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1677-HO 1999-2004 Chevy GMC AM Gen 6.5L Diesel CCW threaded fan clutch water pump

$253.98

1677-HO 1999-2004 Chevy GMC AM Gen 6.5L Diesel CCW threaded fan clutch water pump

$253.98

The 1677-HO is designed to outperform GM's higher flow rate "130 gpm" pump introduced in 1997 with the threaded hub. GM achieved higher flow rates with a 10% larger impeller diameter than the earlier versions.  Most people simply look for that to determine if it it is higher output or not.  We go a wee bit further.

Our impeller outperforms and outflows to help the 6.5L diesel run a little cooler under a load.  The impeller has an increased vane count, a reduced impeller vane clearance to the casting volute and a ported shroud to build pressure in the eye and an appropriate B gap clearance to limit the potential of pressure pulsation or hydraulic shock

It achieves greater flow rates, higher head pressure and a more efficient flow. The impeller color is due to Type II Class II military grade surface coating which protects against corrosive fluids. 

FlowKooler introduced the first hi flow pumps and continues to improve impeller design. Why is increased flow so important to cooling a hot Chevy diesel engine? Because, it has been proven time and time again that reducing the cycle time between the heat source and the heat sink, creates more opportunities to shed heat and drop engine temperatures.

From 0-3,300 RPM…Nothing Beats a FlowKooler!

General Specifications:
Type of Material of Pump Body Cast Iron
Number of Blades on Impeller 10 CNC Aluminum
Direction of Rotation CCW
Fan Hub  threaded
Hose Connections: 1st 2nd
Gender F F
Diameter 3/4" 11 o'clock NA
Threaded No  NA
Other Special Features:
  • CNC Machined Aluminum impeller with 10 vanes
  • Protected with a Type II Military grade anodized surface coating
  • 1999-2004 6.5L Diesel with screw on shaft
  • This has one hose connection and space to drill and tap a second
  • Alternative Part Numbers 12456231, 12555711, 12555752, 12569281, 19168609, 50745093, 5745093, 88894035, 44056  
  • M1097A2, M997A2, M1035A2, M1045A2, M1043A2, M1025A2, M1123, M1113, M1114, M1152 etc.
Parts Contained in Box:

Mounting Gaskets, Installation Sheet, FlowKooler Decal

Make Model Year CID Liters
CHEVROLET C1500 SUBURBAN 1999 395 6.5L
CHEVROLET C2500 1999-2000 395 6.5L
CHEVROLET C2500 SUBURBAN 1999 395 6.5L
CHEVROLET C3500 1998-2000 395 6.5L
CHEVROLET C3500HD 1999-2002 395 6.5L
CHEVROLET K1500 SUBURBAN 1999 395 6.5L
CHEVROLET K2500 1999-2000 395 6.5L
CHEVROLET K2500 SUBURBAN 1999 395 6.5L
CHEVROLET K3500 1999-2000 395 6.5L
GMC C1500 SUBURBAN 1999 395 6.5L
GMC C2500 1999-2000 395 6.5L
GMC C2500 SUBURBAN 1999 395 6.5L
GMC C3500 1999-2000 395 6.5L
GMC C3500HD 1999-2002 395 6.5L
GMC K1500 SUBURBAN 1999 395 6.5L
GMC K2500 1999-2000 395 6.5L
GMC K2500 SUBURBAN 1999 395 6.5L
GMC K3500 1999-2000 395 6.5L
GMC SAVANA 2500 1999-2000 395 6.5L
GMC SAVANA 3500 1999-2000 395 6.5L
WORKHORSE FASTRACK FT1801 2002-2005 395 6.5L
WORKHORSE FASTRACK FT1802 2002-2003 395 6.5L
WORKHORSE P32 1999-2003 395 6.5L
WORKHORSE P42 1999-2005 395 6.5L
WORKHORSE W42 2004 395 6.5L
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