2005 Questions for all other cars Oil pressure dropping

2005 ALL OTHER MAKES ALL OTHER MODELS
50,000 MILES • 6 CYL • 2WD • MANUAL
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EANDMPOOLS
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We have a 2005 Freightliner M2 Class. Diesel. When going 70 mph (after already warmed up), is it normal for the pressure to drop below 50 psi? It is also causing the truck (we believe) to drop speed and not be able to get back up past 65-70.
Mar 12, 2010 at 1:22 PM
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KHLOW2008
  • AUTOMOTIVE REPAIR CONTRIBUTOR
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Hi eandmpools,

The operating pressure should be at about 45 psi for most diesel engines.

I believe the diesel filter is the more likely cause of lack of power at high speeds. Clogging of the diesel filter would restrict the amount of fuel getting to the fuel pump.
Mar 15, 2010 at 12:28 PM