Would 10W 30 Oil Hurt the Engine

[JoshV]

I am about to change the oil my my 94 with 30K miles on it. I have always put the reccomended 5w 30 in but am thinking about using 10w 30 this time. It is a little thicker and it seems like it would give a little better protection. I don't think it would hurt but I thought I would check with anyone who has done it. If there is a reason I shouldn't switch I would like to find out before it is too late.

I would be using mobil 1 with a mobil 1 oil filter. It seems like the mobil 1 filters are as good or better than the GM filters. Thanks

[blackjack]

i was under the impression that gm did recommend 10w30 dor the zr-1...
maybe this has changed with my 93...i use 10w40 amsoil to get that bit extra protection too...i know some people use red line oil,but i have very good results in my motorcycles and my f-350 diesel with amsoil products
if you drive hard at all,go with 10w30,or 10w40....my opinion,anyway
blackjack
91/1735

[91King]

I've been using Mobil 1 10-30 fully synthetic as well as Mobil 1 filters for over three years with no problem.

[We Gone]

Originally Posted by 91King

I've been using Mobil 1 10-30 fully synthetic as well as Mobil 1 filters for over three years with no problem.

last 4 years

[40th#381]

I've been using Mobil 1 10w-30 in my 93 since the first oil change. I've used differant oil filters over the years but use Mobil -1 filters now

Jan

[RICHARD TILL]

castrol 20-50 in my 90-ZR1 and harley too for the last 7 years.

[secondchance]

My understanding of this subject is for cold start (especially in winter) low viscosity for first designation helps with faster distribution of oil. Once at operating temperture, especially in hot weather, higher viscosity for second designation would be preferable.

For this reason, 0-40W currently available for Mobil 1 would be a good choice in cold weather whereas 10-40 would be fine for hot weather use.

Most auto manufacturers typically recomend 5-30W or 10-30W and my personal assumption is, and I may be wrong, the reason they stay away from 5-40W or 15-50W has more to do w/ mpg rating than engine protection issue at high operating temperture.