3/8" to 1/2" hyd. hose OK?

I had a 3/8" swing cylinder hose bust so I got replacements for both of the lines as both had friction wear....

They did not have 3/8" hose so I went with 1/2". It is working well but now I have a leak on one of the swing cylinder seals. Could that larger hose be putting more pressure on the cylinders? Hoses are only approx. 40" long. Also I have been doing a lot of ditch cleaning using the swing cylinders pretty hard.

Thanks

3/8" to 1/2" hyd. hose OK?