94 4runner opinions on 5w30 syn or 5w40syn?
 

I have a 94 4runner 241K on the clock, runs good has a very mild idle stutter, but otherwise runs well. Oil was changed by PO using 10w30 conventional. We have 9 vehicles in our family, so i buy 5w30 full syn costco and 5w-40 T6 for my diesels i buy both oils in bulk. The 4runner is the oldest vehicle i own. Anyways anyone use either of these weights? any issues? good, bad, opinions? I know the manual says 10w-30 but i just want to continue buying in bulk. I live in NM, mild winters and over 100F summers. This 4runner is just my around town and to work truck that i use to do nothing more than to put miles on. I know 5w30 and 10w30 are the same viscosity at operating temp, but at start up the 5w is thinner and flows better, is that a good thing? also hasn't oil come a long way since 94? did they even have synthetic lol. Any info would be appreciated.

With the high mileage, you should think about 20w50. I have a 1988 with the 22RE. As expected, it burns some oil as many high mileage, older engines do. As per my mechanic's instructions, I run 20w50 in it. I trust him...he built the motor currently in it back in 2005.

I run delo400 in my truck.

Dump that rotella in and keep on truckin. Thats good stuff.

I'm an AMSOIL guy. Run 5w30 in both 3VZEs and in my 3RZ. No wear or sludge issues when I popped off my valve covers. Lot of good oil out there.

I have a 1994 with a 22RE, 331K on it so far, no sign of stopping anytime soon. Burns a half a quart every two weeks I would estimate, and it leaks some also. Use good quality conventional oil for 5,000 mile intervals.
Older engines are looser built than newer designs. They really like the higher, thicker weights. I've run 20W-50 often in the summer since it thins out badly in 100 degree plus. Completely agree with the earlier post, he has an old school knowledgeable mechanic.
I run 10W-40 during the winter and nothing thinner. Using the high mileage versions can't hurt, ever other oil change I try to use that type.
My 2018 TLX ASpec car is 0W-20 full synthetic and that is water viscosity when I change that oil, scares me to think that is what is stopping metal on metal, but the newer engines want the water oil. Newer engines have much better tolerances and build quality, thin works in a tighter tolerance engine.
I ran full synthetic in my BMW in the 90's, it was so expensive back then, I remember it well every time I would change it.
Just my two cents from my 14 years with my 22RE 5speed.

I have run T4 (5gal bucket tractor supply) or T6 (when on sale), can’t go wrong with either. I also run T4 in all my 20 yr old Honda ATVs, no friction modifiers to mess with the wet clutch. Been using the diesel oil in everything but modern vehicles like my wife’s CRV for decades.
Check out “Project Farm” on utube, he does film strength, heat resistance and longevity testing in many episodes with a lot of oil brands and types.
I also have a 04 Cummins.

I have a 1994 4Runner and I use conventional 10w30 Valvoline VR1. I think a very thick oil, it is not good for cold starting, which is where there is more wear.

A very thick oil also takes longer to lubricate the engine galleries. Very thick is also more difficult to dissolve the bubbles that may form, etc.

20w50 is a pretty thick oil.

Before using 20w50, I prefer to use 5w40 or 10w40.

Check out “Project Farm” on utube, he does a test comparison between Delo and Rotella.
Film strength
Heat breakdown
Cold flow
And more.

cool video, thanks for the share. . wow that delo didnt do so well lol.

The difference is really minimal in the big picture, but the “T”s were impressive. That guy does some cool evaluations.