Ok so I came across some pics of a 60k BMW engine with the valve cover removed. Look at all the sludge. This is why all you need to change your oil every 5-7k miles. Just for comparison the bottom shows a pic of one of my BMW customer's engine, that has 160k on it and oil been changed every 5k, may I also note he hasn't had any engine problems, coincidence I think not. This looks new, even with 160k.
What's the story on the gunked up engine? That isn't from synthetics every 15k.... There's got to be more to the story... Matt
Gosh this is getting all over the internet now. Wish I posted in the original thread over on bimmerforums for posterity! It's actually funny - people from all over are joining just to post in the thread.
On the sewing site there is talk of using a product called Seafoam introduced through the PVC. Intent is to clean out allot of this sludge. I do the 5K oil changes but was curious of anyone else adding the Seafoam in addition
This is a similar thread on this site: http://www.motoringalliance.com/forums/cooper-clubman-engine-drivetrain/2002-how-seafoam-treatment-r55-r56.html
For most cars... running new synthetic oils, sludge isn't a problem (Toyota had an issue around 2000 though where sludge in too small oil galleries resulted in some engine fialures) so 20k+ service intervals aren't as bad as they would have been with leaded gas, dino oil and the like for cars of the 60s or so. You still have to top up the oil more often though. Personally, I've never used the Sea Foam in the crank case. While I'm sure it's not bad, it will thin the oil a lot when it's in there (they say don't drive hard). It just rubs me the wrong way. Matt
I'd estimate about $400 if they'd had the dealer do the services, the first 36,000 miles are free (10K and 25K mile changes) and the next two changes (40K and 55K miles) would've been about $200 each I guess.
I admire you guys for thinking proactive about seafoaming the engine and using other treatments. But take a good look at the pic I posted of the 160k engine, it never had any seafoam or other engine treatments done. Just 5k oil changes. Basicly making the point that just more maint will take care of the engine, rather than rolling the dice on snake oils, Now I say that lightly but all these treatment products make a bunch of claims that we all know they arn't all true. Dr O, sorry but I disagree about synthetic oils not sludging. I can't tell you how many 60k+ mile BMW's that I have had the valve cover off or been in the engine and found alot of sludge. So synthetics do sludge, I garuantee it. Obviously the sludging is more so contributed by the long oil change intervals. But Dr O is right that Synthetics are designed and have better additives to prevent sludging over standard oils. But heck Man designed them to be better, and they are.
I think we basically agree... basically good maintenance will deal with the problem. 60k without changing the oil will just build up lots of crap, no matter the lubricant! Matt
Regarding Seafoam etc.... I'm with Way and the Doc regarding the crankcase - regular oil changes with the right oil are all you need there... but I think most of the benefit to cleaners are for the injectors, intake tract, and head. But top quality fuel additives (e.g. Techron, Shell V-Power) and water/meth injection will do the same thing for you... I run good gas, occasional gas additive and water meth - but bought a can of Seafoam and will run it through the fuel and intake because, at 60K, I figure it can't hurt...
Color of oil on dipstick Is the darkened color of the oil on the dipstick a good indication that it is time to change the oil? I've noted that the color of the oil on the dipstick becomes noticeably darker at around 3-5K miles of use, which is about the time I change the oil anyway.
Well..... non-dark oil is certainly "fresher" than dark oil... but just because it's dark doesn't mean it needs to be changed. Only oil analysis can REALLY tell you what the right mileage intervals are on a specific car with specific driving habits and other factors. In industrial environments, they often do oil analysis on individual pieces of equipment to determine the optimal maintenance schedule for each piece - two pieces of "identical" equipment sitting side by side running the same workloads may have different maintenance requirements - just due to differences in manufacturing tolerances, etc. (e.g. how tight do your rings fit?)
I was seriously thinking of seafoaming my engine recently but when I went to change the plugs I realized that they were about as good an indication of the cleanliness of the inside of my combustion chamber as anything and they looked really good. These particular plugs were about two years old and have over 30K miles on them so they weren't fresh but I've taken worse plugs out of cars with only 20K miles. The only real additive I've ever run was a bottle of Redline injector cleaner/fuel additive a year and a half ago. I do my oil changes at 7500 miles and the oil is darkened (and no longer purple) but still translucent, I've never done an oil analysis but if I were to go by the OBC my oil changes would be closer to 20K miles apart so I take that to mean I use my car somewhat gently.