Engines over 150k miles suggestions?

I was always "told" that only newer motors should have synthetic oils put into them.. That being said for higher mileage motors what do you use?

I just got my taco a week or so ago and wanted to change the oil.. the previous owner said he had syntheic oil in it... my last few cars which have been brand new mind you i have put mobil1 synthetic oil in them...

What do you suggest?

Convetional oil
"Syntec" oil
High Mileage oil (per labeled at your auto part store)
Full Synthetic

 

Mobil 1 and keep what you've been using as far as the Synthetic part goes.

 

I would continue putting mobile 1 synthetic in, if the origional owner had been running that through the engine for a while.

 

He didnt say what he was using... nor any weight references, he just noted synthetic oil and he only owned the truck for less then a year according to carfax...

 

YOU ARE FINE USING SYNTHETIC ANY TIME IN THE LIFE OF THE ENGINE.
I just switched at 158,000 and haven't had a single leak or burned any in the 600 or so miles i've driven with it. Just put in a name brand synthetic (l like pennzoil platinum) and be done with it.

 

Whoever told you that is wrong. It is a part of an old myth.

Myth: Mobil 1 will leak out of the seals of older cars.
Reality: Mobil 1 does not cause leaks. In fact, new Mobil 1 was tested in dozens of industry standard and original equipment manufacturers (OEMs) tests to prove its seal performance. It is fully compatible with the elastomeric materials from which all automotive seals and gaskets are made. If an older engine is in good condition and does not have oil leaks, Mobil 1 provides the same advantages as when used in a new engine. ExxonMobil recommends taking measures to repair the leaks, then using Mobil 1. ExxonMobil also recommends following the automobile manufacturer's manual for the proper oil to use. Also watch our answer; it's myth four of five in our online video.

http://www.mobiloil.com/USA-English/MotorOil/Synthetics/Myths.aspx

This is true. No need to flush, no special filter. Just drain and refill with synthetic and you're good to go.

 

Mobil 1

 

Interesting. I was under the impression that the issue sometimes encountered in older engines was that the cleaning agents in a synthetic would remove deposits that had been preventing an existing oil leak.

 

It's NOT necessarily a myth.....

Vehicles that have been on conventional (non synthetic) oils for all their lives - if you switch to synthetics at higher mileages, you CAN have issues develope. Some can have issues while others might not have any issues. It all depends on the condition of the vehicle at the time of switching. And this isn't necessarily related to Mobile 1. It can happen with any synthetic oil.

I bought a tacoma with 60K miles on it. I put synthetic oil in (Mobile 1). It started 'oozing' at the oil pan and I consumed 1/2 quart of oil every 4,000 miles. I bought a Jeep Wrangler with 80K miles on it. I put synthetic oil in it (Mobile 1) and I developed a lifter tap that was pronounced at startup but eventually quieted at the engine warmed (never leaked anywhere). None of these issues were bad enough to seek further troubleshooting. It's just something that developed that I 'kept an eye on' in case they got worse. Over 5 years of owning these two vehicles, that's the extent of the issues I had and they stayed the same over those 5 years.

Synthetic oils penetrate further than conventional oils and they also 'cleanse' better than conventional oils. So YES, there is a posibility that things can happen after switching - but I don't believe they're bad enough to 'not' switch to synthetics at higher mileages.

 

keep using synthetic oil.it cant hurt it

 

Mobil 1, religiously (imho).

 

i have 200,000 miles on mine and i put whatever's on sale at autozone in mine. 5 quarts plus an oil filter 20 bucks im on it and no leaks at all.. its all a bunch of bull shee change it and it will still run great

 

I had 265000 on my first Tacoma (95). Conventional oil changed between 5 and 7 thousand mile intervals

 

I bought a 98 2.7 this past winter from the original owner, it had 185k miles. I changed the oil to full synthetic drove 400 miles and developed rod knock, was it from the oil or not, I dont know but could only assume..

 

most likely not. I think it would have done it sooner if it was because of the oil. Im not sure though.

 

300K on my old 93 Toyota V6 and I put the cheapest regular oil I could find in it and it NEVER burned any oil and never had any issue's. I don't run synthetics and really probably never will.

 

Not really synthetics don't burn like regular oils. They don't really thicken up as oil changes approach like regular oil. When i do changes my synthetic is pretty much the same color as i poured in and regular oil looks black. No thanks I'll pay that slight bit extra. If you use regular oil in the engine for long periods of time then switch you will always have dark colored oil on changes because the deposits are all over the place from running regular. The synthetic constantly keeps loosening it up and you see dark synthetic on changes, still slippery than hell though even when used. You think that's normal but it's not. A engine run always on synthetic does not really get darker in color as it's been used. Slightly maybe but never black.

The key is though regularly change the oil. What convinced me and why I'll never go back to regular. Changed my oil on my bike and I spilled the old oil all over the place. Was walking in it for hours on the shop floor. Put in new synthetic and spilled a few drops. I accidentally stepped on those drops a few minuets later and fell on my ass. Started up the bike and it was half the volume in engine noise. That's got to be good for a engine. The other place you notice synthetic performance is in the winter on cold weather starts. It's simply better oil.

 

The reason the regular oil is black is because it holds the products of combustion in the oil. That is a good thing. If the oil came out clean where did the products of combustion go? It's still in the engine. There was an aviation test a couple years back and they proved this. They ran two air cooled engines, one on synthetic and one on regular oil. The regular oil came out black and the synth came out clean. When they tore down both engines, the one with synth was loaded with sludge and the regular oil engine was not. I'll try and find the article.

 

According to a Assie that makes special filters the black is actually from water and acids in the oil from moisture and a regular filter is not designed to remove it. He makes a filter that removes it. Think I can find the damn link? It's called a Mil mac filter but can't find the web site. Google is having a brain fart.

My fall on my ass was my Eureka moment.

Any equipment that I've ever worked on, million plus dollar equipment, generators and compressors they only use synthetic.

Generators I've taken apart that only ever run synthetic don't have those deposits you speak of.

http://www.mail-archive.com/sustainablelorgbiofuel@sustainablelists.org/msg05499.html

"The chemical compounds in engine oils break down over time due to prolonged exposure to high temperatures and poor maintenance habits. When the oil oxidizes, the additives separate from the oil and begin to chemically break down and solidify, leading to the baked-on oil deposits turning gelatinous, and that nasty compound is what is lovingly referred to nowadays as sludge. It's like black yoghurt. What doesn't help is that modern engines, due to packaging, have smaller sumps than in the "good old days" and so hold less oil. This means that the oil that is present in the engine can't hold as much crap (for want of a better word) and can lead to earlier chemical breakdown.
The most common factor in sludge buildup is mineral oils combined with a lack of maintenance by the car owner combined with harsh driving conditions."

The black is not combustion products well maybe the oil burning up and thickening up. Combustion products of the oil, not the fuel.
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Amsoil is great regardless of mileage.