Looking at 6.0 - tan sludge?

[Korx]

Hey guys, I have been browsing this forum for a while now while in search of a new truck. And I would first like to say thanks for all the tips and pointers I got when looking through threads.

Now I think I found a truck that I may be interested in, its a 2004 f250 ecsb with 149k on the clock. I went to look at the truck and I did not spot any leaks on the underbody or the ground. It looked like there was a little oil residue from a while ago on the intercooler boot but other than that it looked good.
Now to my question, I stuck my finger into the degas bottle and pulled it out and the coolant appeared to be gold. I stuck my finger in again until it hit bottom and I pulled it out and it had some tan looking sludge on it. That is the only thing I am worried about does anyone have any clues or ideas on that sludge?
There is also a fifth wheel hitch in the bed and it sounds like the PO used it to tow horses on his farm. I read somewhere these trucks like to be worked so is that a good thing?
I did read all the threads about what to look at when buying a 6.0 but I got several different responses about the sludge.

Any tips or advice would be appreciated, thanks guys.

[jimmyv13]

This is a pretty good read:

Things to consider about owning a 6.0L

[Korx]

I have read that a few times. I am assuming its a plugged up oil cooler? Does that sound correct?

[cartmanea]

Tan sludge could be silicates that have come out of the coolant, especially if it's never been changed since the factory. Could also be the think milk-shake sludge you get when oil gets in the coolant, which could indicate an oil cooler with a small leak.

[2006PSDSD]

The oil sludge should float though. Probably the silicates from the coolant. As him for proof of the last time the coolant was flushed or replaced. If he's never done it, knock a grand off the price because that oil cooler is not long for this world

[2006PSDSD]

Oh yeah

[jimmyv13]

If you're serious about purchasing a used 6.0L, you may want to invest in a scangaugeII. It will give you a pretty good idea of what condition the engine and it's components are in before you buy. You really want to see what the difference in temperatures are between the coolant and oil. The closer you get to a 15 degree separation between the two, the more plugged the oil cooler is.

[Korx]

The guy hasn't owned it long, maybe a month or two. Before then it was owned by one owner who traded it in, so no records. Is there anyway to tell the difference between silicates and oil? I don't have anywhere where I can readily get a scangauge or an edge insight.

[Hoder]

Originally Posted by Korx

The guy hasn't owned it long, maybe a month or two. Before then it was owned by one owner who traded it in, so no records. Is there anyway to tell the difference between silicates and oil? I don't have anywhere where I can readily get a scangauge or an edge insight.

I would consider it a red flag that someone is trying to sell a vehicle they purchased a month or two ago... What changed his mind?

[Brieldo]

Originally Posted by Korx

The guy hasn't owned it long, maybe a month or two. Before then it was owned by one owner who traded it in, so no records. Is there anyway to tell the difference between silicates and oil? I don't have anywhere where I can readily get a scangauge or an edge insight.

A. See if you can get a dealer to give you an OASIS report on the truck.
B. There are tests for coolant that will tell you what's in the coolant be it hydrocarbon-based or something else.