I have a Cat C15 and a E-F 9 speed Top 2 trans.

I don't do lugging as that spikes my exhaust temps and melts the turbocharger.

What happens is this: I'm cruising at 65 in nine @ 1400rpm. I hit a long hill and the rpms drop even with the cruise trying to compensate. When I get down to 1150 rpm, the trans automatically goes to 8. I hate that. Mostly because I should shift to 7 when I hit 1100 or so. Eighth gear is a formality but once in a while it's all I need to get over a hill.

Anyway, that's all the automatic there is...the rest is all on me and I've had to go down as far as 5 @ 1500 to get a heavy trailer up a steep hill, such as Donner Pass or Cabbage Hill. Poking along at 25 mph in the far right lane is hard but I've learned to get along over there since I also have a neutered truck.

Brian

Post #16 is why I love the cellar.

What? That was standard trucker talk. We always mention rpms along with the gear when discussing our trucks since it is possible to do, say, 55 in gears 7-8-9 with different rpm ranges depending on personal preference/load demands. When I'm light or empty, I usually go for high gears and low rpms but the opposite if heavy or going uphill.

Kids these days don't know how to drive stick. :-)

In the Cardinal, I cruise at 2,000 ft MSL at 2,200 rpm and 23"hg manifold pressure. :-) To climb, it's "25 squared": 2,500rpm and 25"hg.

Takeoff power is "balls to the wall" though...never know when you might need a little extra.

See that is what I mean, on the cellar you don't have to contend with the blank looks, and the rest of us can read and learn!

I mean it, that's why I love it here.

That and the sarcasm. <––– being sincere there.

I'm not going to say a word.http://www.cellar.org/images/smilies/rolleyes.gif

I would never use cruise control in rain. I also understand about downshifting and getting out of cruise constrol on steep grades. I just wondered if the cruise control wouldn't turn itself off in the situation described in the OP. I guess not if the car has an automatic transmission.

I actually use cruise control when I want to pay MORE attention to my driving, not less. I'll put it on when going down a stretch of the interstate, especially after dark, where I don't have to be glancing down and checking my speedometer for my lead foot tendencies and can instead concentrate on the road.

The Pueblo-Walsenburg stretch of I-25 is annoying because the change in grade is gradual but steady. The first couple of times I drove it in my current car, it seemed like I should be able to make it in 5th gear just fine, but the laws of gravity and a four cylinder engine would always catch up with me near the exit for the bustling metropolis of Rye. I have resigned my self to just down shifting to 4th (and out of cruise control) when I reach a certain spot near the beginning of the long, slow climb.

It'll slow down real fast when you hit the telephone pole.

I meant to say cruise control. :redface: Cruise control uses the driveshaft speed whereas traction control uses wheel speed..... and most people don't have that anyway.

I forgot the link
 

Here is the link for how a cruise control works.