New valve cover gasket and gromets still leaks

I put a new OEM gasket on my 98 tacoma 2.7. Valve cover was leaking in same area before the change. Leaks in the back corner on passenger side. I used new gromets and torqued down to correct torque value. I still have a leak in the back passenger corner. Bad enough that I smell it on my exhaust. The way I understand the gasket expands in channel to seal off valve cover when tightening down. Tightening down past torque value does no good from what I have read. Any valve covers gasket bigger or work better than OEM.

 

For my old 3VZ-E, I made new valve cover bolt hole sleeves on the lathe that are 0.3 mm shorter than O.E. which range in height from 12.10 to 12.15 mm. With M6 x 1.0 valve cover bolts, that results in about 100 degrees more bolt rotation (0.3 mm more valve cover gasket squish). I checked the valve covers prior with a straight edge and they're good. The roads are very salty right now so I won't know how this will hold up in the long term but it's leak free so far.

 

My 08 2tr 2.7 was leaking in the same spot after doing the valve cover gasket and continues to leak after pulling everything off and retorquing everything very carefully. I'm thinknig a little rtv along the sides that lead to the lower corner might be the ticket. The only downside is that it might not be reusable after adding rtv, but for $25 bucks for a new one, not having to spend time to redo it another time is potentially worth it.

 

Another thing is, despite me being a cheerleader for original parts, I ditched the black, made-in-Japan valve cover gaskets for the blue Fel-Pro replacements. They have a wide, ribbed base and are chubbier overall. I don't care, these are a PITA to change and I did not want to do it a third time!

 

I have heard the felpro was a good replacement. I will check my valve cover while its off the truck for warpage.