This has happened to me twice now, so there's something to it.
Jeep 4.0 I-6, 232,000 miles. Great compression, moderate rear main drip, just basically a mildly greasy motor. Valv HM has reduced oil consumption greatly over past 3000 miles at valve seals.
OK. first OCI was Valv HM 10/30. Much louder valve racket than when I brought it home (wondered what they'd used?). Added VI thickener due to 1 qt/wk consumption. Noise quieted a little (say 15%). As it continued needing oil, I added some leftover syntec xw20. cut the noise in half (hmm weight, add pack, or vi?); the engine didn't feel as isolated from the car...could feel more things moving; made sense with thinner oil.
As I was using a strong dose of seafoam, changed at 1500 miles. Lots 'o junk came out. The ADB on the filter was shot. Sparkly oil (carbon flakes?) oozed from the filter. yea.
My rear main leak is now half of what it was.
NEXT OC: valv HM 10w40 w/ PL3001 filter (bigger!) & moderate seafoam (1/2 can into ~7 qts oil). ALMOST as noisey as the 10w30! Added 1 qt 20w50, again, maybe quieted by 10%, or less. Oil consumption now is like 1qt/3wks, but the weather gets cold and in these colder temps the pressure stays way high all day. 1 qt top-off with Castrol HM 10w30. A little quieter, and happier (slightly) pressure.
Here's the kicker...added 1 qt PP xw20 last night. started car. at 15 seconds of hot idle, the noise just...went away. cut in half or less.
My Theory 1: Sticky lifters may have a "ridge" of varnish-- thinner oil gets in there better and plunger slides over the ridge. BUT, if this were true then it would have been quieter with 10/30 than 10/40. Blows that theory.
My Theory 2: Valv HM is not ideal formulation for this motor in terms of noise. Said b/c every time I've added something else, gets quieter. Ok...maybe.
My Theory 3: Something in the syn, or the syn that doesn't contain something else bonded to it, is lubricating stuck parts better. maybe.
What do YOU think??? I've never seen this... Would like to find a more optimal oil next OC!!
Mike
Jeep 4.0 I-6, 232,000 miles. Great compression, moderate rear main drip, just basically a mildly greasy motor. Valv HM has reduced oil consumption greatly over past 3000 miles at valve seals.
OK. first OCI was Valv HM 10/30. Much louder valve racket than when I brought it home (wondered what they'd used?). Added VI thickener due to 1 qt/wk consumption. Noise quieted a little (say 15%). As it continued needing oil, I added some leftover syntec xw20. cut the noise in half (hmm weight, add pack, or vi?); the engine didn't feel as isolated from the car...could feel more things moving; made sense with thinner oil.
As I was using a strong dose of seafoam, changed at 1500 miles. Lots 'o junk came out. The ADB on the filter was shot. Sparkly oil (carbon flakes?) oozed from the filter. yea.
My rear main leak is now half of what it was.
NEXT OC: valv HM 10w40 w/ PL3001 filter (bigger!) & moderate seafoam (1/2 can into ~7 qts oil). ALMOST as noisey as the 10w30! Added 1 qt 20w50, again, maybe quieted by 10%, or less. Oil consumption now is like 1qt/3wks, but the weather gets cold and in these colder temps the pressure stays way high all day. 1 qt top-off with Castrol HM 10w30. A little quieter, and happier (slightly) pressure.
Here's the kicker...added 1 qt PP xw20 last night. started car. at 15 seconds of hot idle, the noise just...went away. cut in half or less.
My Theory 1: Sticky lifters may have a "ridge" of varnish-- thinner oil gets in there better and plunger slides over the ridge. BUT, if this were true then it would have been quieter with 10/30 than 10/40. Blows that theory.
My Theory 2: Valv HM is not ideal formulation for this motor in terms of noise. Said b/c every time I've added something else, gets quieter. Ok...maybe.
My Theory 3: Something in the syn, or the syn that doesn't contain something else bonded to it, is lubricating stuck parts better. maybe.
What do YOU think??? I've never seen this... Would like to find a more optimal oil next OC!!
Mike
