TJ2
TJ Expert
Rooscooter, not everyone has that luck like yours. You may have just jinxed it
Could be.... I use 10W30 and haven't heard any difference.... but then again I put in a really good stereo and speakers....Rooscooter, not everyone has that luck like yours. You may have just jinxed it
I agree. I don’t think synthetic would make an engine leak, but my Jeep has 88k on the clock. And apparently the seals were hard enough from earlier use that they seeped quite easily.Using synthetic oil won't cause your engine to "develop" leaks, but if your engine was seeping oil from hardened old seals before, it can cause more oil to get by the seal.
Synthetic oil has better cold flow properties and withstands heat better, but for most of us just using a cheap oil and changing it often due to the dusty/dirty off road environments our Jeeps see is the most cost effective option. I've actually run used oil analysis on my previous 4.0 Jeeps (not this one yet) and plain 'ole Pennzoil conventional 10w30 seemed to show the best wear numbers. With the 4.0L it doesn't really care what is in it, just change it regularly and keep it full. A high mileage oil like Valvoline MaxLife 10w30 contains seal conditioners that can actually slow down small leaks (like a seep) but won't fix bad leaks like a rear main seal or valve cover gasket that is significantly leaking.
Severe duty is considered any condition where the vehicle is used for towing, mountain/hilly areas and high traffic areas where the vehicle is sitting in stop/go traffic or idling for extended period or traveling at higher rates of speed.
Being a GM technician, I can tell you draining the oil out of a 4k mile vs 7500 mile engine is a difference of night and day.
I can also tell you that the engines that see a more frequent service interval are the ones that last longer.
Most of the engines I tear down for internal problems are due to extended service intervals.
So to me changing the oil every 3-4k miles is not a waste of time, it's preventative maintainence that will extend the life of your vehicle.
GM vehicles have a oil life monitor system and yes you could get 7500-10000 miles before the oil life hits 0%, but we still recommend every 5k when using GM Dexos synthetic oil.
I've used the same and have had nothing but good results from this same oil. No lifter noise/tick or anything. The major leak i recently had, I thought was a rear main seal but it ended up being the oil pan itself.Interesting..... I've used the Pennzoil Platinum Synthetic high milage formula for a couple changes now and haven't noticed any lifter noise. I'll have to pay closer attention maybe....
My RMS was not leaking.Using synthetic oil won't cause your engine to "develop" leaks, but if your engine was seeping oil from hardened old seals before, it can cause more oil to get by the seal.