Best oil to use? 5w-20 or 5w-30?

[neutroncore]

Hi there,

I have read recommendations that 5w-20 oil be used in an RX-7 - mine is a 1995 model.

I got my local garage to check the Comma Oil database, and this recommends 5w-30 for the RX-7.

What do others use / recommend, is 5w-30 ok?

Thanks

Robin

[NurburgRob]

If I get the oil changed at a Mazda Garage they use the RX-8 oil which is 5-30, I also use a 5-30 mineral oil as top up

[neutroncore]

Thanks - if it\'s had 5w-20 in it already, should I drain the remaining oil and do a fill with the 5w-30, or can you top up with a different oil?

Oil is lowish anyway (and I don\'t intend to let it get anywhere near low again).

[m1tch]

Probably best to just swap oils over, regular oil changes are good

[RedRummy]

I use 10-40w mineral in mine.

[neil_jdmr]

Ive always used 10/40 halfords mineral oil in mine

[RedRummy]

yep thats the one

[NurburgRob]

Sorry, my Top Up is infact Halfrauds 10W 40 Mineral.

Topping it up won\'t kill it mate but might aswell get the lot changed and filter too

[rx7_bhp500]

dont need to change oil for the sake of it....thats for piston engines

[RedRummy]

FD oil gets prett black pretty quickly... the old wankel burns oil pretty good.

[rx7_bhp500]

FD oil gets prett black pretty quickly... the old wankel burns oil pretty good.

the oil goes black very quickly because it burns, this happens on turbo motors {temperature} -there is
nothing really wrong with the oil at this at this stage it still does its job; over time the
oil molecules sheer and effectively no longer provide the protection {think thats tech acurate}

There is a nice long tech speel on oil in this forum that describes the diff oil types etc etc...

I myself have been to reworx and the question asked is not so much "is the oil black" but WHEN LAST WAS IT CHANGED, and what has the FD been doing all this time...
Factors here are whether its mineral or syn, has it turned to sludge.....etc etc


Amen

[joshrulz]

http://www.ausrotary.com/viewtopic.php?f=16&t=263

[neutroncore]

Thanks guys

[dj_dee99]

Castrol GTX 10w40 mineral all the way for me.

[rx7_bhp500]

1. Mazda can test & approve oils till the year 2200, all they care about is the motor and its seals -when
last did you take the OEM\'s word for it,
Their motive is to make money and get you buying OEM parts and £70 per hour to change light bulbs...

2. mineral oil doesn\'t provide the protection for the turbo especially at high rpm / high performance and
thats what we do isn\'t it !? -modifying and replacing OEM....
..thats why we have synthetics and semi-synthetics....