Some of you may say a stupid question we'll see

Im thinking of trying out a bit of a diy diff cooler for the esco's as its gonna get some abuse on the track this year and im now on my 3rd diff since christmas

My question is this I take it you need a pump to draw the oil out of the diff and thru the cooler then back in to the diff ( Would a normal external fuel pump sufice this job or would it clog up with the viscossisty of the oil)

Any input greatfully recieved

Regards Doug.