mjmcg
Junior Member
Howdy. Curiosity item.
2011 1500 5.7/5 spd.
When on the highway @ 60mph on cruise, flat terrain the engine settles in at 1,700rpm.
If I bump the cruise up 3 times to 63mph the rpms will rise to a 1,900 spike then drop to 1,500rpm where it will stay for the remainder of my trip.
Now here's where my curiosity kicks in as I'm not a stranger to auto trans or converters. I'm not a know-nothing novice, but I'm not familiar with this particular behavior.
Sometimes if I achieve 60mph and set my cruise on a slight downhill grade it'll settle into that 1,500rpm by itself, other times it won't. But it always does if I raise my speed to 63mph/rpm to 1,900. Then when going uphill it'll settle back to 1,500 and I can drop my cruise back to 60 and that's where it'll stay.
I'm just wondering, if that is indeed the converter locking up, then why has no other vehicle I've ever owned done this? It's like it gets confused. I don't like the fact that unless I raise the speed 3mph it'll stay up at 1,700 for a whole trip. That 200rpm in fact does affect my mpg over longer rides so yes it does kinda concern me that I have to consciously make an effort to get it to lock.
It's done it since day one too so it's nothing new.
I'm interested to hear some takes on it.
2011 1500 5.7/5 spd.
When on the highway @ 60mph on cruise, flat terrain the engine settles in at 1,700rpm.
If I bump the cruise up 3 times to 63mph the rpms will rise to a 1,900 spike then drop to 1,500rpm where it will stay for the remainder of my trip.
Now here's where my curiosity kicks in as I'm not a stranger to auto trans or converters. I'm not a know-nothing novice, but I'm not familiar with this particular behavior.
Sometimes if I achieve 60mph and set my cruise on a slight downhill grade it'll settle into that 1,500rpm by itself, other times it won't. But it always does if I raise my speed to 63mph/rpm to 1,900. Then when going uphill it'll settle back to 1,500 and I can drop my cruise back to 60 and that's where it'll stay.
I'm just wondering, if that is indeed the converter locking up, then why has no other vehicle I've ever owned done this? It's like it gets confused. I don't like the fact that unless I raise the speed 3mph it'll stay up at 1,700 for a whole trip. That 200rpm in fact does affect my mpg over longer rides so yes it does kinda concern me that I have to consciously make an effort to get it to lock.
It's done it since day one too so it's nothing new.
I'm interested to hear some takes on it.
