The nice thing about diesel oil is that it is highly detergent and will flush your engine as you drive without clogging anything by breaking a huge chunk of sludge loose.
And because it is cheap if you have a sludge problem you can afford to go with really short oil changes to get the best "flush" possible.
Be aware that you can expect increased oil consumption until your engine seals get soaked with the new oil.
Do not be alarmed, it will stop after a oil change or two.

 

The last five oil changes or so have been synthetic oil. Recently I had my Discovery serviced for a leaky t-body gasket and the shop told me to use conventional oil. Thoughts on this since I've been religious about synthetic oil. I know that it's an older design and require detergents.

Thoughts?

 

Use whatever makes you feel good. Shops worry about synthetics because switching to syn can cause extra consumption and leaking for a few oil changes and that can cause them headaches with customers. Also some people just have weird ideas about oil. What synthetic oil will give you is better cold flow performance and will handle high temps better. Today's convention oils are better than ever though and the line between syn and conventional is going to get fuzzy with GM's new dexos oil standard and the new SN oils that must meet it.

 

At the beginning of this thread the wix 51515 filter is mentioned, but the wix website filter lookup recommends the 51068 for the DII (both engines). Any reason to use the 51515 vs. the recommended 51068?

Thanks

 

the 51515 is the longer version. I like that there is more filter media and it adds more to the overall volume of oil. Both are pretty minimal "pluses" so use whichever filter you feel comfortable with.

 

Thanks for the response, minimal pluses are still pluses, I will go with the 51515.

 

You can also use a Mobil 1 301 oil filter, it is also a longer version of the standard size and sometimes easier to find than the Wix.

 

or the napa gold 1515 version made by wix or purolator pure 1 PL30001 or K&N 3001

 

Where can you buy this oil by the quart at a good price? I stopped by Auto Zone and they sold it by the gallon. Tomorrow I'll stop by Walmart or a Shell station. Auto Zone did not have any of the larger filters mentioned.

Thanks!

 

For the Rotella go to Wal-Mart or Tractor Supply Company, you will need to buy 2 gals of it, but thats ok because you will have extra for adding if needed and for the next oil change.
At Wal-Mart its $18 per gal for the 5w-40 TSC $20, if you buy just a quart it will be around $6, so just buy a second gal.
As for the oil filter, if you want a Wix or Purolator you will need to go to NAPA or Advance Auto.
I recommend and use NAPA (Wix) or Purolator, if you keep your eyes open NAPA often has a buy one get one free sale on filters.