Oil turning very dark real quick.

[krumpelsaurusrex]

So a few days ago I changed my oil. When I bought the truck the oil was very dirty, black to be exact. So I drained the oil and filled it with fresh oil. After checking the level it was a nice clean tan oil color. The truck sat for a few days and I checked the oil again today and it's already a dark gray color. I know that the old oil will still be in there without doing a complete flush (I don't want to do one). Should I just leave the oil like this for say a month or 1000 miles, the change it again, hoping it gets cleaner in time?

[DuckRyder]

Oil turning dark means it is doing its job (at least part of it) and the detergents are working. If the engine is sludged up you might consider using some gunk engine flush prior to the next change.

Changing it with the oill warm may help and also you could add a quart after draining and then drain the clean quart...

[mrsnicks]

Yeah, very possible the engine has been neglected and is very dirty with lots of deposits and sludge. I 2nd the recommendation that at the next oil change (whenever you want to do it 1k or 3k miles) that you add a quart of oil flush. You just put it in with your old oil, run it at idle in park for like 5 mins, and drain/change like normal.

Patrick

[NM5K]

I'd just change it out at the normal sked myself unless it's really looking bad.
Myself, I don't recommend engine flushes if the engine has the miles on it.
Good way to turn it into a smoker if it cleans "too well" and leaves excess
clearances. I'd just drive it and change the oil every 3000 or so. It will slowly
clean things up which is usually better than using a brute force method.
I've many a horror tale from the use of engine flushes in high mile engines.
Ditto for the power flushes many use on tranny's.

[krumpelsaurusrex]

Oil turning dark means it is doing its job (at least part of it) and the detergents are working.

That makes sense. I dodn't expect it to be as clean as it was when I put it in, and knew that it may take a few changes to look normal, but this dark this quick was a concern.

I'd just change it out at the normal sked myself unless it's really looking bad.
Myself, I don't recommend engine flushes if the engine has the miles on it.
Good way to turn it into a smoker if it cleans "too well" and leaves excess
clearances. I'd just drive it and change the oil every 3000 or so. It will slowly
clean things up which is usually better than using a brute force method.
I've many a horror tale from the use of engine flushes in high mile engines.
Ditto for the power flushes many use on tranny's.

Yeah, thats my problem. I don't have a reliable history on the truck or any work performed, so I just have to assume that nothing was done. Also unless it's well documented, there is really no way to know how many miles these things have on them. I have also seen engines become trash after flushes. My father was in the automotive repair industry until recently when he got real sick, and he would always tell me about the Bilstein flushes that they would sell. Most of the time it didn't cause any issues, but there were to many stories of the engine running worse after the flush then it did before the flush. Other stories of complete engine failure very soon after the flush. And I don't think it's the flush itself, but more so moving dirt and buildup to other areas that cause the engine to fail. I'll run it as is for a bit, knowing that the oil is fresh and change at 3 or 3000.

[garinger]

I agree with NO flush, just change every 3k or so and let the oil do it's job.

[sideoilerfe]

Change your oil and filter when it starts to get dirty. Do this a few times and you'll be fine. I NEVER let my oil get black. I bought a truck once and It had an engine that was really dirty and I changed the oil and before i started it i pulled the dipstick out and it was brown already. I drove it to work the next day and changed it when i got home. It was dirty again in about 4 days. I changed it again and it took 2 weeks before it was dirty again. I changed it again then and it's stayed clean ever since. Just keep changing the oil until it stops getting dirty prematurely.