I'm just getting around to changing oil and filter in my 85 6.9 that I bought. Question is, how much oil does it take with an oil and filter change? Also what weight of oil is suggested?

 

Oil capacity is 10 Qts. with stock filter. I use 15w40 fpr weight.

 

15w40 or sae 30
oil level is checked with the engine hot
oil level rises as oil is heated and expands

 

10 quarts stock, 11 quarts if you use a PSD oil filter. I would actually recommend that you install the PSD filter, as it both is larger and filters better.

 

CD or CE is the minimum API spec as well.

 

i used the PSD filter once i liked it till i changed the oil next time. it was just long enough that it had to be tilted to get it off and out. so after that nice day of oil running down my armpit i figured iy wasn't worth it for me

 

If you look at the angle the filter header sets at, it don't make any difference if you use a long or short filter.
They both will be tilted just enough that oil will run over the side when you remove it.

The only way around that is drive a center punch in the bottom of the filter and let it drain before you remove the filter.

 

Try changing one on an intercooled first-gen. Dodge-Cummins.
You CAN'T get it out with out turning it 90* and spilling it all over your front diff.