I've got what I believe to be a stuck lifter making noise, so I've decided to change them. My question though is about preloading the lifters. I read a how to on preloading them, but its taking measurements to the hundrethd of an inch. Now, my ruler doesn't have that kindof accuracy, and guys I know that used to work on old-school engines back in the 70's said if I'm using OEM lifters, rockers, and pushrods, then as long as I torque my rocker arm bolts to spec then the lifters will be preloaded properly, is this true or does pre-load need to be checked whenever changing lifters, pushrods, springs, rockers ect.?

 

You need to measure the required pushrod length when the combo is back together to ensure you get the correct length. Depending on what the lifter is and how much preload it requires, you could need a shorter or longer length. Check with the manufacturer on whatever lifter you purchase as to what their recommended preload is. That way once you use a pushrod length checker to get the length at zero lash, you simply add the require preload and you have the pushrod length you need to purchase.

Jon

 

I'm just going to purchase the OEM lifters though to replace my old ones, so shouldnt the OEM pushrods be the correct length and it all just work?

 

You should be all set if everything is stock. Just bolt the rockers using the GM procedure.