Hi everyone, I'd like to know if it will cause any problems if I switch to 10W-40 motor oil from 10W-30. I drive a '94 GT, and it's about to roll over on 200,000 miles. It has no leaks, but it does burn a little oil at a steady rate, plus the typical blue smoke on startup. Its starting to get pretty hot around where I live, so I'm considering switching to 10W-40 for the summer in an effort to lose less oil.

Can someone tell me if this is safe to do without causing any problems, and if so, is it a good idea?

Thanks.

you're better off seeing why you're burning off oil, run a compression test and then a wet compression test to check out the piston rings.

if you come up with 'worn rings' then i'd suggest running a solvent through the oil and then changing it along with the filter. solvent like seafoam or auto-rx could help to unstick your potential stuck rings, which become stuck over time due to missed oil changes, poor quality oil, or just bad luck. \

then check the compression again, if it got better then you have/had stuck rings, some more seafoam or auto-rx will help clear that up.

if compression didnt change then you have worn rings or worn cylinders for some reason rather prematurely, tough ****. sorry to hear.