Changed my oil, now it's black as pavement-why????

[fattypackard]

thanks for the info!

 

[JoshRountree]

so this thread has heightened my curiosity...i have a 98 XJ w/ 146K....runs fine, no leaks no burning oils or anything...but would it be a good idea for me to start using 15/40 diesel oil ?
what exactly are the pluses and minuses?

sorry about the hijack.

More info than you could ever want about oil in an XJ.