Originally Posted By: Rhymingmechanic
Is there any benefit to using the newer pump? The older style pump and t-stat/housing are still available.
Thanks
Good question! I have a '01 Silverado and my G/F has a '02 GM Sierra, both with 5.3 engines. Both are in great shape without any signs of a water pump problem.
I think the two styles would preform the same, but the cost may differ on what style you choose- keeping your old thermostat and pulley if applicable.
If I may approach this from another direction, the only negative thing on an 99-03 style water pump is that your choice of a new (not rebuilt) replacement would have to come from AutoZone (Duralast) or Kragen O'Reilly (Cardone), unless you can find new old stock OEM or an AC Delco. A new "one size fits all" style (99-06) from AutoZone will probably cost a little less then a AC Delco pump from a Distributor.
If I recall correctly and I'll stand corrected if I'm wrong, Gates manufactures AC Delco and some NAPA water pumps. The choice there would be either a Gates, NAPA, or AC Delco water pump. Those pumps will definitely be the updated 99-06 style. That seems to be the direction I would go even though a thermostat would be an additional purchase and no looking back.