I searched around the forum and could not find much on people running synthetic motor oil. I normally run Penzoil or Valvoline 10w-30 in my 02 3.4L. I saw the Royal Purple thread and it got me thinking about switching to synthetic oil. I remember my auto shop teacher in high school saying something about if you switch to synthetic oil you should not go back to non-synthetic oil.

So who runs synthetic motor oil?

 

I do. I run Castrol Syntec 0W-30. My 4 runner seems to like it.

Beware though, that the chances of it leaking around the valve cover gasket and/or rear main seal is increased greatly.

 

I use the amsoil 10w40.Its made for the flat tappet cams.
http://www.amsoil.com/storefront/amo.aspx

 

https://www.yotatech.com/forums/f116...-10w30-159736/

Check out this thread bro.

 

I'm running chevron synthetic. It really cleaned the sludge up well

 

I run Mobil 1 extended performance 5w-30 and I haven't seen any leaks and the engine runs smooth. You CAN switch back to castor oil after successfully switching to a full syn. oil but it wont do you any good and you will loose all of the benefits of synthetic. You do want to be carefull however switching frome a castor oil to a synthetic because synth. has a bunch of detergents in the mix that clear deposits. That's all in good except when those deposits are what's helping to keep the oil in! Esspecially in older rigs that have been on castor oil for most of their life, you might as well just stick with the castor. If you're already running synthetic and you don't have any issues, you can switch between brands as you please because just about all synthetics are running similar detergents and it shouldn't hurt the engine if you switch once in a while. Hope it helps!

 

Synthetic is better in every way over dino oil. I see no reason to run dyno other then new engine break in (only because it is slightly cheaper).

Personally i am a big fan of the 5w-40 rotella T6, you can get it at walmart and it is some very good stuff.

AMSoil is also very good but more expensive.

 

Maybe this is obvious to some but why would this be? I am not running synthetic on a 200,000 mile engine but would make the switch but not if its going to cause more problems because of the high miles

 

Thanks for the help. Its nice to see someone from my old neck of the woods. I really miss that place. I grew up in Placerville.

 

I run the amsoil 10w40 in the 3.0 4runner brcause its the only oil, even over the Mobil 1,that will bring up the oil pressure and hold viscosity better than anything I've tried.
I've used mobil 1 for years,being our family was the Mobil distributor in the Richmond area for 30 plus years.Amazing results with mobil 1.
Mobil, amsoil,or any other synthetic is a good choice. People say dont change from regular to synthetic in high milage vehicles,I do it all the time with no issues.

 

I switched to Shell T6 5W40 synthetic at 109K on my 1990 22RE and now, at 138K miles no leaks or problems whatsoever.

 

I use mobil 1, I switched from conventional oil at 90,000 miles. Now at 126,000, I have a little leakage around the valve covers, I'm pretty particular but it dosn;t bother me. There is no rear main leakage on my 4runner.

I use the mobil 1 becasue it is thinner and circualates at startup better than conventional oil.

 

i use Red Line 15W40 Diesel. I get better fuel mileage by about 2km/liter compared to Mobil Delvac1

 

I use Mobil 1 10W30, it's cheaper if you buy it at walmart.

 

Royal purple 5w 30 for a couple thousand miles. really makes a difference. I drove 1200 miles straight and My engine performed flawless and never got hot

 

Ran Royal Purple in my 89 4runner for a while (well over 200,000 on the engine when I did it) and it promptly started leaking from the rear main. I had to go back to dino oil at the next oil change. I did notice the engine running better after the synthetic "treatment" and it still runs as good now. I'm still running synthetic in the tranny and t-case since they don't leak..... yet.

 

This can happen on really old engines. The synthetic oil will clean the motor out real good and sometimes it cleans away sludge that was stopping oil leaks.

I personally like to know my engine is nice and clean inside though. If you really want to clean the motor out good get some mobile 1, it is not that good as a synthetic oil but it is very good at cleaning out the motor. It is actually the treatment of choice in some TSB's.

I have seen a motor before/after 2 oil changes with mobile 1 and it really did a good job cleaning it up. the oil was DIRTY from all the stuff it cleaned out in 2500k miles.

 

X2 an a hardened old seal will leak eventually anyways. That's why when I worked in a shop we'd offer rear main seal replacement for cost of parts when we pulled a trans for anything.

 

I run AMSOIL in everything in my 92 4wd P/U. I plow in the winter and off road in the summer and have never had a problem. I also use OE Toyota filter from the dealer for like 4.00$$$ and it is a Toyota part how much better can you get.

P.S. Never run anything other then OE Toyota fuel filter on any Toyota. Save yourself plugged fuel injector problems.

 

I started running castrol syn 10w-30 in my truck after my new head and cam broke in and never had a prob with it and i have recently switched to royal purple 20w-50 for this summer and plan on going with the royal purple 10w30 for the winter. I havent had any leaks on the motor as of right now. In my opinion the royal purple seems to make my motor run smoother or atleast sound like its running smoother LOL. And yes its expensive around 8 sumthing a quart but imo you get what cha pay for thats also my reason for running oem toyota parts except the preformance stuff