Educate Me | Regular Syn vs High Mileage

[Ronin73]

Hello! Just curious about something. I see many threads on high mileage syn and regular syn, but I don't really understand why one would pick high mileage. Could you educate me on the scenarios?

For instance: If I use Mobile 1 EP 0w20 on my car from mile number 1 new and perform regular changes and all other appropriate maintenance, then why would I switch from using it to Mobile 1 High Mileage after 70,000 miles? Thanks for the knowledge!

 

[AutoMechanic]

Usually if your cars engine seals are getting weak or breaking down you would use high mileage to help swell them back up. You would know they were getting bad if you seen a lot of smoke on start up. The high mileage is also supposed to have better detergents in it to fight sludge.

 

[wpod]

For instance: If I use Mobile 1 EP 0w20 on my car from mile number 1 new and perform regular changes and all other appropriate maintenance, then why would I switch from using it to Mobile 1 High Mileage after 70,000 miles? Thanks for the knowledge!

I would say you answered your own question.

 

[PimTac]

Hello! Just curious about something. I see many threads on high mileage syn and regular syn, but I don't really understand why one would pick high mileage. Could you educate me on the scenarios?

For instance: If I use Mobile 1 EP 0w20 on my car from mile number 1 new and perform regular changes and all other appropriate maintenance, then why would I switch from using it to Mobile 1 High Mileage after 70,000 miles? Thanks for the knowledge!

There is no reason to switch from MOBIL to high mileage unless you have a need to do so like a leaking seal or seals. Just keep running the EP 0w20 until that day comes, if it ever does.

This idea of switching at 75k is mainly marketing.

 

[PimTac]

I should also add, that since I started driving in the 70’s with multiple vehicles over the years, I have never used a HM oil. If I had the situation where a engine started to consume oil my first response would be to go up one grade.

Today’s engines don’t have all the gaskets and such like the old days. Beads of sealant have replaced many of those and HM oil will have no effect on sealant.

 

[ka9mnx]

I should also add, that since I started driving in the 70’s with multiple vehicles over the years, I have never used a HM oil. If I had the situation where a engine started to consume oil my first response would be to go up one grade.

Today’s engines don’t have all the gaskets and such like the old days. Beads of sealant have replaced many of those and HM oil will have no effect on sealant.

Agree but I have had HM oils stop seeping oil seals, for good, on my old junks.

 

[Crash Bandicoot]

Curious about this as well, my understanding is they contain seal swellers and are on the thicker edge of grade when looking at cSt they also supposedly have an additive package that is beneficial for older engines which sounds more like marketing unless you’ve got engine oil leaks. For consumption and no leaks I’d bump up a grade on normal. Seen plenty 300k+ engines on here who have had a steady diet of normal synthetic their whole lives and look clean enough to eat off of.

I also wonder if that 70,000 miles is a holdover from the days of yore when a car was basically trash at 100,000 miles. 70k is barely broken in, you’re only 10k from the first trans service in many cases.

 

[kschachn]

After "can I use 5W-20 instead of 0W-20?" and is "20W oil just for CAFE?", this is probably the third or fourth most discussed topic here. Maybe look around a bit and see if your question is answered. It's been talked about a lot. You've been on here over a year and a half I'm surprised you haven't seen those threads.

 

[ka9mnx]

They ARE NOT seal swellers. They are seal conditioners and all formulated engine oils have them.

 

[BlueOvalFitter]

Hello! Just curious about something. I see many threads on high mileage syn and regular syn, but I don't really understand why one would pick high mileage. Could you educate me on the scenarios?

For instance: If I use Mobile 1 EP 0w20 on my car from mile number 1 new and perform regular changes and all other appropriate maintenance, then why would I switch from using it to Mobile 1 High Mileage after 70,000 miles? Thanks for the knowledge!

Ask ALL the Q?'s you want! That's what the members are here to do, help out other members. Don't let some here deter you.

 

[RazorsEdge]

Ask ALL the Q?'s you want! That's what the members are here to do, help out other members. Don't let some here deter you.

Ask away, that is the purpose of the forums.
The members who are here only to be a pain,add them to the ignore Somebody just got added yesterday.

 

[SR5]

I have never used a HM oil. If I had the situation where a engine started to consume oil my first response would be to go up one grade.

Today’s engines don’t have all the gaskets and such like the old days. Beads of sealant have replaced many of those and HM oil will have no effect on sealant.

Same here mate, I have never purchased HM oil, and even though Australia has a strong car & oil culture, High Mileage oil is one of the few oils that you don’t much see around. Not a strong call for it here, from what I can tell.

You keep going with your regular oil if that is working for you, and if your engine gets a bit tired and starts consuming oil then you step it up a viscosity grade. Usually keeping to the same brand, eg M1 0W20 to M1 5W30

 

[Ronin73]

Thank you very much for the information!

 

[JohnnyJohnson]

I should also add, that since I started driving in the 70’s with multiple vehicles over the years, I have never used a HM oil. If I had the situation where a engine started to consume oil my first response would be to go up one grade.

Today’s engines don’t have all the gaskets and such like the old days. Beads of sealant have replaced many of those and HM oil will have no effect on sealant.

Very true PimTac but it may affect you wallet. Yes the last HM I ran in the Corolla was Pennzoil HM 5w-20. It was on sale at WM for $14 something a Jug but they had a rebate running so it came down to $4 and change. Seems I find HM oils on sale at times the regular band isn't same with 10w-30.

 

[SR5]

Very true PimTac but it may affect you wallet. Yes the last HM I ran in the Corolla was Pennzoil HM 5w-20. It was on sale at WM for $14 something a Jug but they had a rebate running so it came down to $4 and change. Seems I find HM oils on sale at times the regular band isn't same with 10w-30.

Yes, if you get a HM oil on sale at a decent price and it’s the correct grade & specs, then fill ‘ya boots.

Also some of the M1 HM oils are quite thick and carry the Euro A3 spec, I see these as closet performance oils for those who don’t need extra ZDDP but want to run a name brand synthetic.

 

[mahanddeem]

Also some HM oils are "thicker" than their "brother" oils

 

[slimjim2525]

I put a HM oil in my old 2007 GMC Sierra with 5.3 when it hit 100k miles. It really did not run smooth at all. I dumped it at 700 miles and went back to ST 5W30.

 

[JohnnyJohnson]

When you can get the HM on sale with a rebate for $4 a jug you get it. My Toyota never knew the difference!

 

[BLND1]

I generally use HM oils for vehicles over 10 years or 100k miles.

A little thicker, a little more robust add pack... why not.

 

[PandaBear]

Based on the UOA I have seen they are usually thicker (because some of them burn oil), with more seal conditioner (because some of them burn oil), with more detergent (because they likely have more carbon build up at the ring pack, and out of warranty so emission system poisoning lawsuit threat is less likely), and slightly less fuel efficient if the engine didn't blow by or burn oil (thicker, to compensate for ring pack carbon build up and oil leak through seals, takes more energy to pump thicker oil, etc).

If you don't care as much about fuel efficiency they are actually a good oil to use on newer car too.