Mobil 1 High Mileage 5w30 is now SN rated, so I'm now 2800 miles into it and it appears to have reduced consumption by 30-40%. So far, so good! I'll probably run 10w30 M1 HM this summer.

 

The 3.8 was originally designed to run 10w30 oil so its no surprise to me that some burn oil.
At 266,000kkm mine burns about 1/2qrt in 10,000klm a little less with Amsoil 5w40 European blend.

 

Viper TB is what I'm rockin. TB spacer does nothing. I also have no hard data except for my own experience driving. A lot less lag when you step on it.

 

Threw a Cyl 6 miss fire on the 2012 JKUR with 48000 miles. No other indications of problems but still had a code (will have to find out what code) and now I worry.....

 

You have the 3.6 mate

 

207000 miles on my 2008 JKU, running 3 inch lift and 35 inch tires....other than a K&N air filter have done nothing to the motor. I have taken it everywhere from the NJ Pine Barrens to Logandale and other than being ridiculous about maintenance and fluid changes no issues...the exhaust manifold has been replaced twice, and all the catalytic converters have been replaced.

 

2007 JK Sahara, stock drivetrain & suspension, 68,XXX miles.

Started missing and blowing white smoke/vapor REALLY BAD last week so I put it in the shop of a mechanic I know and trust. Head gasket blowing coolant into #2 cylinder!

I'm pretty pissed that a component that should last essentially forever would fail on a vehicle that has had one owner and excellent preventive maintenance! This engine has NEVER been hot, out of coolant, etc. In fact, I have installed an auxiliary fan in front of the tranny cooler (both installed by me) that I often run during hot weather as it improves performance of the A/C.

My mechanic says that head gaskets are really common replacement items nowadays. I'm old enough to remember head gaskets that lasted for decades. What the heck happened?

 

You're not driving it enough 152k on the clock of my 2010 and it does what it's supposed to do.

 

I have 175,000, no head gasket problems. Have had any other work done to it like the intake manifold gasket replaced?

 

Yeah, I replaced the leaking intake manifold gaskets myself a few months ago. All for nought as both heads were pulled last week