Hi Folks,

Just bought my first diesel. 1998 E-350 PSD small shuttle bus with 125k miles. I recently drove it from Florida to Colorado and had these symptoms.

1. Speedometer doesn't move until about 40mph and then wanders right on up to 75mph and sits there until you stop. It works from time to time but very random.

2. Transmission sometimes doesn't shift out of 1st under medium acceleration but does shift when lifting off of the gas especially when cold.

3. When shifting to 3rd and 4th the entire vehicle vibrates as if the transmission isn't slipping enough to create a smooth transition. Kinda like a stick-shift shifting too soon and the car just vibrates until you have enough speed and it goes away.

4. In some rare cases, the engine rpm won't go over a certain limit in 1st until it shifts then it is okay.


I took it to the Ford dealer and they said the Tranny speed sensor and rear differential sensor were bad and that they work together.

I decided to get it home and do it myself. After replacing both of these sensors, no changes.


Facts:
E40D Transmission
Cruise Control works great
Highway cruising is good
9600 lbs



Any thoughts and os 12.5mpg reasonable for this size vehicle? It is no wider than a standard van but 2 feet higher.


Thanks!
james