Is Truganina a safe place to live?

Have lived in the place for almost 5 years, and have had no issues. Neighbours are quite friendly too, we say hi every time we bump into them. :)

Hi , can anyone suggest me If I open an Indian restaurant in Truganina industrial area , will it run well ?

Last 2 years. The place is really safe compared to many other places in Melbourne.
No issues at all. North of Truganina is better .

We are a retired couple, planning to downsize and thinking of living in Truganina... maybe get a house and land package. Any suggestions which area, streets would be preferable if selecting an established house?

All of these people will tell you its safe because they want to keep their house prices up. The raw data does not lie, and you can make your decision using it:
From Last Year:
Total crimes are up 26% out of which Robbery is up 290%
Drug Offense is up 33%

You can look this data up yourself here:
https://www.crimestatistics.vic.gov.au/explore-crime-by-location

I see gangs all the time

Don't expect a real answer here. When you need real evidence for crime rates, you go to the source.

https://www.crimestatistics.vic.gov.au/

https://www.racv.com.au/in-your-home/home-advice/burglary-statistics.html

Yes, living in area for last 5 years..... no issues. In fact, many developments happened in past few months which makes entire suburb worth living :)