Its time to change my cars oil for the first time. Whats the best oil to use? Should i use a Synthetic or will that leave deposist in my engine?

thanks

 

I just ordered 12 quarts of royal purple off ebay.

 

i tried to find royal purple cuz ppl say its so good but i think during the winter in ca, ppl use 10w30 and summer 20w50.. i use mobil 1 or castrol gtx synthetic

use the search option cuz ppl talked about this alot..

 

my royal purple is 10w30.

 

My royal purple is 2w-9. Sorry, i couldnt resist.....

 

Royal purple is gimik oil imo..

I use Castrol GTC 20w50 in the 159K vert
and
ELF 10w50 synthetic oil in the 80K coupe

Those are the only brands I would use in a mazda.. ELF is now recognized by Mazda to be the only recomended synthetic oil for the rotary engine (RX-8)

You have to remember most synthetic oils are not made to burn in the engine (omp) but the ELF sxr 5w30 is and that is what is recomended.. I use the 10w50 because I removed my OMP

 

why dont you research some additive packages. you might be surprised to find the additives that are good for your engine arent in conventional motor oil anymore. you would also be very surprised to find some good stuff for older engines in diesel oils, not all, but some.
also worth a note, BMW changed the oil for E46 (99+ 3 series) S54 engines (M3), they had problems with premature bearing failure, and now use castrol TWS motorsport 10w60. so the underlying message is, the additive package is worth researching in that, it contains things to prolong bearing life in harsh conditions.

 

I run castrol gtx 20w50 in the summer and 10w30 in winter.

 

What determines if it is safe or not is the ash% or something like that sort, if the ash content when burned is low it wont cause abnormal amounts of carbon deposits.

If you look on google about rotary and synthetic, you will find out this information.

From what I hear, Royal Purple, Idemitsu, Mobil1, and AmSoil are the best of the bunch.

Also, if you have removed your oil injectors, it wont matter anyway, run synthetic.

 

Valvoline 10/30 in the engine, LUCAS semi-synthetic racing 2-stroke for premix.
KLOTZ makes a very good premix but its $11.00 a qt, the exhaust smells like racing fuel though. no OMP=less weight+less headache. Used to use Castrol GTX but Valvoline seems to be of somewhat better quality.

 

I used Castrol 20W-50 in my 91 vert from the time I bought it - 1996-ish and 30,000 miles until I swapped engine a little over a year ago. The engine started and ran fine at 200,000+ miles. It was removed just to perform a turbo drivetrain swap.

I still use Castrol 20W-50 in the turbo engine except I have defeated the OMP and premix with pretty much whatever 2 stroke oil I can find with a TC3 rating.

You can't go wrong with the Castrol 20W-50. Everyone else in this thread is wrong.

 

while on the topic, i like to maintain my car in good shape, I change it every 2500, pretty insane but I care about the car lol. I'm not using syn. how many miles should we change it for our baby FC.

 

I use 20-w50 castrol GTX in my FC too, but the OP was wanting to know about synthetics so I answered, instead of telling him/her not to use synthetic and blah blah blah, like half the other people on here would do, since it's the general discretion of the board that there is only 1 way to do anything.

 

^ +1 and OEM Mazda oil filters from the stealership.

 

This is the first time I've ever seen OMP removal justified by the weight saving which is what, maybe 16-20 OUNCES?

Anyways...I run Castrol GTX 10/30 in summer and 5/30 in deepest winter now.
It gets a can of BG M.O.A. at every oil change as well.

 

OMP for weight lol.. thats rediculous.. must be drifter speak lol...

Plain and simple most conventional oil is all the same (I said MOST) if you are using conventional motor oil you will have the protection that it gives with the higher ash it gives, but will still most likley be just fine..

If you use synthetic oil just read up on what it has for additives and what specs it meets or excedes.. to say it meets and exceeds sae is NOTHING... you have to look at the engine rating a 5.0200 or a 5.0500 etc...

I will see if I can find my papers on the written letter that Mazda wrote to ELF stating what codes it needs to meet, which it does, and that they recomend it for the rotary engine.. if I can find it I will copy it and scan it and post it

Dave

 

Working OMP: Catrol GTX 10w30
Blocked OMP : Mobile 1 Synthetic.

 

I've decided to try out Spooled's Elf 10w-50 synthetic on my TII next week, cause I have my OMP blocked off.