S1lveRx8

iTrader: (1)

Slow down there, your attacking my understanding for rotary engines and oil for no reason? Plenty of people are running 5W20 with no problem.

I just pointed the finger at the oil because it was the most recent service I had done to the car. There could be plenty of reason behind my recent power loss. Coils, plugs, bad cat.

sfredrx8

Agree...Thx for your info. When did you change your diff. fluid? I have changed OEM diff. fluid & tranny fluid at 5k miles and diff. fluid was very dirty and sluggish comparing to tranny fluid at the same time. I am now running RedLine diff. and tranny fluids. Perhaps you could look into that as well.

BlueRenesis82

It's Castrol, not Castro.

nycgps

iTrader: (1)

how about the problem was there b4 u did ur oil change? its just that u didnt know about it.

most problems dont show until very late stages, just like cancer.

this wouldnt happen if u actually know how oil and rotary engine works, and its spec.

So, dont blame until you have some basic knowledge urself.

Razz1

If you change it often enough it won't make a differance.

Mercury

Shell Rotella T Synthetic 5W-40

sfredrx8

Just dig out something from nordicgroup.us webpage. "...Thicker is Better Myth
The reason that oil viscosities have gotten thinner is because bearing clearances have become smaller. Using thicker oils will interfere with oil flow and the oil pressure will increase. In a worn engine it may be okay to increase the viscosity of the oil because the bearing clearances have become larger..."

Reference only...

S1lveRx8

iTrader: (1)

Yes I will def. look into that. I can't really remember when they were last changed, which means I should do it sooner than later.

One reason exactly why I figured it didn't matter if 5W20 was used.
The car is checked/given oil between every other gas fill up, and is changed@ every 3K miles or 90 days. Either way, it has only been 400 miles or so since I changed to 5W30. Another oil change won't happen for some time.

shadycrew31

iTrader: (6)

5w-30 101,402.. bought the car 5 months ago at 96k. I do a change every month . the reason for the thinner oils is to help moving parts move more freely.

on the flip side of things if your oil is to thin you wont get lube in the right spots. which just like sex can break the condom I.E. apex seal.

my main point is don't switch your oil around to much. unlike you lucky guys my engine warranty is null and void.. So I must chose carefully what I use and I use castrol gtx 5w-30

User24

iTrader: (1)

Seem like the engine turn off faster with 5w-30 compared to 5w-20. Seems like it doesn't loose as much power in 80+ hot weather as well. None of this makes sense at all.

delhi

castrol GTX 5w20. So far so good. 8 yrs of warranty is nice safety net if anything blows (pun intended).

Brettus

iTrader: (2)

Just recently swapped from 10W30 to Fuchs 10W40

Reasons : It's coming into summer , I track the car a lot , mileage is getting up , have a small leak from front seal (still)
So i'm thinking thicker is better for me

nycgps

iTrader: (1)

that applies to Synthetic/Non-Synthetic use.

not for oil weight.

thinner oil = weaker film strength = more wear. Its scientific fact that will never change.

nycgps

iTrader: (1)

Warranty should be used only for manufacture defects.

The way u put it is, you placed a bet on "Mazda will fix your motor". and according to JD powers rating, Mazda's customer satisfaction is pretty low. so ....

Not to mention, sure lets say Mazda will cover the core, but then the dealership will ask you to replace a bunch of stuff before they will "honor the engine warranty, which might end up costing you maybe 1-2 thousand dollars of parts only

Preventive measure is always better than "hope they will fix it"

Nubo

That logic doesn't apply to 5w20 in Renesis, which is spec'ed for 5w30 oil in most markets outside of North America.

And then factor in that the Renesis experiences higher than normal fuel dilution and that it gets only partial oil changes. Both of these factors work to reduce the viscosity even further.

nycgps

iTrader: (1)

^^+1

Another thing that people seems to forgotten is that.

Why older generation engines usually can last WAY LONGER than so called "modern" engine these days ? in the old days you will not be able to find something like "5w-30" thing. most are like 15w40 or even just straight grade oil say SAE40/50.

You can improve something, but scientific fact will always stay. thinner = weaker oil film strength = higher chance of metal to metal contact.

Icemark

Yep, in the FC days the factory recommended 20W50, and 10W40 and 10W30 (for area's that didn't get warmer than 85F) on the 1986-1990 models, yet in 1991 the owners manual suddenly changed and said 5W30 or 10W30 only...yet nothing changed at all between the 1990 and 1991 model...

The only thing that changed was CARB requirements and EPA mileage requirement.

Yet, it is pretty common to see a non turbo 1986-1990 FC with 150,000 or even 200,000 miles, but much rarer too see a 1991 FC with even 100,000 on its first motor.

Rai

Kroon Oil - Presteza 5W30 (Europe)

PBlue

iTrader: (1)

The endorsement of a weekend warrior or an eastern european means nothing to me...


The guy with 165,000 miles on his car.... whats he using?

HeavyMetal699

I have used Castrol GTX 5W20, 10W30, 20W50 in the past.

Just recently switched to Redline 10W-40.

I was running 20W-50 due to the fact that when I got off work my temp would be on normal, even though I haven't driven the car all day.

nycgps

iTrader: (1)

Yep.

Oil technology did improve over the last decade. but science is based on nature and nature is based on facts. there are things that will never be able to improve no matter how advance science gets.

I just got myself some mobil1 0w-40 2 days ago. cuz winter is comingggg ! (10w40 works too, but I only have 1 gallon left so might as well just stock some 0w40 up b4 Winter comes)

I want some 5w-50, but I think only Castrol Syntec has that weight and my local Autozone (3 of them) dont have it in stock. they say they will. so I'll just wait (Yea I know how they make oils like 5w-50, but I think I will be ok as long as I drain it every 2 K miles or so plus the ultimate protect it offers OHHHH YEAAAAA ! )

StealthTL

iTrader: (1)

http://ferrarichat.com/forum/faq.php...tor_oil_basics

Dr.Haas has some good data - if you read this and see if you still think 10w30 is a better choice than a modern 5w20......

S

HeavyMetal699

Some of us are experiencing temperatures higher than normal. I can say that my car is at "normal" water temp before I'm out of the parking lot during the summer on cold morning starts. Its still on "normal" at lunch and when I get off work. Thats 4 hours of cool down. The max I drive is 15 minutes.

Either my water temp sensor is broke or the dummy gauge is set way too low in temperature or perhaps I have no reason to fear starting my car on 20W50.

At least going by the data you link.

nycgps

iTrader: (1)

I think the water temp gauge on the dash will stay at middle between 180-230f. I could be wrong tho.

You can tell the real temp by hooking it up via the obd II port, or install a water temp gauge like me

according to my water temp gauge, which was install in the upper rad hose, depends on driving condition, it can go as low as 87 and as high as 109 Celsius.

ZoomZoomH

iTrader: (1)

thank you for this link, I actually learned something new about oil and its role in engine lubrication from it.

now i need to go find Mazda's documented ideal oil flow rate for the Renesis at 7500rpm, lol

oh and guess what's his personal pick for a 5w20 semi-synthetic