clare at snyder.>> >>
>>> >>>>> I'm a regular guy (retired) with 4 vehicles that always have, and always
>>>>> will, get 3k oil changes on straight 30 weight oil.
>>>> This will increase the engine wear at start-up, though if you're in a
>>>> hot climate it won't be too bad. Just make sure that it's a detergent
>>>> SAE 30, not non-detergent, as both are available.
>>> There are some engines with small oil passages where it's probably not a
>>> good idea at all.
>>>
>> Not an engine built that can't run straight 30 if the temps don't drop
>> below something like 55-60F.
>
>Sure it will run, but in terms of minimizing wear, you want to avoid
>straight 30 in cold weather. Also be sure that it's a detergent 30
>weight, and not a non-detergent.
>
Can you read? 55 or 60F is not cold. 30 is good down to 55ish, 20 down to about 30F, and 10 down to about -20. Anything below -20 should either have heat or a 5W rated multigrade.
It's best to just run 10W30 if you want to maximize engine life.