353 DETRIOT OIL

[Jamie_C]

Of the multitude of older 353's i have run we always put 15-40 in them and they always ran like a top. In our neck of the woods single weight oils were virtually impossible to find on a good day.

[Maine372]

i was reading the manual that came with the TJ240 at work. it does call for 15-40. it was listed as an option alongside 30wt.  have you considered contacting a detriot engine serviceing dealer?