Mobil1 0w40 or Mobil 1 HM for valve seal leak

[Jeffy_D]

Like a good BITOGGER I googled old posts about valve stem seals. It seems that maxlife is recomended, but I cant seem to find maxlife full syn in my area.

So im leaning toward M1hm 5w30 due to winter coming up. But I also read posts about group 5 Esters swelling up valve seals.... So mobil1 0w40 came to minde as being the thickest pao easily available. If I cant swell the seal shut, then at least maybe the thicker oil wont seep past the seals.

Any insight appreciated.

This regarding my lebaron

 

[LeakySeals]

I've had no luck swelling valve seals with any oil. Maybe they get too burnt up, too warn, or HM oils have no effect on viton rubber. Good luck with valve cover and oil pan leaks using M1 HM 5w30. In hot summer months I add/top off with a quart of M1 HM 10w40.

 

[Hermann]

The Maxlife full syn in 10w-30 or 5w-30 is available on Amazon but expensive. About 50% more than Mobil 1 High Milage at WalMart in 5qt jugs.

 

[mechtech2]

Jeff -
You seem to be on the right track.
All you can do it give it a try, but don't hope for miracles.
Thicker oil always attenuates leaks and burning. the additives may help, and may not.

 

[dan3952]

I got new valve stem seals, and a new valve cover gasket ($720), and the car still burns oil, but probably reduced 40%. I feel that if too much oil is getting down the valve guides due to excessive clearances, then there is nowhere for it to go and it will burn no matter what. I did notice that it does burn less with the thicker oils in the 10W30 grade, and I get less smoke on start up (a better film that doesn't let as much down the engine block when the car is at idle or shut off?). My engine does not like 40 grade oils, the valvetrain made all sorts of noises. If you can get Mobil 1 HM I would use that in the recommended grade, it is thicker than standard Mobil 1 (Note that 10W30 is still good down to -18 deg C, and that you could use a block or oil pan heater). If you must get esters you could try blending with Redline or Royal Purple. There's also Liqui Moly Motor Oil Saver (had it in last oil change, not sure if it helped me or not)