Tom and Ray retract: some cruise control systems DO have the ability to slow a car going down hills.

Dear Car Talk | Apr 01, 2002
Dear Tom and Ray:
TOM: Look, Ed. If you want to call our advice into question, you'll have to get in line -- and the line currently stretches to somewhere in the Pennsylvania mountains.
RAY: I have to give credit to my brother. He told me that he thought "some car" he had driven had downshifted under cruise control to slow the car. I told him he had his headlight in his taillight socket (which is usually a good bet). But it turns out he was right.
TOM: We got letters from hundreds of Chrysler minivan owners who told us the same story you did, Ed. So we called Chrysler, and you're absolutely right. They have a system that can downshift to slow a car.
RAY: Most cruise-control systems (let me save a little face here) do operate only the throttle. But this one -- and there might be others out there by now -- can also operate the car's electronically controlled transmission (automatic only, of course). So if you exceed the cruise-control setting by a lot, it can shift the transmission into a lower gear and use the engine's natural braking power to slow you down.
TOM: So we'd like to apologize to fathers-in-law everywhere and give a belated dope slap to the son-in-law from the original letter who doubted the old man. And one for my brother for doubting me, too.
TOM: Look, Ed. If you want to call our advice into question, you'll have to get in line -- and the line currently stretches to somewhere in the Pennsylvania mountains.
RAY: I have to give credit to my brother. He told me that he thought "some car" he had driven had downshifted under cruise control to slow the car. I told him he had his headlight in his taillight socket (which is usually a good bet). But it turns out he was right.
TOM: We got letters from hundreds of Chrysler minivan owners who told us the same story you did, Ed. So we called Chrysler, and you're absolutely right. They have a system that can downshift to slow a car.
RAY: Most cruise-control systems (let me save a little face here) do operate only the throttle. But this one -- and there might be others out there by now -- can also operate the car's electronically controlled transmission (automatic only, of course). So if you exceed the cruise-control setting by a lot, it can shift the transmission into a lower gear and use the engine's natural braking power to slow you down.
TOM: So we'd like to apologize to fathers-in-law everywhere and give a belated dope slap to the son-in-law from the original letter who doubted the old man. And one for my brother for doubting me, too.
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