97 Aerostar Shifting Rough

Could anyone give me an idea of what might be causing this situation? Or how to go about troubleshooting it?
It shifts fine up and down with short trips. But if I drive it 50 mph
for 20 minutes or more, then slow to a stop, when it shifts from 2nd to 1st around 15mph, there is a sharp jolt. Then when I start moving again, it jolts around 15-20mph going into 2nd.
Trans fluid level is fine and smells normal. Looks clean and no grit when rubbing between fingers.
Thanks in advance.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Could anyone give me an idea of what might be causing this situation? Or how to go about troubleshooting it?
It shifts fine up and down with short trips. But if I drive it 50 mph for 20 minutes or more, then slow to a stop, when it shifts from 2nd to 1st around 15mph, there is a sharp jolt. Then when I start moving again, it jolts around 15-20mph going into 2nd.
Trans fluid level is fine and smells normal. Looks clean and no grit when rubbing between fingers.
Thanks in advance.
== This might help give some more info.... Last night, no problems before getting on the freeway. Drove 55-65 for 30 minutes. As I exited trans jolted about 18 mph shifting into to 1st gear. Jolted at same place as started up again. Driving 25-45 mph, repeated at each stop. Then pulled over and filled up with gas. No jolting from them on. I noticed that the engine temp was about 3/4 scale (normally about mid scale), but the temp stayed high the rest of the trip and no jolting.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 28 Feb 2014 11:05:30 -0800, "Guv Bob"

Regardless how te fluid looks, feels, and smells, I would change the fluid first. Also make sure the trans cooler is not leaking, putting coolant into the fluid. I would put either BG transmission fluid conditioner or Ford Friction Modifier additive (made for differentials) in the fresh fluis - ir sounds like you have a valve or accumulator sticking and either of these 2 routes have been known to solve the problem. The friction modifier stuff is blue - and it STINKS!!!!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Or how to go about troubleshooting it?

mph for 20 minutes or more, then slow to a stop, when it shifts from 2nd to 1st around 15mph, there is a sharp jolt. Then when I start moving again, it jolts around 15-20mph going into 2nd.

when rubbing between fingers.

before getting on the freeway. Drove 55-65 for 30 minutes. As I exited trans jolted about 18 mph shifting into to 1st gear. Jolted at same place as started up again. Driving 25-45 mph, repeated at each stop. Then pulled over and filled up with gas. No jolting from them on. I noticed that the engine temp was about 3/4 scale (normally about mid scale), but the temp stayed high the rest of the trip and no jolting.

Thanks CS. Other shade tree checks I did was to put it in drive, foot on brake and press the gas pedal. Then did the same for reverse. No slipping, noises, etc.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sat, 1 Mar 2014 08:56:18 -0800, "Guv Bob"

Is the speedometer by chance a bit irratic? Or the cruise control? Could be a flakey VSS (Vehicle Speed Sensor). That puppy is the 5 speed electronic shift trans. If the speed sensor is week the trans may not be getting a good signal at low speeds
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

situation? Or how to go about troubleshooting it?

mph for 20 minutes or more, then slow to a stop, when it shifts from 2nd to 1st around 15mph, there is a sharp jolt. Then when I start moving again, it jolts around 15-20mph going into 2nd.

grit when rubbing between fingers.

before getting on the freeway. Drove 55-65 for 30 minutes. As I exited trans jolted about 18 mph shifting into to 1st gear. Jolted at same place as started up again. Driving 25-45 mph, repeated at each stop. Then pulled over and filled up with gas. No jolting from them on. I noticed that the engine temp was about 3/4 scale (normally about mid scale), but the temp stayed high the rest of the trip and no jolting.

the

putting

or

to

foot on brake and press the gas pedal. Then did the same for reverse. No slipping, noises, etc.

Speedometer is smooth. No cruise control. Would that eliminate the VSS suspect?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

situation? Or how to go about troubleshooting it? >> >

mph for 20 minutes or more, then slow to a stop, when it shifts from 2nd to 1st around 15mph, there is a sharp jolt. Then when I start moving again, it jolts around 15-20mph going into 2nd.

grit when rubbing between fingers.

before getting on the freeway. Drove 55-65 for 30 minutes. As I exited trans jolted about 18 mph shifting into to 1st gear. Jolted at same place as started up again. Driving 25-45 mph, repeated at each stop. Then pulled over and filled up with gas. No jolting from them on. I noticed that the engine temp was about 3/4 scale (normally about mid scale), but the temp stayed high the rest of the trip and no jolting.

the

putting

or

to

foot on brake and press the gas pedal. Then did the same for reverse. No slipping, noises, etc.

- Speedometer is smooth. No cruise control. Would that eliminate the VSS suspect?
Probalby unrelated, but the last time the fluid was changed was 2-3 years ago (10-15K miles) and they over-filled it according to the dip stick. Still at same level. I remember hearing one time that if it's too full, it's not good for the trans.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload


Depending on how over-filled it is, it starts getting foamy and introduces air into the valve body and between the clutch plates. And as it warms, ATF expands anyhow, so that would make it even worse. Siphon some out next time it's warm until you get to the proper level and see if that fixes the problem. Easy enough to do to see if that's the cause :-)
--
SC Tom



Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.