Milankovitch cycles do affect climate on Earth. There are several cycles. 

> "Variations in [eccentricity][1], [axial tilt][2], and [precession][3] of the Earth's
> orbit resulted in cyclical variation in the solar radiation reaching
> the Earth, and that this orbital forcing strongly influenced climatic
> patterns on Earth."
> source: [wikipedia][4]

Scientists of Pleistocene's climate evolution strongly correlate Milankovitch cycles with glacial/interglacial periods, affecting the Gulf Stream Current.  
Other factors of Earth's internal system, such as volcanic events do affect climate, but changes in the magnitude of solar radiation are a well known climatic variability generator.


  [1]: https://en.wikipedia.org/wiki/Orbital_eccentricity
  [2]: https://en.wikipedia.org/wiki/Axial_tilt
  [3]: https://en.wikipedia.org/wiki/Precession
  [4]: https://en.wikipedia.org/wiki/Milankovitch_cycles