when change oil and filter??

[Carguy80]

i was thinking to change my oil from mineral to synthetic blend.when would be best change oil or filter or both,to make sure that sludge wont block my filter?

and is it ok to use 10w40 oil?my owners manual says that i should only use 5-or10w30 and not to use 10w40.but where i live only oils that i can find from synthetic blends are 10w40

i have 92 firebird 3.1 112500 miles on it.

 

[dj215]

could always order online

 

[vad]

Use 5w30 mineral (dino) or 0w-30 synthetic.
If your engine is still in a good shape, the dino oil by itself shoudln't provoke any sludge forming unless you neglect your oil change schedule.

 

[Carguy80]

i dont know that if there is a sludge, i have changed my oils always after 3000miles,but i dont know what the prewious owner had done with the car i have owned the car only about 2years now and prewious owner had the car about 12years,so i dont know what kind a oil he has been using.thats why i want to change oils maybe before than usual because if there is a sludge or deposits they dont block my engine or oil filter.maybe i should change oil and filter after 1000miles and then after 5000-6000miles?i think that based on old servicetickets prewious owner was using 10w40 shell synthetic blend.but can i use 10w40 in my engine,i hope that its not too thick oil?

 

[Ugly3]

Change the oil and filter at the same time, use 5w30 motor oil and enjoy your ride.

 

[Pablo]

Do you have sludge?