I have a 2004 gmc with an lm7 5.3, I have read a few different places that GM switched to the ls6 pump in 2003 for all truck motors, is this true? I'm almost ready to do my head/cam swap and if this is the case I'm not going to replace the pump. I have about 90,000 miles on the truck which I bought new and has always had Mobil 1 ran in it.

 

well if you always had good oil pressure then i dont see why you should change it .... gm oil pumps have always been good .... but if you had low oil psi and want a very high flow high psi pump ... get the LSA pump that comes in the cadillac cts-v ... those are the best pumps money can buy.... very high psi and flow.... because the lsa engine has oil squirters and those need a very high volume of oil to maintain oil psi....

 

It's been my understanding that all of the GENIII LS engines used the same oil pump, from the 4.8, to the LS6. Pretty sure that if you cross reference the PN's for a 99 4.8 and LS6 oil pump they will be the same.

 

^ Hes right. You have to get to an exotic engine like the LSA etc for a different PN to pop up

Some benefits can be had from a light port job and shimming the bypass spring some to boost pressure, otherwise dont mess with it

 

O.k. Thanks guys

 

SDPC has ported oil pumps that should fix you up!

LS6 Oil Pump Kits In stock and ready to ship. $72.95 + S/H

We also have Blueprinted & Ported oil pumps as well.

SD3946B Ported LS Oil Pump $149.75 + S/H

SD1830C Ported/Coated LS Oil Pump $196.80 + S/H

Ported Pumps are in stock, and coated should be ready in a couple of weeks!