Can I replace 245/40/18 tyres wit 245/45/18 on E61

[Kumar 1]

My current tyres on E61 are 245/40/18 Run Flat and its about time to replace them. Can I replace them with a different size like 245/45/18 tyres ? The rims are standard BMW 18" alloy wheel, M double spoke 135. 
8Jx18 EH2 IS20 

I believe the wheel part number is : BMW 36 11 8 036 947 (same as 36 11 8 036 570) 

[qube 3570]

i suggest to stay with 245 40 18. This is not a rare tyre size, no reason to go for bigger as it has a bigger rolling diameter compared to the original size and will throw off your speed on the dash.