gunluvS14

that's crap about high mileage engine doesn't like synthetic oil. Synthetic oil behave like regular dino oil except it provides more stable dynamic viscosity under high temperature. The difference between brand name is the additives they added into the oil, nothing fancy or magical about it.

For high mileage engine that has slightly worn out main and rod bearings(bigger clearance), you can use thicker viscosity oil to bump up the oil pressure, that will help maintain proper oil pressure at high load/high rpm, especially for a tired oil pump. Not to mention, some high mileage specific synthetic oil has gasket conditioner to help to soften up the aged harden seals to prevent oil leak

Lucky Devin

I had been putting Mobile 1 Super Synthetic in my car for the last 20k miles. My ride has 139k on it right now. I thought I was doing good...

So would it be best to switch back to non-synthetics?

gunluvS14

no dude.. its fine.

Lucky Devin

Thanks, I figured that was the case. I just couldn't think of a plausable reason that synthetic oils would be [i]bad[/] for a high mileage 1UZ.

3000

They also have high mileage Mobil 1.

FormosaSC

i dont think switching back to crap-oil from synthetic is a good idea....

Fireblaze

I previously used royal purple, but switched to Mobile one because the RP was getting too expensive....

Luke_in_SD

hey guys I've have been using Castrol GTX 10w-30 and my car has about 122,000 miles. Do you guys think I should switch to 5w-30, might help MPG????

GS4VIPbOSS

iTrader: (9)

So I want to thank SC drifta -took your advice and bought some Moble 1 5w-30 from walmart for 21.99. Changed the oil myself and it now feels very nice indeed. I noticed a smoothness in initial acceleration. I did some seafoam prior to the oil change but not so sure of it's real impact. The Mobil 1 does make a difference. The car feels more like a lexus-very smooth- I have not had any notable issues all others considered I would reccomend the synthetic over dino and Mobil 1 if going that route.

Luke_in_SD

thats good, but is 5w-30 recommended over 10w-30?

StiCk3

iTrader: (5)

it says 5w30 on the oil cap...

either way the car would be fine i dont know bout the mileage...

RxG300

my 1992 SC300 has 186000 on it... im thinking about using Q horsepower on my next oil change... can i do that without any problems?

Luke_in_SD

do any of you guys ever put in any additives to the oil????

xknowonex

iTrader: (2)

I use 10-30 Mobile 1 High Mileage Synthetic on my car with 176,000 miles and everything is fine. It was leaking oil before I switched over from dinosaur oil but its not a big deal

breakb

iTrader: (2)

at the moment i'm still using w/e oil was in the car when i bought um. on my next one though...gonna switch to mobil 1 synthetic.

Peace out