Greguw

Does anyone know if a 24 valve vacuum pump will work on a 12 valve . I have one off a 1999 with the pump thats connected ... I need the Hydro return port for my truck .
I have both versions but have not pull anything apart yet ...
The 24 pump looks to have a longer front shaft and may come close to the timing cover .

I guess I will answer my own question ... I pulled off the original 1996 one , the newer 24 valve fits great , good gear mesh . Had to remove the return throttle spring bracket and required a little trimming due to the larger steering pump ... little knotch and it was fine .
Also have to extend the oil feed line .
I did not have to change the power steering feed line ... This 12 valve is going in a cheby ... Had the power steer line and it was the same .