A friend of mine has a Subaru WRX that burns a lot of oil. She took it to the dealer complaining, and they said it was "normal" for that motor to burn 1 qt per 1000 miles <img src="/forums/images/graemlins/zombie.gif" alt="" />. I couldn't believe she was telling the truth until I looked it up, and sure enough there are hundreds of posts from around the globe on people with the same problem, and subaru giving the same response. So by Subaru standards, your motor is better then brand new! <img src="/forums/images/graemlins/ignore.gif" alt="" /> As for change intervals, I've often felt every 3k miles for changes was too much. Most people don't drive their vehicles under "severe" conditions all the time and tend to follow the "normal" driving intervals which are typically 6k-7.5k mile intervals. Popular Mechanics did a year long study on change intervals with conventional and synthetics following "severe" and "normal" intervals (3k and 6k on conv, and I think 5k and 10k on synth). At the start, they rebuilt all motors and measured everything, then at the end tore the motors down and measured for wear. There was little wear difference between all of the motors, so little that they determined it didn't matter what oil you used. Of course this was quite a few years ago, and they didn't include a fuel consumption factor in (which I think the synthetics would have shown a slight improvement in over conventional oil), and since all motors were freshly rebuilt, didn't factor in the extra "dirt" that a worn motor can create in the oil. If you're a casual off roader, I'd say change the oil after the off-road trip and use the longer "normal" interval between off-road trips.

It's better for the environment to have less oil to dispose of and the cost savings for little extra benefit will add up over the years.

The 87 FSM has normal usage changes at 7.5k miles for oil and every 15k miles for the filter and severe is 3k for oil and every 6k for the filter.

just my 2 cents <img src="/forums/images/graemlins/cheers.gif" alt="" />