MB1 10-30,in summer and 5-30 in winter. Changed about every 3-4k depending on how nasty it gets.

 

I use Mobil 1 synthetic 5W30 and change it around 5k. The computer has barked at me twice when I let it go longer, both times were around 7500

 

I usually just go by the computer. But, last time I got it tuned it reset and I let it go for 8500 miles. Ooops. But hey, as long as there was still some in there, that's all I care about. I use 15w40 dino.

 

Royal Purple 10w30 normally every 3k..but i'm thinking i'm gonna start goin every 5k now.

 

i use syn. in my 2006 lbz and change it at 3500-4000

 

I run conventional Castrol GTX 5W-30 and change it every 3,000. Mobil 1 went through the valve seals on my 1978 Z28. The engine only had 5,000 miles too. I lost respect for synthetic after that.

 

Ouch, i didnt know that Synthectics would go through seals???
Unless you had a Seal failure??

But im using Mobil 1 5w30 w/ Wix filter.. (got the PN in my truck, but to lazy to go get it)
Roughly bout $31 per change When ever the Light tells me. bout 4500-5k miles?

its been using some oil lately
Maybe i need to stop running her so hard?

Anyway its passed my bed time...
Later,
Jonathan

 

You know your supposed to let the engine break in before useing sysn in a motor.Back then you shoudn't have even tried to run it before 6k....

 

Synthetic lubricants definately have their advantages over there conventional counterparts. Synthetic contain base stocks and additive packages that are more durable then what is used in conventionals. Because of this they resist shearing, oxidation, break down, and other negative effects by controling heat better.

Changing synthetic at 3-5000 miles is simply a waste of good oil, time, and money. The GM oil change light was engineered to suggest oil changes using conventional oil that met specifications at that time. This oil change light has no idea what oil you have in the truck and always uses the same algorithm to figure its calculations. You can easily run a synthetic in your trucks 5000-7500 miles with absolutely no worries. Be sure that you are using a quality filter as well as a quality oil. -I change my oil once a year, every spring when the weather warms up.-

There are a few myths regarding synthetic oils that really seem to hang people up. One is the break-in period before you put synthetic oil in your engine. There is no reason to wait to add synthetic in todays engines. I change my vehicles over between 500 and 1000 miles for every new vehicle I get. I have never had one that used oil. The other myth is the leaking seals. You can put synthetic in any mechanically sound engine and never look back.

Again to put merit to my thoughts:
I change my oil once per year up to 15,000 using a quality filter.
I put synthetic in all my new vehicles between 500 and 1000 miles.
I have never had an oil burner or leaker in my garage.

Ken

 

i normally run regular oil for then i change it syn.after that