Per p. 170 of the Owner's Manual:I have a 2018 JLU 2.0T with automatic transmission. I have noticed lately while on cruise control let’s say 30mph, when I get on a downhills my rpm’s will shoot all the way from 1600 to 4500 and will engine brake hard.
It just started doing that a few weeks ago.
Using Cruise Control On Hills
The transmission may downshift on hills to
maintain the vehicle set speed.
The Cruise Control system maintains speed up
and down hills. A slight speed change on
moderate hills is normal.
On steep hills, a greater speed loss or gain may
occur so it may be preferable to drive without
This is worth an exam by the dealer.