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Rolling car

when car(automatic) is stopped in traffic on hill(car facing up hill) if i take my foot off the brake car rolls back…is the transmission not engaged…starting to slip or something else?thanks

Condition and level of the transmission fluid? New symptom or has it always been this way? Is the car new to you or have you had it for years?

fluid level ok…new symptom ~2 weeks…used to me 8 months

How many miles does the car have? How steep is the hill?

Most newer cars with automatics will roll back under these conditions. It’s not unusual.

Any automatic will roll back if the hill is steep enough.
Learn the stickshift younucklehead. ;o)

This is perfectly normal, especially with new cars.

The engine is connected to the tranny via a fluid coupling device called a “torque converter”. It’s sort of like a hollowed out bagel cut in half with vanes inside each half, and filled with fluid. As the front half spins, it drags the fluid and the fluid drags the back half. When sitting idling, there’s not enough drag created by the fluid to pull the back half with it. That’s why the engine can keep idling while the drivetrain stays idle.

In new cars, the design has evolved to almost totally disconnect the halves of the torque converter at idle, the goal being to eliminate all load on the engine and increase gas mileage a bit. In short, the car becomes “free rolling”, totally disconnected from the engine. If you’re on a hill facing up, it’ll roll backwards.

2003 ford focus wagon ~35000m(didn’t get driven much) ~45deg hill…by other posts seems like it’s normal so will just have to like it…thanks

45deg? 100% gradient?!? Any thing that wasn’t bolted down would simply slide off a slope like that…or require in excess of 1G coefficient of friction to stay.

A 38% gradient (Canton Ave in pittsburgh…worst of the “dirty dozen” hills) is really, really steep.