fiveoh
Enforcing traffic laws
i have always run 10w30 in my truck and since the rebuild i have also been using it. But lately here it has been very cold in the morning, causing the oil to be very thick at start up and i was also wondering since i am running a totally different engine (the crank only thing stock) would it hurt to run 5w30? my dad says it wouldnt hurt(he has been a mechanic for 40 years including a spec 4 in the army motorpool) but these trucks are nothte run of the mill performance cars.