2003 Grand Cherokee 4.0 Litre

[erh54]

A relative of mine has had several issues with:
1. A/C fails to cool one day then the next day cools fine.
2. Transmission seems to slip from time to time.
3. Has seen smoke ( maybe steam ) appear from under hood.
Has been to dealer 3 times, and no problems have been found. Has anyone heard of this before or had these problems? Number 3 is really strange to me.