Forum Discussion
woodhog
Jan 30, 2019Explorer
Same truck and engine, quite a few years ago I started using 5W40 synthetic in the Cummins.
If your into 15W40 in the cold its sort of like molasses in there.
Plus it takes a long time to get to the top end etc...
The starting circuit will have to work overtime to crank the engine to firing compression..
With syn 5W40 it starts like summer...
I have a friend up above you in Alberta with a fleet of dump trucks , they all are on 5W40.
If your into 15W40 in the cold its sort of like molasses in there.
Plus it takes a long time to get to the top end etc...
The starting circuit will have to work overtime to crank the engine to firing compression..
With syn 5W40 it starts like summer...
I have a friend up above you in Alberta with a fleet of dump trucks , they all are on 5W40.
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