It is normal. If you could actually get all of the oil out of the engine, cooler lines,etc, the oil would probably stay clear for about 500 miles. If the oil doesn't turn black right away, it probably is the WRONG type of oil.
when I first bought my truck, used, the first couple oil changes the oil would stay clear for many many miles. happed for say..the first 3 changes, each change was done on a monthly basis due to sitting but still had miles on. then all of a sudden it went away. never been like that since. now first crank with fresh oil turns it black.
The additives in the oil break down the carbon particles so your filter doesnt plug up with soot. On every engine I had it would get black after 2 hours or usually less then that and would be brown after the first start up. Even my 3.5 hp lawn mowers are like that. In my jimmy with a 4.3 liter I put amsoil full synthetic in it. Ever since I did this the oil is a little brown after 200 miles. With regular oil it would be black by now. I dont know why it is but I was always told black oil is good because it is cleaning so I gont know if I like what Im seeing with this amsoil.
So do you see any advantage to running Amsoil? run cooler? better fuel milage?
I watched as a guy changed oil & filter 5 times and still had black oil. I think he sold his truck. The mechanic just smiled, the service mgr. just let the old guy spend his retirement money. I got the impression this was the guys first diesel, he complained that it was slow and noisy, Dodge Ram with a gooseneck camper.
I thought it would start up easier in the winter, it did just a little but barely noticable. As for better gas milage, maybe but its got around 180,000 miles and needs a tune up. If its really is 82% more friction resistant then conventional motor oil then I would say its worth having. A oilchange every 7500 miles is recomended. A freind works a a quick lube and says people come in with mobile 1 synthetic after 15,000 miles for the oil change, thats what is recomended, and they said it was almost like tar. I also thought my oil pressure would stay the same hot or cold but it didnt.
The only good reason to use synthetic in a 6.2 is for cold starting ability in the winter, rotella 5w40 is a good buy at walmart. As for extended drain intervals on a 6.2, don't do it or you will suffer premature engine failure!
If it gets better gas milage and has the wear resistance then I say use it. I like amsoil but would stay away from mobile one, they say only change it every 15,000 miles, I dont like that. Amsoil isnt much more then good engine oil and you change it every 7500 miles and a filter every 3000. Since I just started using it in january I havent found anything bad about using it yet.
Premature engine failure? If you change the filter often I wouldnt think it would be a problem, if your one of those morons with mobile one that change the filter and oil every 15,000 miles then Id be surprised if you make another 15000.
Premature engine failure is from the carbon that gets suspended in the oil. Very few 6.2/6.5 engines can tolerate more that 5,000 miles between oil changes do to the amount of carbon that builds up in the oil. Carbon acts as a cutting agent and when levels get too high, internal parts start suffering premature wear.
When amsoil first came out in the late 70's, I was one of the first to try it. It was said that oil changes could be stretched to 25,000 miles. I ran it 10,000 miles on a fairly new 350 and after 10,000 miles, the engine was running 25 degrees hotter than normal. A switch back to valvoline restored engine temps to normal. So much for less friction! If running synthetic for lubrication benefits, don't run extended drain intervals. Drain intervals vary with different types of diesels also. I just changed the oil in my 01 duramax at 7700 miles and it was still semi transparent.
Synthetic oils are not good for older engines, unless synthetics are used in the vehicle from new or fairly near new they acually create more problems than they fix. The reason for this is the fact that a synthetic oil any kind, tranny, motor, gear, all act like engine cleaner or almost a degreaser. To help understand this let me explain. Molecules of synthetics are uniform, meaning every molecule is exactly the same every time, with nothing extra. Regular oil has molecules with different shapes and sizes and extra stuff mixed in that just cant be refined out. A car that runs syn all its life sees no changes that are unordinary, even if it is switched to regular when it gets older cuz who wants to spend more on oil than the car is worth. On the other hand an engine run on regular oil its whole life that gets switched to full synthetic will have issues. Nothing terrible mind you, but you will experience more oil leaks and sometimes worse performance. The reason is that syn acts like a cleaner removing the extra things that reg oil has in it and synthetics can find and pour through holes that regular oils can plug. Thats gasket holes and any other place that the tiniest debris can plug. Its almost as if synthetics have a lower viscosity when is comes to oil pressure whether it be in your engine or transmission. It is just not recomended to switch from regular oil to synthetics. Unless you are changing ALL your gaskets and eventually the oil/fluid pumps. Hope this explains it well. I truely believe in frequent oil changes. Oil is cheap insurance especially for an engine that runs in it, and on it.
well, I wish I would have read this before. I already changed it to synthetic 10-30. Well, I am keeping it in there till the next oil change b/c it was expensive. I will use rotila or whatever its called next.
WOW you guys really slammed the sythetic oil. I went from regular oil to amsoil but I am on my first change so maybe Ill go back to the regular. I have no trouble yet but its also only been 2 months, well almost 3.
As for the carbon in the oil, if you change the filter often it should filter it out of the oil so the carbon isnt a problem. Also when I went through the quaker state lubracation education program they said that the aditives break the carbon particles up small enough so they dont cause any damage. If you have to much carbon from not changing the filter then it will just make the oil thick and nasty and then could cause damage.
my 6.5 takes 7.5 quarts and I use 1 gallon of 5w-40 Syn Rotella and 3.5 quarts of 15w-40 Rotella, keep the last half quart for top off, I drip 1 quart every 3000 miles.
Anyway, As an attempt to 'flush' some old oil out of the engine, when I get home in a week and a half, I'm gonna change the oil, drive about 100 miles and change it again, maybe repeat. Figure it cant hurt to get a better percentage of fresh stuff in there...
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