I’m having transmission and upholstery problems

August 1, 2010 | By Richard Prince


I have a 1991 Ford F-150 with the 4.9liter engine and the E4OD automatic transmission. Usually when it’s cold, the transmission shifts smoothly. However, when it gets warm it sometimes bangs into the 1-2 and 2-3 gears.

I know that there are different shift solenoids in the transmission but I was wondering if there was an easy fix other than having it rebuilt, which I’ve had done once already.

Also, I am looking to redo the seat covers but cannot find new upholstery kits that have the integral arm rest (I think it’s referred to as a Style 25). Any ideas?

I love the magazine even though it’s published by Bowtie News (and I’m a Ford guy).


Settle down there, my Ford-loving friend from Pittsburgh. The Bowtie in the corporate name has nothing to do with the iconic Chevrolet logo and everything to do with the publishing company owner’s choice in neckwear.

Now that we’ve cleared that up, as for your F-150, there are a few different things that could cause the hard shifting condition you’re experiencing.

A good starting point would be to check the computer for any trouble codes. Absent a trouble code that would at least tell you where to begin, likely culprits include a deteriorating line modulator valve or bad accumulators. A faulty line modulator valve will often manifest itself with intermittent hard shifts that can affect different gears. When an accumulator goes bad and causes hard shifting, the specific problem can be a bad spring piston in the accumulator.

An additional potential cause for hard shifting is wear or surface glazing of the gears. Either one can cause a little bit of slipping at the very beginning of the shift followed by a harsh engagement after the slipping stops.

I don’t have any good news with your upholstery question either. As you’ve already learned, nobody is making new integral armrests for your truck. Your options are to find good used ones or have a skilled upholstery specialist restore your existing ones.