I got my H3 In the last week of November (26th) And to the day I have 1800mi on it and have not changed the oil on it. The way i'm going its going to be close to a year before I "need"to change the oil. The dealer told me at 5000 change itand to use regular oil syn. is not needed. I know there is a topic going on now about kinds of syn. to use but is it that much better or a waste as my dealer told me.Soquestions.
1. When to do first change?
2. What to use reg or syn. ?

 

https://www.hummerforums.com/m_28941/tm.htm

this covers everything u asked about
i found it using the search

 

Thanks. Just tring to bringsome life to this place today..

 

ur welcome

 

I Just did mine this morning for the 1st time- 3,589miles - I had the dealership put in synthetic (They used Mobil One) for $72. I didn't receive any notice from OnStar that it needed to be done but I wanted to be on the safe side with my brand new H3

 

I changed my oil soon after the break in period, to rid of all those assembly lubes from factory, and of any heavy metal particles existing at the bottomof the oil pan and filter!!!
Ran Dino oil for another 1000 miles... to make sure all of the remaining metals floating around the Engine has passed through, then i changed the Oilusing Amsoil 5-30 with Amsoil oil filter, and i change it two or three times a year depending on how my rig is driven during that period!!!