Online Service Manual is GREAT for this sort of thing.
http://300zx-twinturbo.com/cgi-bin/manual.cgi?list=ma&dir=&config=&refresh=&direction=forward&scale=0&cycle=off&slide=11&design=default&total=33
Also, many 300ZX owners recommend using a synthetic such as Royal Purple or Mobile 1. ------------------------------------------------------------------------------------------------ I have blown motors on Royal purple. This is just water in my opinion.
The oil i usually recommend is 0w-30 from Mobile1. If money is no object get either Greddy Oil or Eneos Oil in 0W-50. On these nice engines you really want the lowest number you can get on the first number (the weight), and the highest number you can get on the second number (the viscosity). For more info or details email me at Dream300ZX@gmail.com
Yes
i have a 93 and use 5w-30. Should be the same.... i was also told that i depends on how you drive....
I use AMSoil, works awesome.
what oil viscosity should i use a gsx 1400
You should use 5W30. That is the recommended weight.
5-30 weight SM rated oil.
5W30
The manufacturer recommends that you use 10W-30 weight oil. 10 W-40 weight oil can be used in high mileage engines.
Factory said to use 5W30 weight.
If it is not burning any oil use 5w30. If it is burning any oil use 10w30.
The oil capacity of a 99 Ford Escort is 4 quarts. Use 5W-30 weight oil. Use a SM rated oil which is the highest rating.
5W30 weight.