I have a '99 Windstar with 180K miles on it. Fortunately, the tranny hasn't had any major problems until now. Once, the vehicle warms up as I'm driving at almost any speed, the tranny slips out of overdrive and the engine rpms go up. Quite often, the TRAC OFF light comes on when this happens. When this starts to happen and I am at a stop light or sign and start to go again, the vehicle shifts from first to second then to downshift gear then to second and then to 3rd, often hard if I accelerate rapidly. I've changed the fluid myself and, as we know, there is only about 4-5 qts of fluid changed like this. The problem still exists. This problem only happens after the car warms up. I've seen where some people have changed the TRS (transmission response sensor) and have had luck, but I am wondering if the car needs a complete evac, flush and fill. This really seems to be a fluid issue since the problem only happens when the vehicle is up to operating temps. One other thing I've noticed is that the only engine codes I get is the P0122 TPS a side circuit fault. Is this due to the tranny messing up or is this the actual problem. I've replaced the TPS 2x already. Other than that, everything seems to be fine.

 

First thing I must say is that this transmission is one of the worst pieces of crap that ford ever put out....AXOD, AXOD-E/AX4S These units kept us in jobs since we saw so many of them when I worked in the transmission industry...I am suprised that you have 180K original miles on the unit...since the forward clutch pistons on these units tended to crack and cause problems in forward gears.....which was fixed when they replaced the forward clutch aluminum piston with a steel one...but these are a bitch to R and R out of the vehicles. It requires complete drop of subframe and supporting of engine with engine rack...8-12 total hours of labor to pull it and replace.....one of the most difficult jobs.....yuck!

ok..since i got that off my chest...

check http://www.aa1car.com/library/transm..._ford_ax4s.htm for more info on this unit.....

I never usually say anything bad about any vehicle...But RUN AWAY from this one!!!

Bad fluid is usually a sign of a problem...not the cause of a problem. Was there particles in your pan last time you serviced it? Anything larger than grains of salt are cause for concern...signalling time to sell it!!

a couple of things cause me concern.....when you state that it is "slipping" in 4th gear...does that mean your rpms go way up and you have no forward thrust(clutch pack problem? or is it downshifting into third? Make sure you are checking fluid level when unit is hot...because low fluid level could be causing this problem....

Your transmission needs two info sources to shift accurately....the TPS (throttle position sensor) which feeds it engine speed....and output speed sensor...which tells how fast the vehicle is travelling..the transmission uses these two signals to determine when to shift.....

the description you are giving sounds like a bad TPS... Does it seem to shift at normal times with normal acceleration? if so then it isnt TPS...if it is a late and hard shift....this sounds like a bad tps.......the tranny would force a shift once OSS signal gets high enough to override TPS...the TPS code would also lead me to support this idea....but if you changed it twice.....then the sensor is unlikely to be the problem...

I would check the wiring harness that connects to the TPS...follow it back to make sure no worn spots or pinched wires....or do a continuity test to make sure there are no breaks in the wires..

if you can...hook up a scanner and test the tps signal as you run car through its paces...this would be the best way to check it...

lastly....if fluid was nasty dark or stinky.....this could mean that a clutch pack is burnt....this would tend to show up the vehicle slipping more when the transmission is hot.....which follows your description of the problem only happening when its hot...

hope this helps you narrow down your issue....

Good luck...

 

It's like it's coming out of overdrive but I still have forward thrust.

The magnet was covered with really fine metal shavings when I changed it. The oil was also normal looking (since it was all over the floor!!)

This problem doesn't happen all of the time and only when it's warm. The codes P0122 doesn't come on all of the time either. Most of the time it will drive normally and shift normally until it gets warmed up.

I will check the TPS wiring and sensor and see what I get.
Thanks

 

fine metal shavings on magnet are genreally ok as long as they are fine shavings and smaller then salt grains....if the mud (metal shavings) on the tranny pan magnet feels gritty in your fingers then that is pushing the boundary of acceptability.....

let me clarify one thing.....are you sure you are not just dropping out of TCC lockup?

when you are in O/D and speed and throttle is steady...TCC(torque converter clutch) will lockup and provide true 1 to 1 transfer of engine power to input shaft of tranny...without any loss of rpms inside the Torque converter....

when it is in TCC lockup (described above)...if you touch the throttle slightly the lockup will disengage and the rpms will rise slightly(around 150-300 rpms)...but it will still stay in O/D...and once you return to a constant speed....the TCC will engage again...returning to lockup

is this what it is doing???

 

Yeah, pretty much. But will this also affect the shift performance from a stop?

Also, on the way to work, I tried the cruise control which I very rarely use. I did this after the problem started occuring again. Usually, it will do the problem described about every 30-45 secs. With the CC engaged, it went nuts and did this a lot. On the way home this morning, I tried it again and it did the same thing. The RPMs were about 300 on the surge and it still is having difficulty shifting in the lower gears after this starts.

With the CC issue I discovered last night, I'm starting to think this might be an electrical issue or a combination. What do you think?

But, I also looked up the TCC issue you are talking about and this seems like it could be the solution. The Cruise control thing is throwing me off as well as the TPS codes.

This torque converter clutch issue, how hard is it to repair myself?

 

honestly, it could be a TPS problem that could be causing your issues.....if the TPS is registering incorrect readings as you go from low RPM to high RPM(accelerating) it could cause the tranny to shift funny....

when you described the shift pattern from a stop.....it goes from first to second....then back to first...then to second and third??? is it flaring? that is...does it feel like it starts slipping when you go into second and keep accelerating smoothly? then it clunks back into 2nd?? this would lead me to believe that you have an issue other than TPS...

Heres what I wold do.....take it to a reputable shop and have them test drive it and give you an estimate....good shops usually have accounts with your local government departements.....look for shops that work on police cars...city/county vehicles....etc

they can put a scaner on it and tell fairly quickly if a clutch pack or band is slipping...and alsi they can see if the TPS is reading normally when you press the accelerator down from 0% to 100% (and doesnt have a flat spot or spike in reading)

if you have a TPS that is reading incorrectly and spiking or flattening out its signal beacuse of problem....your tranny could act weird..\

good luck

 

it is not a tp problem. it is a tp circuit problem. you need to check wiring for the sensor to the pcm. if it is good then it will need a pcm. this will cause all of the trans problems you are having. one wire is referenve voltage 5 volts. one is a ground one is a signal return to the pcm. it should start at 1 volt and as you increase the throttle position it should gradually go to 5 volts. at wot it should be 5 volts. hope this helps. good luck

 

Then why could I be getting the 0122 code when it starts to mess up? That is a TPS A side circuit low thing? I've had some trouble with the TPS. Changed it 2x already. I will check the wiring from the TPS to the PCM. This problem generally occurs when I'm at cruising speed. The shifting issue starts after I've been there but only after everything is warmed up.

And why does it come out of traction control. The trac off light comes on when it is doing its stupidness at cruising speed.

thanks

 

thx for the information digital
I'm having clutch problems as described on http://en.wikipedia.org/wiki/Ford_AXOD_transmission.
Specifically, "Intermediate clutch failures resulting in poor 1-2 shifts or slipping are common on all AX family members." Other than the slipping between 1 and 2, my van runs great! So, even though I'm having clutch issues I'm gently driving my van out of 2nd gear then to overdrive; and obviously being very careful not to damage the transmission by revving the engine if the van is completely stopped. I don't want to change the clutch until I absolutely have to (i.e. basically until the clutch slips even more in higher gears).