So I run the Auto RX thru my Bronco 5.0 that has 125,000 miles on the clock. It has had the oil changed every 3500 miles like clockwork. I usually use an HDEO like Rotella or Mystik in 15w-40. I run the Auto RX for 2500 miles using Havoline 5w-30 for the cleaning phase. The oil was nasty to say the least and even smelled bad when it came out. I run the same oil in the rinse phase expecting to see it turn nasty as well and it is just as clean today at 2000 miles as when I put it in. I even polished the dipstick to a chrome like finish so you can see the oil on the thing- its almost clear. Did something go wrong or were my expectations of something nasty during the rinse cycle a little off base? I always allow the oil to drain for several hours to get all of it out.
FWIW, the engine was developing a minor rear seal leak. It no longer leaks and the cost of the Auto RX is rather small as compared to new seals.
I think you'll find that when you drain that rinse oil out it will be black, some of it may even be sludgy. Too much emphasis I believe is placed on what it looks like on the dipstick.
Trapper, This may just be a very good success story, it cleaned faster in your Bronco than usual perhaps. Question, was you oil dirtier than usual after your Autorx cleaning the first time, or was your oil always nasty after a change?
You have a highly efficient big V8 as far as oil FLOW goes, so sludge is less of an issue than say a 4 banger. It's possible you got the cooties out of the car in the first phase meaning you just didn't have that much sludge to worry about. If you really want to know pull valve covers and looky look. Bronco's are not known for sludge problems at all.
In many cases the crud drains out from the cleaning phase oil dump. I have seen it myself in a 4.3 liter GM. For whatever reason others see more during the rinse phase. If I were you, I'd be happy about what you drained out after the cleaning phase.
Shelby, the oil almost always came out a golden brown color, never black, when changed. The old girl has never used any oil between changes either and the leak was minor as in leaving just a few drops of oil on the drive between changes. I'm not complaining. I used the Auto Rx for hopefully stopping a minor oil leak. Anything else was really icing on the cake. The leak has not returned but I'm not thru the rinse phase just yet. The oil is still fairly clear on the "chrome" stick with just a slight hint of golden brown. I'm about 500 miles from a change so my expectations are that it won't get much darker. I'm pleased with my investment. Now if I could only find someone that could do a fabulous paint job.........