Just got done doing some upgrades to the dak... iinstalled a K&N kit, autolite 3923's & wrapped the fuel rails. Found more sludge at the oil fill tube so the motor flush must be doing its job (MMO is what I used, 1 quart).

1st impression of the updated setup... Nice! breaths much better in the upper rpms now. truck sounds awesome (flowmaster exhaust) and scoots pretty good now as well. I doubt there will be any change in the mpg as the lower rpm power feels the same. time will tell...

 

i think the sludge in the oil filler tube is something that happens in colder temps because the filler tube is plastic or whatever and heats up differently then the block or whatever not sure on the exact reasoning but its a fairly common problem that i've read about on other forums so i dont even worry about it anymore if you find a way to reduce it though that would be awesome.

 

yea actually now that u mention this i remember reading a topic about this and it being normal on these trucks.

 

Normal or not, there has to be a way to prevent the buildup. One thing I noticed was that when I put in the Mobil 1 15w-50 (my 1st choice), the motor seemed to rev the same. after about 400~500 miles on the oil, it definately has a greater load on it. this is telling me that the sludge is getting cleaned up and is now probably flowing into the filter. The 1st time I cleaned it up out of the filler tube, I left the oil in there and ran another 500 miles w/o any more buildup (was keeping an eye on it)... since the swap, more gunk started flowing. I was pretty close to changing it today but decided that with only 400 miles on it and it being mobil 1, I should leave it for at least 1k. when I do swap it I'll go with a cheeper oil that I can flush sooner. I'm thinking I'll flush with dino oil 2~3 times or until I no longer see the sludge buildup. I'll keep you guys posted.

I've read that some owners with the same 4x4 QC 4.7 config were getting 20~22 mpg on the hiway... that would be hella nice since I run 170 miles/day to work& back. (mainly driving the ram since it has a 600 mile range)