I have read about the condensation problem some here are having. All of a sudden, my 04 screw started having the same white junk under the oil cap. The question is whats causing the condensation problem in the first place. A clue is, my wife got my truck fully detailed for Christmas since I havent had any time to do so. The detailer said he cleaned the tail pipe out which was an added chrome piece. I also have a single flowmaster exhaust. Upon taking off from the detail shop I noticed a rattlin noise coming from the exhaust system. Usually it is loudest when I'm taking off from a start. Sounds like its coming from the flowmaster. Another clue, my gas mileage has gone from 22 mpg to 18mpg on the Hwy (no kidding, 355 rear end). Does anyone here know if the water the guy sprayed into the tail pipe possible messed up the flowmaster and now is causing the condensation problem and loss of gas mileage (engine not breathing properly). All this happened at the same time when I got the truck cleaned. Does it sound like I need a new muffler? The truck has 106K on the OD and runs like a top, with new plugs and about everything else due at 100K for maint. Thanks for the help.

 

the condensation under the 710 cap is most likely nothing to worry about. sometimes moisture can get in during oil changes or the cap doesn't seal completely. keep an eye on coolant levels and make sure it doesn't drop or start turning dark.

check your heat shields on the exhaust. they can sometimes get loose and when the exhaust vibrates it hits them.

do your scheduled maintenance and see what happens with the gas mileage.

 

More than likely normal condensation from short trips, cold weather. Take it out on the highway for 10-15 miles then check it again. That will usually will cook it off until the next short trip.

 

A bad PCV valve will also prevent the condensation from going away and you will get the foamy 710 cap.

 

One of the baffling plates in the muffler might have broken apart from the muffler walls.

 

Yep.

Your RattleMaster needs to be replaced. Hopefully with a real muffler this time, that wasn't designed by a couple yokels scratching diagrams in the dirt with sticks beside their still while waiting for more moonshine to cook

If yer detailer caused this (unlikely), then consider it fortuitous.


What FartMaster engineers do in their spare time:

 

 

I've got the same problem. Are you saying I need to upgrade my oil cap to a 710 cap? Never thought of changing the pcv.

 

Thanks for all the replies. I thought about the PCV valve but didnt know if it even had one. I looked around and didnt see it. Maybe its hid under all that other stuff. I used to be able to change PCV's once upon a time. Maybe this is also the answer to my lack of MPG's.