Swithc to Synthetics...

NewbieZ71 · April 4, 2001

I'm a synthetic guy through and through and don't want to start the old synth vs. dino oil thread gain....decision has already been made...but when do I do it? I keep vehicles as long as possible so want everything synthetic. I know the argument about waiting for a few thou miles before switching to synth engine oil. What about everything else? And exactly WHAT else. If I want to be TOTALLY synth what would I switch and when? Have 5000 miles right now. Changed non-synth oil at 1500 and again at 3000 (because it made me feel better) and plan to go to synth at 7500 miles service. Should I have anything else switched at that point? WANT THIS TRUCK TO LAST!!!

April 5, 2001

I'm curious as well. Do I need to flush out my oil systems or just replace with synthetic?

Frank S · April 6, 2001

#Moderation Mode

Moved to the Engine forum as requested by Friz.

Moved here

April 6, 2001

Thanks Frank.

Come on, guys! Help us out with this!

Frank S · April 6, 2001

I have been using synthetics for several years now and I do believe that if you intend to keep your vehicle for a long while that they are worth the extra cost.

I would advise that you definitely run a can of engine flush along with the old oil for around 20 minutes at idle in your driveway before you drain and change to synthetics.

76BBSub · April 6, 2001

There's really no need to flush out the old fluid, since the two are totally compatible. After one or two changes all traces of the old fluid should be gone. Since it's such a low mileage truck, and you change the oil frequently already, there won't be any sludge or residue built up either. As far as changing the other fluids, I would do them at the appropriate intervals. So at 15K change the automatic transmission fluid and differential fluids. If you have a manual transmission or 4X4 transfer case change those at 15K as well. This allows everything to be broken in, but not worn, when the synthetic is introduced.

I have synthetic differential fluid and synthetic chassis grease in my Suburban.

I have synthetic gear oil in the 4-speed and synthetic chassis grease in my Corvette. Haven't changed the oil over yet since the engine has only 700 miles.

Jeff

HiG4s · April 11, 2001

If you are planning to change the oil every 3000 miles there is absolutly no reason to go to the expense of a full synthetic. The advantage of a synth is the length of use before breakdown and the better lubrication when cold at startup. You should be able to double or triple the change interval, but you need to change oil filters at the normal interval. Personally, I can't bring myself to leave oil in 10,000 miles so I use a synth blend to get the synth advantage of better lube at startup and while cold but don't have to spend as much. Also I have read where on some engines, especially older ones, oil seals don't last as long without some regular oil on them. On my other cars I use a 10w50 blend, but I know my manual warns using any oil weight other than 10w30 can cause damage. I'm not sure I understand why and I haven't checked to see if there is a 10w30 blend yet.

Eitherway there is no reason to wait if you are going to switch. After all WS6 Trans Ams, SS Z28s and Corvettes come from the factory with synthetic oil and they are virtually the same design engines.

76BBSub · April 12, 2001

I am speculating here, but there are some possible reasons why 50W could cause problems:

Boundary layer between journal bearings and crank/rods isn't sufficient to build hydraulic pressure and subsequent protection of the bearing/journal surfaces, causing premature wear and damage to bearings/crank/rods. (Most likely cause in my opinion)

Doesn't return to the sump fast enough to due heavy viscosity, so pump runs dry, damaging pump and engine.

Lifters don't pump up quickly enough, valve-lash is excessive, push rod mis-aligns and gets bent (highly doubtful)

"Splash" lubrication isn't sufficient to various parts, damaging them (not sure if SBC has any splash lubricated parts, though)

Valvetrain lubrication is insufficient....

I dunno for sure.

Jeff

TheScaryGuy · April 13, 2001

I'll stick to my 10W30 Valvoline all climate.

Pantera · October 18, 2001

Do a Mobil 1 5W-30 or 10W-30 oil and filter change as soon as you wish. Just picked up my 2500HD 6.0 a week ago and changed to 10W-30 and filter as well with only 125 miles on her. I knew that she would have debris on the factory magnetic drain plug and I was correct. The filter was somewhat loaded with the stuff too so go ahead and change as soon as you want.

If you go to a very high-end product such as Redline, Amsoil or Royal Purple then wait till about 1200-1500 miles before you change to them because of their awesome lubritious properties. Their own techs will tell you this all the time. I will switch to Redline 10W-30 when she hits 1,000 miles and use a Wix or AC Delco Ultragold filter. Also use the "Super Plug" magnetic drain plug from www.superplug.com This freak'n plug will take any metallic substance out of the oil and keep it off your filter and oil

Good luck!

Pantera

Charles · October 18, 2001

Synthetics are better when it comes to extreme heat or cold but for most people a good dino changed every 3,000 is just fine. I wouldn't bother putting any synthetic motor oil in my truck. I do use synthetics in the front and rear diffs and might put some in the trany when the time comes.

Also, in a SBC (and most other engines) splash (or I should say oil fling off the crank) is the only way the pistons and cylinders get oil. Side to side rod clearance is offten ignored when people rebuild engines and should be checked.

hudson75 · October 18, 2001

I run Amsoil 0w-30 in my 96 s-10 and have for 60000+ miles. I am a dealer and I tell people flushing does not hurt but is not necessary unless the vehicle has more than 15000 miles. Here is the reason to flush. With 0w-30 Amsoil the drain interval is 30000 miles and a filter change at 12500. Any old engine oil residue reduces the effectiveness of the synthetic because of dilution. Also higher mileage engines almost always have sludge buildup. At less that 7$ a can it is cheap insurance. All synthetics have superior properties when compared to synthetics. Also a 3-4% increase in power is common as are lower temps and better fuel economy. I and my customers have been more than satisfied with the synthetics. And yes I did experience the power increase, lower temps, and better fuel economy.