Hey, I noticed when I looked into my oil fill, I could see some buldup of sludge and what not.Even though I wasn't near my oil change milage, I decided to change it anyways. I use Mobil 1 full syn.and K&Noil filter. Well,while I was at the store picking up some things for the car, I noticed a bottle of Marval Mystery Oil. So Ibought itwith the rest of the things. Right before I changed the oil I poured the Mystery Oil in and ran the car for about 15 Min at differant rpms. High for a few, then idle and everything in between After I let it cool for a few, I took the plug out of the pan and couldn't believe what was comming out. It was thick and very nasty!! When It stopped flowing, I poured a bottle of regular oil to finnish flushing the engine, and changed the filter. After putting it back together, I looked into the oil fill again, and now it's clean and shinny like it should be! I took a long road trip up north and my gas milage has even gone up, now I get more then 30 MPG on the freeway! I think I'm going to do this everytime I change my oil.

I didn't see any problem doing this and it seems to have helped my car out a bit, I know a littlebit of the Mystery Oil stayed in the car, but I don't see that being a problem.So give your thoughts and feed back to wether it was a good idea or not. Maybe this will help clear up sludge problems some people are having.

 

Sounds like someone before you got cheap and used dino oil more than once. If you use the recommended oils you wont have to do this again. Plus if you switch to the larger a4/passat filter you can hold more oil and help to lower the chance of sludge build up further. But im glad you back in the fuel milage as you should.

 

i've heard its okay every now and then. not so sure i'd make a habbit out of it. seemed to work though, thats good!

 

The main thing is to change you oil frequently, every3K-5K; the "official" 10K interval is absurd. Also the stock filter is plenty big for 4.8 quarts; the frequency of changes is everything.

 

More oil means lower oil temps and reduces the possibility of sludge. That is the point of adding a bigger filter.

Also i have seen plenty of oil anaylis to feel more thancomfortable to change my oil in the 7-8k mile range. Syn oil does not break down like dino oil and can take the temps much better than it also. If you use the the approved oils you will be more than ok to take it beyond 7k miles.