In the stable, we currently have 2 Mitsubishis:
1) 1997 Montero Sport, 3.0l V6, 101k miles. Wife's car, daily driver, sees about 50 miles per day of to and from work, most of it being 50-55mph. It's only when she goes through town that she has to drop to 25 mph.
2) 1987 Montero, 2.6l I4, 143k miles. My rig, only driven occasionally (roughly 8k per year) mixed driving, roughly 1/3 of that on rough logging and gravel roads.
We live in Western Oregon, so winter temps are rarely below freezing and summer temps are only occasionally above 95. We are both easy drivers; we avoid hard stops and starts, etc. Neither rig does much stop-and-go in traffic, and because of where we live there is no such thing as a "short trip" - any drive we make is a minimum of 20 miles, usually more like 50-60.
Both vehicles are in very good repair (I maintain them scrupulously), no known issues.
The owner's manuals are vague on viscosity recommendations. Based on what the local Mitsubishi dealer told me, plus the lookups I've done on the oil maker's sites, I've been using 10w30 in both vehicles. I usually use Havoline (Dad was a Texaco station owner - old habits die hard!), but occasionally Castrol GTX. Filters are Purolator Pure 1 or NAPA Gold (mostly the former.) I change the oil every 3k miles.
My main question: have I chosen the correct viscosity oil? Given the mileage (particularly on the 1987), should I be using a 10w-40? I think I'm comfortable with the 10w cold rating given our mild winter climate; it's the hot rating I'm more concerned with.
1) 1997 Montero Sport, 3.0l V6, 101k miles. Wife's car, daily driver, sees about 50 miles per day of to and from work, most of it being 50-55mph. It's only when she goes through town that she has to drop to 25 mph.
2) 1987 Montero, 2.6l I4, 143k miles. My rig, only driven occasionally (roughly 8k per year) mixed driving, roughly 1/3 of that on rough logging and gravel roads.
We live in Western Oregon, so winter temps are rarely below freezing and summer temps are only occasionally above 95. We are both easy drivers; we avoid hard stops and starts, etc. Neither rig does much stop-and-go in traffic, and because of where we live there is no such thing as a "short trip" - any drive we make is a minimum of 20 miles, usually more like 50-60.
Both vehicles are in very good repair (I maintain them scrupulously), no known issues.
The owner's manuals are vague on viscosity recommendations. Based on what the local Mitsubishi dealer told me, plus the lookups I've done on the oil maker's sites, I've been using 10w30 in both vehicles. I usually use Havoline (Dad was a Texaco station owner - old habits die hard!), but occasionally Castrol GTX. Filters are Purolator Pure 1 or NAPA Gold (mostly the former.) I change the oil every 3k miles.
My main question: have I chosen the correct viscosity oil? Given the mileage (particularly on the 1987), should I be using a 10w-40? I think I'm comfortable with the 10w cold rating given our mild winter climate; it's the hot rating I'm more concerned with.
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