Taurus Car Club of America : Ford Taurus Forum banner
1 - 10 of 10 Posts

· Registered
8 Posts
Discussion Starter · #1 ·
I am driving a '99 Vulcan Taurus with 71k miles. A year ago (10k ago), I noticed a somewhat unusually quick shift from the first to the second gear at low speeds. Gradually it became worse, and now it jerks and shifts really hard. It only happens when I am driving really slow in the first gear without touching the gas pedal or when I'm going down the hill from a stop. Other than this, the tranny works just fine.
The tranny is AX4S, I know it's AXOD's twin, the fluid looks fine and the fluid level is OK too.
Planning to bring the car to a tranny shop for a checkup.
Did anyone have similar problem, and what was the fix?
Any input is helpful.
Will let you know the results after I visit the tranny shop.

· Registered
187 Posts
I gave a half-bottle of Lucas transmission fix a try a few weeks ago. Now, before I get jumped on, my transmission was perfect BEFORE I added it, so I wasn't covering up any existing damage. It seems to have smoothed out the shuddering 1-2 shift that sometimes happens with any ford FWD transmission. Kinda launches into 2nd like my parents gmc safari, but not near as harsh. Anyone who has driven one of those knows what I mean.

· Registered
215 Posts
Hopefully if it's a reputable tranny shop that knows a little bit about the AX4N then they might be able to provide some help without automatically recommending a rebuild.

You also may want to find out whether your local Ford dealer has a current "reflash" available for your car's computer which can adjust the transmission shifts in order to try and remedy the problem.

And what about the fluid, you say it looks OK, but when was the last time the tranny had a full flush and fill with fresh Mercon V fluid?

· Registered
222 Posts
This exact thing was happening to my car. From a stop letting off the brake and coasting done a slight hill with foot of the excelerater it would come out of first slight hesitation then slam into second, and also some rough done shifts coming done to a stop. I had a complete trany flush, filter, and conditioner service done at the end of the summer and the transmission shifts are much improved. Were ever you take it I would stay there and watch them do it to make sure you get a complete flush. These cars are a slight pain to do because the battery and tray needs removed to access the lines that get hooked up to the machine then the battery needs hooked back up to do the service then disconnected then re installed (got keep them honest) I think Aamco offering a$100 special on the complete service. Although I don't think I would trust them to do a rebuild but flush maybe.
If you have not had the trany serviced in 71k you are over do

· Registered
170 Posts
I added Lucas tranny additive, cuz my tranny slipped really bad from 1st to 2nd, It helped quite a bit, but still, my car has 171k on it, and the Aamco people talked like it was the original tranny, it did help quite a bit cuz it doesn't slam as often and stuff, but it hasn't made it great shifting, I would reccomend it to help it, but its not gonna eliminate all ur tranny problems, so if you plan on keeping the car, I'd reccomend trying to find out what the problem is with the tranny, rather than use an additive, cuz once you get it flushed and such, the problem will be there right where you left it.

· Premium Member
5,197 Posts
Can you feel the car downshifting when you are coming to a stop? Does your car kinda feel like it is bogged down? like lack of power? If you don't add anything to help it, I'd say you got about 1500miles, thats about how much i had when i started having problems. Fluid went from pink, to dark red within a week. Good luck. If you hear a sound like ropes being pulled accross metal, its toast.

edit:haha spelled shift wrong and it got censored!
edit:ben is not too bright! censored with a C not an S!

· Premium Member
1,020 Posts
Kindof sounds like what my transmission does. If I let it idle and pick up speed to the point where it'll shift to second, it won't be smooth at all. If I barely tap the pedal, it avoids this. When the Transmission is at oeprating temps in the summer, when it downshifts from 2-1, it'll jerk like this... I've had my car 2 1/2 years, the transmission was freshley rebuilt, and it has always done this.

But if you're really concerned about it, change you fluid... even if it doesn't look like it needs it, it can't hurt to do so. I would recommend Sythetic fluids... I've been running with Synthetic ATF for almost 1 1/2 years and it has been a very positive experience. Change your tranny filter too. oh, and a transmission cooler is another good item to have... I'd prolly have blown my tranny by now if I hadn't gotten my installed. I put it on before Summer last year and other then a few quirks with the lines leaking, it's been great!

Good luck

· Premium Member
3,225 Posts

· Registered
67 Posts
It is also possible the speed sensor may be bad. It's about $25 for the part.

Here's how to replace it:

A. You'll need the following:

Two jackstands
Socket wrench
socket wrench extender bars
3/4 inch long socket
19mm long socket (95 and earlier models only)
8 mm socket
10 mm socket
13 mm socket (96 and later models only)
Lug Remover
Pliers (95 and earlier models only)
Lithium Grease (95 and earlier models only)

1. Loosen the lug nuts on the two front wheels,
jack up the car and place jackstands on each side
near the wheels. Remove the passenger front wheel.

2. Being in the area of the passenger fender well,
look into the rear engine compartment and you'll see
the rear motor mount. It looks like a fat cone.

(95 and earlier models)
Loosen but do not remove both the top and lower
motor mount bolts using the 17 mm and 3/4 inch
sockets and extender bars.

(96 and later models)
Remove the lower motor mount nut with the 3/4 inch
socket and extender bar then remove the two 13 mm
nuts on the top of the motor mount.

3. Place a jack under the oil pan and if possible,
use a block of wood between the oil pan and jack.
Jack up the engine enough so that the engine is

(95 and earlier models)
You'll see the correlation between being able to
remove the bolts on the motor mount and how far the
engine is jacked up. Alternate between the two until
the bolts and removed and remove the mount.

(96 and later models)
Jack up the engine until the mount can be removed.
Remove the mount.

4. Now lower the engine until it cannot lower any
further (it will eventually stop). Be sure the jack
is still supporting the engine.

Looking into the engine compartment from the
passenger fender well, you'll see the transmission.
Right near the top right of the transmission towards
the passenger wheel well is a cap with two 10mm or
8 mm bolts. It's really hidden unless the engine is
lowered to see it. You'll have to really stretch
your hands/arms in there to get at the cap. Remove
the two 10mm or 8 mm bolts and remove the cap. On
the cap is the sensor.

5. (95 and earlier models only)
In order to pull the cap with the sensor towards
you for easier access to the switch you'll need to
disconnect the speedomotor cable (using pliers to
remove the clip) in the engine compartment near the

(All models)
After disconnecting these, you'll gain a precious
inch or two on the electrical cable. Disconnect the
electrical connector from the switch and pull the cap
and switch out of the car. It may be possible to
pull the cap and switch out first.

6. Using the 8mm or 10 mm socket remove the clip from
the speedomotor cable going into the switch
(if equipped) and install the new sensor. Ensure the
electrical connector will fit in the sensor OK
(sometimes the sensor comes with a rubber fitting
preventing the connectors from mating properly.

(95 and earlier models)
When installing the new switch put lithium grease in
the connector where the speedomotor cable is inserted.

7. Reinstall the cap onto the transmission,
ensuring the electrical connector is securely on the
sensor. When reinstalling the speedomotor cable, it
may not cooperative about being snaked back to the
area near the firewall where it was disconnected
from. Ensure the cable is snaked back to that area
or it will be very difficult to retrieve the cable

8. Reconnect ther speedomotor cable (if equipped)
and electrical cables disconnected near the firewall
(if applicable).

9. Jack the engine back up to reinstall the motor
mount, lower the jack on the engine, mount the
tire, lower the car and tighten the lug nuts.

Good Luck!

1 - 10 of 10 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.