i did try mobile 1 before and my oil pressure was below normal but i know some others who ran it w/o a prob

 

update:
Been using castrol gtx 20w-50 for several months now and no problems. Idle oil pressure is 25 which is much higher than a 30 weight oil but it never drops below 25 psi. After a WOT pull oil pressure is still normal. As for temperature, my oil usually stays around 180F but in major traffic it jumps to about 210F and hangs around over there. Even though the temp is high it still has the same oil pressure. Like always, it seems like RRM just knows best...

 

ya i havent had probs as well.

 

If you ar not running an all out drag engine, 20W-50 is not necessary. It will cause less HP and fuel mileage and also cause elevated oil temps.

Also, you will have longer engine and especially Turbo life if you use a synthetic oil of the proper viscosity. The EVO's come with Synthetic from the factory. A true synthetic will not coke in the oil supply line as petroleum oils will thus slowly starving the turbo of critical oil supply and shortening it's life.

A 30 weight is recommended from the factory. The engine clearances are tight on these engines and will even benefit from a True PAO Synthetic in the 20 wgt range.

Thicker is not always better...


.

 

I've maintained that these claims of synthetic oils causing turbo failures was a farce a long time ago.

Hopefully with someone else whose name suggests he knows a lot about oil also saying the same, can comfort people into knowing their car will be just fine, perhaps better, using synthetic.

 

if your oil pressure is low during idle raise your idle to 1k and you should be within spec

 

You are absolutely right. True Synthetic oils will help the Turbo to live longer. Their natural resistance to high temps and cold temps, along with superior lubrication qualities are their claims to fame.

Synthetic oil is nothing new. It was developed by Standard Oil of Indiana back in the late 1920's. Hitler used it to keep his equipment mobile on the frozen battlefields and every Jet engine has used nothing but Synthetic oil since 1947.

That is where the coking problem was solved. The first Jet engines had a very short life... minutes in some cases.. Petroleum oils would not flow in the cold weather to lubricate and they would coke in the oil supply lines from literally being cooked by the extreme temps. Then they used oil tanks to keep a fresh supply of oil flowing through the engine and the used oil was burned in the engine. Still, this was not enough and a Synthetic oil was developed specifically for Jet Engines.

Then in the 60's, this little Air Force Col. (Al Amatuzio) thought, "If Synthetic oil works so well in a Jet, why can't it be formulated for a car ?" he Rest, as they say, Is History... AMSOIL was the First API Rated Synthetic Oil in 1972

 

i need to do my oil change pretty soon. 20w50 is pretty damn thick during the winter time...i really feel a power loss in 50 degrees.

 

hmm if you se really cold temps then i guess a 50 weight wouldnt be for you. But here in the islands the coldest we see is around low 70s. Noticed that my engine makes a kinda weird noise when it is cold tho. goes away after it warms up but when cold it sounds like the turbo is making a kinda fluttering sound, and the engine noise is loud... Could be from the thicker oil im thinking. Anyone using a thinner viscosity have any input on the noise on cold startup?

 

20W-50 is too thick for ANYTHING that has Stock or tight bearing clearances...

The noises you are most likely hearing is due to Oil Starvation that is slowly wearing out your engine...

You are a full 2 Viscosity grades above OEM recommended... Too high a viscosity oil will starve your engine from the necessary lubrication required, a loss of HP and Fuel Mileage and increased oil temps.

With stock or tight bearing clearances, I wouldn't hesitate to run the new AMSOIL Dominator 5W-20.. http://www.bestoil4you.com/images/RD20g2568.pdf

Doc

 

I just changed my oil today to Royal Purple 10w40... I know i know why didnt i go with Amsoil. I am not doubting anything Oil Doc is saying, i am certain he is very well educated on the topic and also thanks for helping out so much. But i live in Hawaii and I couldnt find a single place that sold Amsoil...??? Since OEM recommended oil is a 5w30 and RRM says to use a 20w50 and since Oil Doc said i could use a 5w20 i decided to try a 10w40, just a little thicker than the oem recommended. I dont feel safe using the OEM recommended viscosity since it is based on the stock 4g94 engine NON turbo. I thought a thicker oil is less succeptable to thermal breakdown versus a thinner oil? Could you explain why you recommend a 5w20 versus RRMs recommended 20w50? Please lets not start any vendor bashing or arguments, I just want to hear what everyone has to say...

 

i talked to oil doc and he said for me to use 10w40 but since your in hawaii you might wanna use something different. i need to do my oil change before it gets colder.

 

....

 

Interesting. Did he say why he recommended a 10w40?

 

im assuming because our cars made for 10w30 and rrm recommends 20w50 that 10w40 would be somewhat in the middle.