If HT06 were that much better, Honda would have gone back to it with their new turbo motors. They haven't, they just use the API specs these days.I am just running into this as well with HTO-06
I've been digging and digging and I think this thread has INCORRECT information.
I cannot find any specification that superseds the HTO-06. One person is correct in that it was GF5 testing plus the hot tube test on used oil. But without that part of the test it's not superseding HTO-06 and apparently it's hard to pass or is cost prohibitive.
I will give some case in point examples that apply to me and this thread.
First it is important to understand that I have not found any oils that are not 5w30 that bear HTO-06 certification.
Secondly when one is found like Mobil 1 or Pennzoil Platinum, if you actually look you'll find that it's high mileage brother does NOT bear the HTO-06 certification. But yet they have the other certifications including GF-6. So I don't think GF-6 oils surpass or supersede HTO-06 like SP does to SN.
I don't know if it's just cost prohibitive for a certification that applies to few turbo cars that is probably not even considered by many drivers, or if there is something in the high mileage add pack that causes it to fail the test?
I'd sure like to know because I for one already made this mistake and didn't catch it until I the first time I pulled the dipstick and checked the oil level and saw it was already as dark as it is by the drain interval. I started head scratching wondering what the heck changed so I went comparing bottles I keep to carry my used oil away and noticed I had just assumed the high mileage version had the certification since the regular did. Doesn't seem to be the case.
I can tell you from a simple internet search that Castrol Edge, Castrol Edge EP and Mobil 1 EP specifically state HTO-06 on their Product Data Sheets.
An oil doesn't cause a 30% decrease in mileage. Especially that oil. You are looking at the wrong thing.Im wondering about all this now. I did my oil change and had Ultra Platinum 5/30 put in. Nothing else was really done. Now Im losing 30 percent of my gas mileage, as a short drive I can physically see the gas needle go down. I dont know what else to check, or what else may be causing this other than the oil itself.
I noticed that 5W-30, Mobil 1 Extended Performance and Valvoline Extended Protection have the DEXOS1 Gen. 3 cert. But Mobil 1 Extended Performance High Mileage and Valvoline Extended Protection High Mileage don't have the DEXOS1 Gen. 3 cert. Anyone know why this is?Thanks to everyone who responded to me.
Where I got tripped up on the HTO-06 is the fact some still spec it but those brands high mileage oils do not bear the HTO-06 certification.
In the end I was trying to swell up a little o-ring to stop an oil drip until warmer weather. The mobil 1 HM did nothing. I was going to call Pennzoil and Valvoline, but I saw the little turbo logo on the Pennzoil website and was like ehh it probably is as good as HTO-06 they just don't pay for the certification on the high mileage oils. So I used the Platinum HM.
It's still in it, still looks good, and stopped or slowed the drip. I decided to just contact Pennzoil and ask them about this because I might just keep using it.