[quote]
Posted By Mike wheeler on 26 Nov 2007 09:41 AM
The E350 Ambulances (Ford Power Stroke powered) that I used to run in had a belt driven vacuum pump that supplied the brake booster. Things would sure get exciting at 85 or 90 mph when the pump failed, made braking extremely difficult. Would sometimes throw the belt when the pump went that was shared with the
power steering pump.
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i am now using power steering pump. and i haven't been experiencing that kind of problem yet. maybe sometimes this was caused by improper speeding up and braking of the car.