Whats wrong with using the weight it was designed to use?

Can you even measure the supposed fuel gain between 30 and 40 weights?

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

You are looking at gasoline oils, you need a DIESEL oil. Which would be the 5w40 or 15w40 stuff.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Jalazia.......seriously you would get more MPG out of putting a coat of wax on the 99 and overinflating the tires than running a light wgt. unapproved oil in a Diesel engine. No one is picking on you....we just don't want to see you turn your car into a toasted sludge pot!

Cheers,

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FRED

Daily Driver: 98 E300TD 199K
Hobby Car: 69 Austin Mini
Past Diesels: 84 300SD, 312K
87 300SDL, 251K
94 Chev. K-1500 6.5Ltr.TD, 373K