trying to get a costco battery but the interstate external link get routed to point to H48, which is a whopping 1.2" longer than H47.
Wondering if the H48 dimension is an error, seems like other members used H47 without any fitment issues.

 

I believe what you are looking at is this:
https://costco.interstatebatteries.c...697&Country=US
I have already installed and there is no issue on fitment. The battery tray on the R55 is large enough to handle it.

 

Thanks for confirming and saving me from Shelling out extra $ buying an AGM battery!

 

I got the Ac Delco Size 48 AGM battery and it fit albeit with a little elbow grease. Worked like a charm since install. The 3 year warranty was nice as well.