rocker arm torque spec issues 2010 gmc sierra 5.3 vortec

Rivera_6 · November 17, 2017

so I went in order of torque spec by doing 22 ft lbs on exhaust and intake valves of coarse on 2,4,6,and 8. I would torque intake rocker arms when I had exhaust valve just starting to open and exhaust valves when intake valves were just starting to close. this was done with the engine under the hood, wiring all in tact, ect, ect... Now... after doing this torque spec than firing the truck and ran rough as hell until I back off the bolts, than everything sound fine after that. I than proceeded to snug the bolts back up gently before putting the valve cover back up. No tick no nothing. test drove it about half a mile. loud as hell tick and misfire coming from cylinder two. where is the middle ground here because 22 ft lbs seems to be too much and getting it snugged up enough to where it sounds normal at idle doesn't seem to cut it either.

Please I need help.

redvett · November 17, 2017

What M&Y? "LT" engines need valves lashed and "LS" just torqued down to 22 ftlbs with no lash. Anyone that has loose rockers must be tightened down further.

SierraHD17 · November 17, 2017

Rockers on an LS are non adjustable... torque them to spec to keep them tight on the tray in the head. If you need to leave them loose the pushrod length is wrong and hanging the valves open thus you need a shorter pushrod.