How long should a water pump last?

A little over two years ago my original water pump started leaking out the weep hole. (not long before this I had done a complete flush and refill of the cooling system). I replaced the water pump with a brand new cardone with a lifetime warranty. I re-used the coolant as it was practically new and a couple months later added a coolant filter. Over the last month I noticed my coolant level going down very slowly but couldn't find any leaks. Today I noticed it is leaking from the weep hole. I dont really mind because I should be able to get a free replacement but It seems like two years is a very short life especially considering I had a coolant filter for 1.5 of the 2 years.
Is there anything i might have forgotten or done wrong that could have caused this? Maybe some WPs just last longer than others... idk.

On a side note. Since I will be dropping the coolant I figured i would go ahead and do a flush and refill with new. I know International says not to run extended life coolant because of our copper injector cups but does anybody know why? The website for Final Charge Global (which is what i'd like to use) specifically says it is ok to use with copper. If I dont end up running the ELC what conventional coolants do you guys recommend?
Thanks-

 

You need to find something that already has SCA's in it or you need to buy the supplemental additive that helps prevent cavitation.

There are several coolants out there that work. Many use CAT ELC or Zerex G5. You can get the red stuff at Wal Mart called Global Extended I believe.

 

Farm, have you heard of anyone having problems with injector cups or anything else because they were running red coolant?

 

if its just comming out of the weep hole very little and have no huge puddles on the ground then your prob burning up coolant. you could have a bad sleeve. FYI the injector sleeves are brass not copper.
alot of guys run cat ext. life coolant. but be sure to put in the proper additives.
Mitch

 

79f-250 I am pretty sure that my coolant loss is only from the water pump. Also it is my understanding that ELCs do not require any additives except the extender at 3 yrs/300,000 miles or whatever. At least this is the case with the few ELCs i have looked into.