. You might already be a forum member at benzworld.com or peachparts.com but if your not you might want to join. I own a w116 300sd and a w108 280sel. I use Chevron Delo 15-40 and occasionally Shell Rotella 15-40 on my w116. Without oil analysis you really cannot say how long you should run the oil for so I would stick to the 3,000 mile interval. To say that one oil is better than the other is a hard thing to say without concrete evidence such as oil analysis ON YOUR CAR. Too many variables inside that engine to even conclude that just because your analysis shows great results that now such oil will react the same way in a different car or even the same model. Keep an eye on oil levels and give different oils a chance to see how they work with YOUR ENGINE. Some oils seem to work terribly inside my w116 and I get tired of adding quarts and quarts before changing the oil at around 3000 miles. Other oils APPEAR to work fine and adding oil between oil changes is not needed. Try oil analysis if you really want to know whats going on with your oil.....Your oil filter is also important. I use Baldwin, Napa Gold(wix) on my Chevy and Honda Civic and use Mann on both my Mercedes Benz....This is not a recommendation, these are the filters and oils that I use
Nice to see forum members driving classic MB's. As for the shaking you might want to check your motor mounts. It's a common problem for all of these cars. When was the last time you adjusted the valves? Also, some injectors seem to work better than others especially when properly balanced. What ever you do please do not return you core Bosch injectors to the dealer. New bosch injectors are coming out of India. Keep your injectors and get better nozzles. You might already be a forum member at benzworld.com or peachparts.com but if your not you might want to join. I own a w116 300sd and a w108 280sel. I use Chevron Delo 15-40 and occasionally Shell Rotella 15-40 on my w116. Without oil analysis you really cannot say how long you should run the oil for so I would stick to the 3,000 mile interval. To say that one oil is better than the other is a hard thing to say without concrete evidence such as oil analysis ON YOUR CAR. Too many variables inside that engine to even conclude that just because your analysis shows great results that now such oil will react the same way in a different car or even the same model. Keep an eye on oil levels and give different oils a chance to see how they work with YOUR ENGINE. Some oils seem to work terribly inside my w116 and I get tired of adding quarts and quarts before changing the oil at around 3000 miles. Other oils APPEAR to work fine and adding oil between oil changes is not needed. Try oil analysis if you really want to know whats going on with your oil.....Your oil filter is also important. I use Baldwin, Napa Gold(wix) on my Chevy and Honda Civic and use Mann on both my Mercedes Benz....This is not a recommendation, these are the filters and oils that I use
Here are some pictures of my Honda Civic 91. I'm the original owner and yes this is the original engine. Pictures also show my 1979 w116 300sd Benz (diesel) which is a true work horse.
http://share.shutterfly.com/share/receiv...7ea10c325bf4933
http://share.shutterfly.com/share/receiv...7ea10c325bf4933
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Originally Posted By: 83benz
I have four 1983 Mercedes Benz 240D's. I just got the 4th one last week and is the best addition by far with only 65,000 miles.
My question is if people here think that Mobil 1 TDT oil is the best oil to be using for these older diesels?
I have one that I bought 2 years ago with 185,000 miles on it that I switched from dino to M1-TDT and it started losing almost 1 quart/1,000 miles. I switched back to dino oil and the oil consumption dropped back to normal levels. Any ideas why synthetic would have been consumed at higher rates?
Any advice would be appreciated - I'm completely addicted to these cars and want them to last as long as possible.
Mobil TDT is a good oil, BUT if your old engine has layers of varnish helping to keep the seals from leaking then it might have dissolved some of the softer material and increased the leak rate. Synthetic oils don't damage oil seals but can change oil consumption in cases where conventional oils that lacked detergent have been in use. I changed from Mobil 10/40 to LM Synthoil High Tech 5/40 last year and even used an at idle only flush and my oil consumption for a 190K km 1.9TD is only 0.3 ltrs in 10K km.
I have four 1983 Mercedes Benz 240D's. I just got the 4th one last week and is the best addition by far with only 65,000 miles.
My question is if people here think that Mobil 1 TDT oil is the best oil to be using for these older diesels?
I have one that I bought 2 years ago with 185,000 miles on it that I switched from dino to M1-TDT and it started losing almost 1 quart/1,000 miles. I switched back to dino oil and the oil consumption dropped back to normal levels. Any ideas why synthetic would have been consumed at higher rates?
Any advice would be appreciated - I'm completely addicted to these cars and want them to last as long as possible.
Mobil TDT is a good oil, BUT if your old engine has layers of varnish helping to keep the seals from leaking then it might have dissolved some of the softer material and increased the leak rate. Synthetic oils don't damage oil seals but can change oil consumption in cases where conventional oils that lacked detergent have been in use. I changed from Mobil 10/40 to LM Synthoil High Tech 5/40 last year and even used an at idle only flush and my oil consumption for a 190K km 1.9TD is only 0.3 ltrs in 10K km.
Originally Posted By: JHZR2
All the w123s in mine and many others stables run great on 5w-40 and so Id run that over a 15wt.
Agreed! Don't use 15/40 in a diesel car unless you are in a very hot country or use some serious main block pre heater. 15/40 is only produced for 2 reasons, one it is cheap and two it is cheap.
Truck engines are different to diesel car engines and they were designed with 15/40 in mind, also many have a pre heat system and run for such long hours that cold start wear factors are only 10 not 50% of the total. Some good 15/40's do last longer than 5/40's, but very few owners are exploring the outer OCI limits, so that is a non factor.
If you get temps below minus 25C, then use an 0/40 as the cold start wear figures start to become more important, although if you have a classic car fit a big stick on oil sump pre heater or heat the garage before going cruising.
All the w123s in mine and many others stables run great on 5w-40 and so Id run that over a 15wt.
Agreed! Don't use 15/40 in a diesel car unless you are in a very hot country or use some serious main block pre heater. 15/40 is only produced for 2 reasons, one it is cheap and two it is cheap.
Truck engines are different to diesel car engines and they were designed with 15/40 in mind, also many have a pre heat system and run for such long hours that cold start wear factors are only 10 not 50% of the total. Some good 15/40's do last longer than 5/40's, but very few owners are exploring the outer OCI limits, so that is a non factor.
If you get temps below minus 25C, then use an 0/40 as the cold start wear figures start to become more important, although if you have a classic car fit a big stick on oil sump pre heater or heat the garage before going cruising.
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for those who like these cars and haven't seen this page.. http://www.mercedesmotoring.com
Originally Posted By: whizbyu
What kind of fuel economy can one expect from older MB TD's? Are there ways of tweaking the engines to squeeze more MPG's out of them?
The best MPG in the W123 chassis was the 240D with a manual. You could reasonably expect 28 in town, and 32-34 on the highway if you didn't beat on it...but you will find that if you beat on it, run it hard, you might get 0-60 in 20+ seconds...it was not a speedy car.
There is really no way to make any big improvement in economy. The engines were well-designed and well-built, they will run forever. The economy is in cost of ownership...not pure MPG...
What kind of fuel economy can one expect from older MB TD's? Are there ways of tweaking the engines to squeeze more MPG's out of them?
The best MPG in the W123 chassis was the 240D with a manual. You could reasonably expect 28 in town, and 32-34 on the highway if you didn't beat on it...but you will find that if you beat on it, run it hard, you might get 0-60 in 20+ seconds...it was not a speedy car.
There is really no way to make any big improvement in economy. The engines were well-designed and well-built, they will run forever. The economy is in cost of ownership...not pure MPG...
JHZR2
Staff member
Driving 55, my 240D with at has returned 35Mpg at best. Practically speaking, low 30s is doable highway. A 300d turbo is more like 28 but 30 if you're real careful. City of course will be lower.
Originally Posted By: JHZR2
I have a bunch of these and love w123 cars. Many have swapped their OM616/617 cars over to synthetics and love it. Besides easier starting, studies a while back indicated about 1/2 the rate of timing chain "stretch" (wear) when synthetics were utilized.
Many on their changeover to syn have seen consumption, though the rates often hve dropped unless there is a mechanical issue, by 20k miles or so.
If your engine is tight and sound, id definitely try to change over to TDT or T6. Both will perform well. Id personally use UOA to determine TBN loss and soot loading to identify an OCI.
Lots of these cars have gone well over 300k on 15w-40 and other oils, but I believe entirely that you cna do better with syn, and TDT is a great choice.
So less chain stretch based on using a different oil? Now that is interesting info.
Just a guess but maybe it's because a 5w-40 would be easier to pump,lubricating everything faster,which would mean the cam becomes less hard to turn,faster,which would stretch the timing chain less......
Just thinking out loud er,typing out loud er...you know what I mean.
I have a bunch of these and love w123 cars. Many have swapped their OM616/617 cars over to synthetics and love it. Besides easier starting, studies a while back indicated about 1/2 the rate of timing chain "stretch" (wear) when synthetics were utilized.
Many on their changeover to syn have seen consumption, though the rates often hve dropped unless there is a mechanical issue, by 20k miles or so.
If your engine is tight and sound, id definitely try to change over to TDT or T6. Both will perform well. Id personally use UOA to determine TBN loss and soot loading to identify an OCI.
Lots of these cars have gone well over 300k on 15w-40 and other oils, but I believe entirely that you cna do better with syn, and TDT is a great choice.
So less chain stretch based on using a different oil? Now that is interesting info.
Just a guess but maybe it's because a 5w-40 would be easier to pump,lubricating everything faster,which would mean the cam becomes less hard to turn,faster,which would stretch the timing chain less......
Just thinking out loud er,typing out loud er...you know what I mean.
Just thinking out loud again but would rotella t 10w-30 help this engine at all? May help fuel consumption and rotella is a known stout diesel oil.
Just a thought if it hasn't been suggested yet
Just a thought if it hasn't been suggested yet
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