For engine oil, or tranny fluid, or antifreeze, or brake fluid or any other fluid. At what level do all you use and is the reasoning why?


I always try to be about at the 1/4 to 1/2 mark above minimum.

 

I shoot for the full mark or a little bit below it. That way if you're burning any oil (or loosing fluid) its easy to remember what the level was originally. The only thing I don't keep at the min level on my truck is the coolant. For some reason it always goes back to the same spot half an inch below the min mark. Its not just on my psd either....

 

I always go all the way, has worked for me for many years.

 

All the way full, but measured when everything is at operating temp.

 

Ditto for me.

 

I normally try to hit a full mark as close as I can. However, you've got a 6.0 PSD, so there are a couple of oddities. On your coolant degas bottle, the molded in C and H marks are too high. Ford had a TSB specifying that the Cold mark should become the new high mark. Many trucks have a decal stuck on to tell you this, but most don't. So when your truck is fully warmed up after a good drive, your coolant level should be on the COLD mark. Obviously it will be below that when cold.

For oil on the PSD, they have a crappy dipstick and it is very difficult to read. I have found that the only way to get an accurate read is when the truck is cold and has been sitting overnight. Then just pull the stick and read it. I also shoot for the halfway mark on my PSD oil. This is partly due to the difficulty in reading it, and I want to be extra sure that it is not overfilled. It is also partly due to a condition where the engine will "create" oil, actually from fuel leaking into the oil. If that should ever happen, I want to be able to easily see that my level is increasing. Between full and low on the dipstick is 2 quarts on that engine, and it holds 15 quarts, so my leaving it 1 quart low in the middle of the dipstick does no harm. Saves me a quart at every change as well.

For the Torqshift, I shoot for full on the stick, but take extra care to not overfill. It is bad for most trannys to overfill, and especially on the 5R110. It may well blow it out if you do.

Those are the only critical items.

 

+1 on Bill's comments, I do the same.