10W30 vs. 10W40 The Essential Guide for Engine Oil Perfection

The Owner's manual tells us to use 10W-30 oil, what would happen if one used 10-40? will this do any harm and why? The main difference is that 10W40 oil is thicker than 10W30 oil at higher temperatures. Both have almost the same characteristics – the only difference is the ... The high detergent in Diesel oils like 15/40 had a counter-effect on the zddp additive. Essentially a higher level of zzdp was required in those oils. It's sorta like viscosity, but with a difference. People traditionally talk about 'weight' of a motor oil. The numbers 10, 30, 40 are oil ... The difference between 10w30 and 10w40 is the thickness of the oil at operating/high temperatures, at which 10w40 is thicker than 10w30. I picked up the wrong Honda oil for my 1000-5. I got 10w40 and should have 10w30 by mistake. Dealer is 45 mins away and only source of oil ... Redline's 5w30 starts out with a thinner viscosity of 10.6cst at 100c, compared to it's 10w30 which is at 11.0. Also, I've seen oil analysis ... I run 10w30 VR1 in my 200, it sits at 25+ psi at a hot idle in 90-degree Tennessee heat. If your crank bearings are in spec, 10w30 is perfectly fine. Hello. I have a mildly built 350 in a 76 Monte Carlo. I put 10w30 in instead of 10w40. Will this hurt my engine? 10W-30 and 10W-40 are very similar, folks living in very cold areas may opt for a 5W-30 and folks living in extremely hot climates may select a 20W-40/50.