400k Mile 2UZ-What oil would you use? (1 Viewer)

[odonekanobe]

Came across a great deal on a 411k 1999 Cruiser. Bone stock, runs great. Needs some attention like timing belt, suspension, interior cleaning, etc.

I've always used synthetic oils on my vehicles but never had one with this high of mileage and don't want to mess up a good thing. As far as I can tell it was pretty much the quick oil change places used in the past, judging by the windshield sticker.

I've heard/read things about when you switch to high-mileage oil that you better stick to it, so I thought I would poll the group and see what everyone thinks. Thanks for the help!

 

[newbielx470]

I'm curious about a somewhat related question. Do we have to stick to the high-mileage synthetic (e.g. Mobil 1 Extended Performance for 20k miles interval) forever after using it for a while?

----Edited: Sorry I confused the "high-mileage" vs. "extended-interval". I meant to ask if we once used the Mobil 1 "Extended-Performance"/"Annual-Protection" synthetic oil which claim to be good for 20k-mile interval or one year, do we have to stick to it forever?

 

[nissanh]

I'm curious about that too. Do we have to stick to the high-mileage synthetic (e.g. Mobile 1 Extended Performance for 20k miles interval) forever after using it for a while?

unless you have an oil leak at an O-ring or burning oil excessivly, there is no need to go with thicker oils. you can do what the specification says: if it asks for 5W-30, then go with it, you can bump upto 10W-30 but no more than that. Thicker oils take time to flow. Do you see any drop in the oil pressure gauge? Does it stays low or 1/4 at all rpms?

5000 miles or once a year is what I call an interval. Avoid high mileage oils.

 

[Rhetoric]

What you have read is correct. And @2001LC has expressed this in many threads.

I would not run high mileage motor oil in a 2uz (or any motor I cared about). If you have leaks: fix them, or run some AT-205 reseal through it to slow anything down.

 

[JunkCrzr89]

switch to high-mileage oil

DO NOT USE HM OIL!!!!!! IT WILL DESTROY THE SEALS AND YOU WILL HAVE LEAKS EVERYWHERE.

 

[Josie'sLandCruiser]

I have been doing 10,000 mile engine oil changes with Mobil 1 synthetic 5W30 and OE Toyota filters in my 2007 Tacoma with the 4.0L V-6. Started at 80,000 miles and now almost 180,000 miles. Get positive test results from Blackstone Labs when I send samples every 20 - 30,000 miles.

My UZJ100 I bought in June 2019. The previous owner (for at least 10 years) had run Mobil 1 5W30 synthetic engine oil so I continued this, but have switched to the 5W30 synthetic "high mileage" version (current mileage is around 340,000.) I follow the same 10,000 mile oil/filter change regime.

 

[odonekanobe]

After reading what I have on here, I am pretty sure I am going to stay away from the high mileage oils.

But if this motor has only run standard oil for 400k miles, would switching to a Mobil 1 synthetic (standard, not HM) be asking for leaks/problems?

 

[Bisho]

Do you know what oil the PO was getting at the quick change places? It wouldn't surprise me that they were upselling him on high mileage oil for a while. You may be committed.

I would try whatever oil suits you (I use Pennzoil ultra premium) with AT-205 on the first change, then see what happens. If it leaks like a sieve you can always go back to the high mileage oil. If it doesn't, you can use what you please.

BTW, Mobil 1 is not the best stuff anymore. Most scientifically based reviews put it in the bottom half of what's available. It used to be the cats meow (except in aircraft engines, where it killed motors), but it stood still on its name and reputation while others moved ahead.

 

[Patassa]

After reading what I have on here, I am pretty sure I am going to stay away from the high mileage oils.

But if this motor has only run standard oil for 400k miles, would switching to a Mobil 1 synthetic (standard, not HM) be asking for leaks/problems?

Shouldn't cause any issues. I switched to synthetic after 15 years or so, never been a problem.

 

[odonekanobe]

Do you know what oil the PO was getting at the quick change places? It wouldn't surprise me that they were upselling him on high mileage oil for a while. You may be committed.

I would try whatever oil suits you (I use Pennzoil ultra premium) with AT-205 on the first change, then see what happens. If it leaks like a sieve you can always go back to the high mileage oil. If it doesn't, you can use what you please.

BTW, Mobil 1 is not the best stuff anymore. Most scientifically based reviews put it in the bottom half of what's available. It used to be the cats meow (except in aircraft engines, where it killed motors), but it stood still on its name and reputation while others moved ahead.

The Jiffy Lube sticker only says the date and mileage, nothing else unfortunately.

Do you run a full bottle of AT-205?

That's a bummer to hear about Mobil 1. I have a lot of it stocked up.

 

[Rhetoric]

BTW, Mobil 1 is not the best stuff anymore. Most scientifically based reviews put it in the bottom half of what's available. It used to be the cats meow (except in aircraft engines, where it killed motors), but it stood still on its name and reputation while others moved ahead.

Can you share more than an anecdote? There are also as many flavors of Mobil 1 as Baskin Robbins has ice cream.

I'm not a Mobil 1 advocate here, but that's a pretty broad statement.

Oils work very differently in each engine type. Maybe Mobil 1 5w30 EP is meh in a GM 406 small block, but it works wonders in a GM 2.0 LTG... for example.

OP: Just keep oil in the 2UZ. Switching to synthetic from conventional is sort of an old man's fear mongering tale told at the auto parts store.

For reference: I run Mobil 1 5w30 EP in both my 2UZ and 2.0LTG, mostly because I'm lazy and want to only stock one oil for two engines. The LX had only dealership services done its whole life with "Valvoline 5w30" so whatever the dealer bulk is... switching to the M1 hasn't changed a thing for me and I switched at 225k miles. Currently have 246k on the truck.

 

[jsloden]

450k miles regular mobil 1 5w30, NOT HIGH MILEAGE and a toyota filter. Every 10k miles. No leaks, no sludge. Used Mobil 1 in over 50 different vehicles. Never had a problem with it.

 

[Bisho]

Can you share more than an anecdote? There are also as many flavors of Mobil 1 as Baskin Robbins has ice cream.

I'm not a Mobil 1 advocate here, but that's a pretty broad statement.

Oils work very differently in each engine type. Maybe Mobil 1 5w30 EP is meh in a GM 406 small block, but it works wonders in a GM 2.0 LTG... for example.

OP: Just keep oil in the 2UZ. Switching to synthetic from conventional is sort of an old man's fear mongering tale told at the auto parts store.

For reference: I run Mobil 1 5w30 EP in both my 2UZ and 2.0LTG, mostly because I'm lazy and want to only stock one oil for two engines. The LX had only dealership services done its whole life with "Valvoline 5w30" so whatever the dealer bulk is... switching to the M1 hasn't changed a thing for me and I switched at 225k miles. Currently have 246k on the truck.

Look at Project Farm on youtube. Very well done testing and analysis. There are others as well.

I'm not saying Mobil one is bad, there just are better oils for the money today. My favorite was Rotella gas truck, but unfortunately it was discontinued. I did use Mobil 1 during the Covid supply pinch.

 

[Bisho]

The Jiffy Lube sticker only says the date and mileage, nothing else unfortunately.

Do you run a full bottle of AT-205?

That's a bummer to hear about Mobil 1. I have a lot of it stocked up.

AT-205 is a ratio of the total volume. I don't recall at the moment.

 

[2001LC]

I have been doing 10,000 mile engine oil changes with Mobil 1 synthetic 5W30 and OE Toyota filters n my 2007 Tacoma with the 4.0L V-6. Started at 80,000 miles and almost 100,000 miles past now. Get positive test results from Blackstone Labs when I send samples every 20 - 30,000 miles.

My UZJ100 I bought in June 2019. The previous owner (for at least 10 years) had run Mobil 1 5W30 synthetic engine oil so I continued this, but have switched to the 5W30 synthetic "high mileage" version (current mileage is around 340,000.) I follow the same 10,000 mile oil/filter change regime.

Mobil I states: If high mileage use for 2 oil changes, must then use thereafter for life of engine. Meaning your engine is addicted to HM oil. Stop using and you will leak at every rubber seal.

"High Mileage" oil is poor label/term. We think: Yeah I've high mileage, must be good for my engine. NOT!
It should say: Warning used is intended for engines, with excessive oil leaks. "Mileage" has nothing to do with it's use.

 

[99lc100]

Mobil I states: If high mileage use for 2 oil changes, must then use thereafter for life of engine. Meaning your engine is addicted to HM oil. Stop using and you will leak at every rubber seal.

"High Mileage" oil is poor label/term. We think: Yeah I've high mileage, must be good for my engine. NOT!
It should say: Warning used is intended for engines, with excessive oil leaks. "Mileage" has nothing to do with it's use.

I recently started changing my own oil and of course I have now done two oil changes with Mobil 1 Synthetic High Mileage oil. Since I started using it I noticed a small leak at the bell housing which I assume is the rear main seal. I've had people recommend switching back to traditional oil from synthetic. Anyone have any proof of Mobil 1's statement above? I don't want to switch back and encounter more leaks.

 

[DuckLN]

op - when you joined 10 years ago what vehicle were you driving?

 

[2001LC]

I recently started changing my own oil and of course I have now done two oil changes with Mobil 1 Synthetic High Mileage oil. Since I started using it I noticed a small leak at the bell housing which I assume is the rear main seal. I've had people recommend switching back to traditional oil from synthetic. Anyone have any proof of Mobil 1's statement above? I don't want to switch back and encounter more leaks.

Call Mobil One tech support. Ask them for your prof. They said to me: After 2 oil changes with HM oil, you must use for life!
HM (High Mileage) oil. Has petroleum base seal modifiers. This swells seals while in use. They'll eventual shrink and harden. The end result is rubber seals fail.

I'd flush oil with 2 cans BG EPR and then change oil filter. Add 10 oz of AT-205 to fresh 7qts M1 5W-30 and filter It helps make leaks manageable.

 

[99lc100]

I'd flush oil with 2 cans BG EPR and then change oil filter. Add 10 oz of AT-205 to fresh 7qts M1 5W-30 and filter It helps make leaks manageable.

Thank you sir, I will give that a try. By "flush" do you simply mean add the BG EPR to my current oil and then do an oil change?

 

[2001LC]

Thank you sir, I will give that a try. By "flush" do you simply mean add the BG EPR to my current oil and then do an oil change?

Yes! Add 2 cans to warm engine old oil and run 20 to 30 minutes. You can just drive around, but best you do not shut off engine. Drain within 1 hour of engine off, the sooner the better. Use care as oil is very hot. Let drain at least 1 hour or longer, with drain plug out.