I have a '99 gmc Safari van. I had to replace a leaking badly radiator. After replacing it I found the battery drained. So I charged it completely and it tests ok. However it will turn over fine but it just won't start. Seems weird because I drove it fine down to the maintenance shed.

SOURCE: 1998 gmc safari van

Check your spark plugs. That could be one of the reasons. Or are you sure you purchased the proper Fuel pump?

SOURCE: GMC Safari Van - Change spark plugs

i went under for driver side then i took off passenger side wheel you also have to remove two bolts that are holding dipstick tube in place it is easy to get them from the wheel well on passenger

SOURCE: I need to find and change the fuel pump relay on my 1993 GMC Safari. Any help?

I don't have the whole solution, but I do know that my fuel pump is in side the gas tank on my GMC Safari. Hope that helps!

SOURCE: 2000 GMC Safari Overheating

double check the pump the impeller inside can be rotted away and it will still pump some but not enough to cool it at 65 mph , you can remove the pump and take off the plate on the back and look at it easily? second get a tech to loan you his infared thermometer and double check the temp it can pinpoint the problem ? good luck [email protected]

SOURCE: 1999 GMC safari AWD mini van hub /bearing

try this link:
http://www.edmunds.com/used/1999/gmc/safari/11196/specs.html