WOW! Never heard of that oil sludge stuff before. V6 3.0 2002 ES300.... that's my car... I guess I should look into this. I change the oil myself and it's been perfectly fine, I've used everything from cheap dino to Rotella or Mobil 1 and anything in between. Typically we don't change the oil for 4-5k miles.
The oil is never sludgely or lumpy, just looks like used motor oil. We've got 100k miles on it. Maybe it's because we sometimes change it at 3-4k miles instead of the 5k posted in the service manual. I've never used the recommended oil though, it's a synthblend and I just do not like the concept of synth blends and feel like they could cause issues (sludge and oil seperation are my primary concerns).
Should I run some seafoam through on the next change and see if there's just sludge caked up there? Or peak in the valve cover when I do my timing belt?
makes me wonder if your periodic use of mobile 1 kept your motor clean. some of the members here like seafoam, so give it a try. and yes, do peak under the valve cover.
if you do find sludge, i've been told to run a good syn oil like amsoil or mobile 1for ONLY 1k miles before changing it again. this will clean up the motor, but the filter may reach capacity quickly. hence the short interval.
bowtieguy, congrats on the increase. Life is better when sprinkled with a lot of little victories.
I think the sludge thing is more a function of engine design rather than oil brand/type. BITOG discussions of sludge monster motors show that, regardless of oils/miles, some engines are just gonna sludge up while others don't.
Short, quick cleans with Seafoam have never done my engines any obvious harm, made the oil so dirty as to be pretty obvious it cleaned SOMETHING out, but did nothing to clean varnish off of non-primary wear surfaces. And I don't think a single short run of any synthetic oil would do much to clear a real sludge buildup or varnish. It certainly hasn't in any of my engines. Continued use may help, as would short changes. But for engines with obvious and copious amounts of sludge I would recommend Auto-RX (ARX).
Two of my vehicles (the V10 SuperDuty and the LS1 Camaro) got ARX to clean them out. Both showed dark brown varnish under the valve covers. The V10 threw oil around like crazy and after 2000 miles of ARX it was all shiny and new looking under the valve cover. After the same mileage in the LS1, which doesn't throw oil at all, there was no change.
Judging by the extremely positive cleaning action in the V10 I can say that ARX is some awesome stuff and cleans well when it touches something. I'm glad I didn't use it in the LS1 first or I wouldn't have thought it did squat.
Both had Seafoam treatments and did nothing for varnish.