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2005 All Other Makes All Other Models Repair Question


Topics covered: Diesel, Engine, Engine performance.
Mileage: No information provided.

Asked on March 12, 2010

Questions for all other cars oil pressure dropping

Engine Performance problem
2005 Questions for all other cars 6 cyl Two Wheel Drive Manual 50000 miles

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.
Avatar Asked by eandmpools

Answer

Replied on March 15, 2010

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.

Tiny Answered by KHLow2008 (expert)
40,318 answers provided