Application for #3964255 Oil Pump

[Larry H.]

Does anyone know the application for oil pump #3964255? This part number was superceded by #3969870 in November, 1979. #3969870 is listed as an oil pump for a 1969 ZL-1. What did the 33964255 fit? Any help would be appreciated.

Thanks,

Larry

[Joe L.]

Re: Application for #3964255 Oil Pump

Larry-----

GM #3964255 was a SERVICE-only, heavy duty, high volume big block oil pump available from late 1969 until November 1979. The pick-up screen which was part of this oil pump assembly may have been positioned lower than the screen attached to the GM #3969870. As far as I can tell, this pump was never used for any PRODUCTION engine assembly and I don't think that it was ever used for any SERVICE (crate) engine assembly, but it's possible that it was used for the latter.

[Clem Z.]

Re: Application for #3964255 Oil Pump

we ran those pumps in race engines back in the 60s and the pan that was used was from a heavy duty truck which held 6 quarts . the pickup screens were welded to the pump.

[Larry H.]

Re: Application for #3964255 Oil Pump

Joe, I had hoped that my question would bring an answer from you. Thanks for the application info. And Clem, thanks for your response as well. Before I posted this question I checked the archives for any previous references to this part number and found your April, 2001 answer to a question where you discussed using the #3964255 oil pump with a 6 qt. truck oil pan on race engines in the '60s.

Thanks again,

Larry