Castrol magnetic 5 /30 semi or

Castrol magnetic 5/ 30 fully sim

i have uk tt man average comprestion and origanal 85k no leakes but new tubs?

10 - 40 semi is the recommended, which ive used for the last 2 oil changes, tried some 3 -30 fully synthetic this time and seems fine, a little quieter from cold i'm finding.

edit: should say 5 -30

is there any reason not yo put in full syn perfetic

Castrol magnetic 5 /30 semi or

Castrol magnetic 5/ 30 fully sim

i have uk tt man average comprestion and origanal 85k no leakes but new tubs?

 

Neither!

 

the "30" bit is too thin at high temperature for a 300zx. Go for a 5w40 (preferably fully synthetic) or 10w40. The "40" part means that the oil viscosity and stability is maintained at the high termperatures seen under the bonnet of a twin turbo.

 

Castrol do a 0w40 and most quality fuel stations will sell a good 5w40 (Shell Helix Ultra for example).

 

Richard:cool3:

0 and 5 are too thin especially as you guys are in summer. A 10W40 to a 20W50 would be a better bet

0 and 5 are too thin especially as you guys are in summer. A 10W40 to a 20W50 would be a better bet

 

Sorry buddy, that's a common misconception!

 

The first number in 0w or 5w refers to the ability of the oil to circulate round the engine from cold (ie start-up). The second number is the important one - the "40" or "50" as that refers to the stability/viscosity at full running temperature.

 

A decent synthetic oil has a lower "w" number giving a wider efficient operating range for all year round use.

 

So when hot, a 0w40 is the same as a 10w40. Oilman, our own resident pol expert and trader has posted several threads about this.....

 

Richard:chef:

Read the manual. 0 and 5 weight are not for "sustained high speed driving" as they are too thin. Your motor, your choice. I'd believe Nissan over any sales guy any day. Just my 2 cents .... errrr .... two pennies

http://300zx-twinturbo.com/s.manual/ma/011.gif

I found when i put a lower oil number in the engine goes noisy and tapperty. This goes for any car i have had.

 

I tend to stick with 20-50 it nice and thick and always makes my engine super smooth. But i do change it regular

 

I use valvoline raceing oil and it seem to do the trick :)

 

http://cgi.ebay.co.uk/VALVOLINE-RACING-VR1-20w-50-Mineral-Motor-Oil-1-x-5-ltr-/250603934386?cmd=ViewItem&pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item3a592892b2

Read the manual. 0 and 5 weight are not for "sustained high speed driving" as they are too thin. Your motor, your choice. I'd believe Nissan over any sales guy any day. Just my 2 cents .... errrr .... two pennies

 

You're still mistaken mate - the "0" and "5" weights on your own link refer to 0w20(or30) or 5w20(or 30). It's ONLY the "40" part that counts at full operating temperature and it's a (proven scientific) fact that 5w40 is exactly the same as 10w40 when the engine is running normally!

 

Richard:cool3:

I've just bought some 5w-40 fully synthetic for my standard spec JDM TT. This was after much searching on this forum and advice from Oilman. I hope this was the right choice? There are so many differing opinions on this, are they just personal preferance?

You're still mistaken mate - the "0" and "5" weights on your own link refer to 0w20(or30) or 5w20(or 30). It's ONLY the "40" part that counts at full operating temperature and it's a (proven scientific) fact that 5w40 is exactly the same as 10w40 when the engine is running normally!

I see what you are saying. I'm going to do some more research into it. An interesting topic ay.

I put in ful syinthetic and engine sounds sweet.

I just put in magnatech 10w40 semi syn last night, massively smoother and lot quieter, but i did have shitty running in oil in before...