When I get on it, I experience a 3 second rpm wind-up and delay before the transmission shifts (chunks) from 1st to 2nd gear. Under normal driving conditions it is fine, and the problem does not occur in the upper gears. I replaced the defective VSS but this did not solve the issue. Fluid is in good condition. Ford says it is the clutch pack @$4000 tranny change out. I will get another opinion today.

 

I'd suspect problems with either the accumulator pressure control valve, line pressure modulator valve, or the 1-2 accumulator control valve.

A transmission specialist who is very familiar with the particular transmission in your truck would be your best source of diagnostic assistance.

Steve

 

I checked with another trans repairman and he says it is a good possibility that the piston valve control spring is the culprit (common) on the E40D trans. Pressure, not tension, allows the piston to rest at various places in the sleeve, causing long shifting times. Ford now has various tensioned springs available for this application depending on the vehicle (car vs. truck, etc). If the spring is broken and has caused damage to the cylinder walls or casing, then a drill-out and sleeve-in is required. Replacing the spring is easy and inexpensive with a pan removal, but the latter requires a trans removal. Then again, you might have the answer. Thanks for the tips Steve. I will post when it is fixed.