People were already using synthetic oil for 50 years. All Amsoil did was say, "hey, let's stick this stuff in a car". Wow... amazing breakthrough.

I don't need an oil analysis to know that my truck starts and runs, has Castrol GTX in it and has 456,000 miles on it. It's had nothing but GTX since new (along with, oh my gosh, Fram filters). Oh, and 90% of those miles were delivering newspapers and phone books, so it's constantly stopping and going.

 

I'm going to take a guess that your truck is a nissan 720, isn't it? Yeah, those things are damn near indestructible.
Edit Just read your sig, yes it is. I used to have an '84, amazing little truck. Took out all the tpi parts, installed a weber carb, ran great.

For everyone's consideration, it's a possibility that the engine design is also a factor in the lifespan of an engine with a given oil. Between different oil pressures, pumps, temperatures, and wear surfaces, it may play a role.

 

Mine's a D21 with the VG30i engine... Your '84 was a 720.

 

Ah, yours was a hardbody. Great trucks either way.

To try and re-rail the thread I'm interested in hearing what everyone has to say about viscosity, what's everyone's favorite? Hell, we've gotten down to 0w-20 these days so it's quite a variety.

What viscosity oil do you use in your car?

 

The truck gets 10/30 in the Winter and 20/50 in the Summer. The Mustang gets 5/20 since that's what Ford says to use.

 

I'm using Shell Helix Ultra 10w-40 oil troughout the year. Which ss recommended for cars which are about 10 years old. Honestly have no idea what's the best oil for my 98 Tiburon with 163*** Km's on it.
Anyone suggestions? I'm goint to change the oilfilter next month so...

 

Pick a good brand and call it a decision. I use Mobil 1 synthetic and Purolator Pure One or OEM filters. Changing it regularly is going to be about as important as the brand name, as long as it's not the cheapest 1/3 of whatever's on the shelf. If you *really* can't make up your mind, I'm sure the dealership would like to sell you some of theirs . . .

 

heres the secret, okay theres alot of debate about whats better synthetic or regular
hands down synthetic 5w30 w/ mystery oil additive, works.

But for complete honesty to everyone in the thread, regular non synthetic oil would really be best for a high mileage engine.