I know some guys has changed to the electric fan.
http://www.youtube.com/watch?v=zzTDar1QDCg
i know your from norway and trying to help, but your not helping.
why do you think your radiator is going out? i only replaced mine because a huge crack busted in the plastic part while i was driving down the beach.
stock radiators are MORE than capable enough of cooling. what the other guy was probably trying to say is that your money is better spent on upgrading the fans to electric fans, if you don't already have them from the factory (all 05+ will have them from the factory. the 05+ efans can be swapped into 00-04 models with a harness and special tune to activate the ecm pins to enable the fans).
all tahoes/suburbans already come with the 34" radiator, which is the bigger one that GM offers (other size is 28"). stick with a/c delco to be safe. rock auto has it for 171$ plus shipping (AC Delco part number 21650) i usually google part numbers and see where i can get the best price.