The Energon Pub

Does anyone know the anime/manga this image comes from??

I don't speak japanese so it's difficult to search for any info about it...
Thanks in advance.

Yeap! You are right!
And to be more specific this is:
http://gaogaigar.wikia.com/wiki/Brave_Command_Dagwon
which is some kind of sequel(if I got it right)to the one you suggested.

Thanks a lot!!

It's not a sequel per se, as all 7 to 8 Yuusha/Brave series are stand-alone. I find Dagwon a bit odd in some aspects I must confess, and it's not how the heroes are Sentai/Power Ranger like or magically "become" the robots like in Masterforce. The whole just feels half-baked.

When I was 10 years old I went to Japan with my parents for some kind of business trip.One day we went to a toy store and some cool TF-like robots grabbed my attention and my mother bought for me a transforming airplane accompanied by a transforming police car,an ambulance and a fire truck which all combined into a huge robot.I also got a small book(the cover of the book is the image I posted earlier)about the series these toys came from.
Today,almost 15 years after that day,I found the figures and the book inside a box I had almost forgot it existed.I was looking for any english word that could help me identify it,but nothing(not even the ISBN helped me)...
But then..some fellow transforming-robots-fans helped me learn some things about these great toys from childhood...
Thank you guys!
I was wondering if this anime is worth-watching but GoldRabbit's comment about "half-baked" discouraged me a bit...

I just recently (like two or three months ago) became knowledgable of the Yuusha/Brave Series. As was already stated, they are not sequels as they are their own separate continuities from each other. These series were developed through Sunrise and Takara and there are a number of robots that are re-designs of Transformers' characters. For example, in Brave Exkaiser, the first series, the main antagonists are the Geists and four of the five Geists are re-designs of Slag, Sludge, Snarl, and Swoop. Gaogaigar, the last of the series, is the best of them!