i was think of runnin 15w-40 in my car would it be bad for the oil pump does anyone run this oil

 

10w-30 is what i use

 

I use castrol 5w50
I would run mobil 1 15w50 over royal purple

 

I ran Amsoil 5w40 when i was boosted. Kept its viscosity after a day at the track.

 

look into 15-40 rotella T as well, only $10 a gal

 

where do you live and whats the temperature like in the winter ?

the W in th 5w, 10w, 15w, and 20w stands for winter. this number tells you the visocity for cold days. I live in florida an have the option of running pretty much 0w to 10w because its not cold here in the winter.
0W oil is tested at -31°F, a 5W at -22°F and a 10W is tested at -13°F

 

i live in indiana...im just lookin for oil not to break down as much after like 1000 mile my oil look like water

 

whats the coldest it gets where you live ?
whats the hottest it gets where you live ?

the best GENERAL rule of thumb is.
the best oil is the oil that is changed often.

judging oil based soley on mileage is kinda the outdated way of doing things. buy a $30 oil analysis kit and send it to an oil analysis company for inspection and they will give you a full reading of the life and wear/tear of your engine.

it’s important to have oil that is thin enough to circulate easily at cold temperatures. so that means a lower "W" # as temperature gets colder. just please dont use 0W

Heavier multiviscosity oils such as 20W-40 are for high rpm, high-load applications primarily and are not for cold weather driving.

PM me if you have questions