Can I use synthetic in 180K 300ZX?

[MZ-Bird]

I have read yes and no from many people. I feel this site is the place when it comes to oil. Unfortunately I do not come here much so I am not able to understand all the oil jargon like some of you.
I just bought a 91 300ZX and it runs pretty good for a car with 180K on original motor.
I know it was always said never put synthetic in high mileage vehicle that always had dino oil.
Well, I assue it always had dino oil in it. It still has original Nissan shocks(which are shot) so I know the past owners didnt spoil the car.

I just bought $10 spark plugs today and do not mind paying extra for good stuff if it works better for the motor. I always used M1 in my 4.6Tbird.

anyhow. cant get a straight answer from anyone but I know you guys will have advice based on not just opinion. you guys know oil around here.


Tell me what you think I should do because I am changinf oil and plugs and brakes this weekend.

side note: cooky mechanic I bought the car from told me he always uses Valvoline Racing 50 in all his Z cars...this car was not his for long. he just bought it and had to sell it so even though he is a Z junkie, he has not maintained the car much in short time.

car calls for 10W30 from manual.

what oil, weight, dino or syn etc etc etc


thanks all

Mike

[email protected]

 

[Pablo]

I see no issue with using synthetic in a well running engine of any mileage, even one with low miles such as yours.

My Volvo has 253,000 miles. Hasn't blown up yet.

In your case I would really advise running a double AutoRx treatment no matter what oil you choose. It will release your innner Z....marketing talk for: It will clean your ring packs and make the pistons seal a lot better. Hence better running and power.

10W-30 will be fine or 15W-40 for warmer seasons.

 

[darkdan]

I recommend an auto-rx treatment or two also. Then go with your favorite brand of 10w30 synthetic.

$10 spark plugs? You got ripped off.

 

[Steve S]

why synthetic and what is the expected gain.

 

[MZ-Bird]

the recomended spark plugs for these cars cost about $10 unless I get cheap stuff that doesnt fit or perform correctly. I am not stupid. I always check multiple sources before I buy anything..i dont know why they are so much other than they are some special made plugs....

anyhow...I will see about the AUTO RX

 

[ericgl]

quote:

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Originally posted by MZ-Bird:
the recomended spark plugs for these cars cost about $10 unless I get cheap stuff that doesnt fit or perform correctly. I am not stupid. I always check multiple sources before I buy anything..i dont know why they are so much other than they are some special made plugs....

anyhow...I will see about the AUTO RX

---

I use synthetic in my 1990 NA with 190,000 plus miles. No issues.

OEM NGK plugs are the only way to go. Expensive, but they last 60K. Do you need to perform the 60K service?

 

[MZ-Bird]

I just got the car but the timing belt service was done less than 200 miles ago as well as new water pump.

just ordered a bottle of Auto RX. will treat the motor then switch to synthetic.

will change the plugs this week.

wish me luck.

 

[sprintman]

You will probably need two bottles of RX for two cleans with 180K miles on the engine IMO.

 

[MZ-Bird]

It says 2 ounces for every quart and my car holds 3 5/8 quarts of oil so I should just squeak by with a 12 ounce bottle. At least that is what I quickly read as I was placing my order.

I could be wrong.