I have a 95 Pathy SE with 77k on the odometer. After bypassing and removing the old amplifiers and installing a new radio that very same day I lost overdrive. So you have a clear picture here is what happens.

Leaving from a dead stop it seems as though the car is in drive very sluggush, manuualy shift to 1st and it takes off no problem.

Seems to shift from 1st through drive but no overdrive. Switching the OD button on and off has no effect at any speed.

When coming down from highway speed I can feel the tranny trying to shift (likes its hunting for a gear). Again when leaving from a stop afterwards it feels like its in drive.

Changed the fluid which seemed dirty but not burnt, filter, and speed sensor all to no avail. Please, any siggestions?

Thanks,

Allen

Is there a difference in performance when the car is cold vs. at operating temp?

What happens when you are cruising at speed and step on the gas, does it:
downshift quickly? Slam into gear? Hunt for the gear? Something elese? The torque converter may also be on its way out.

When accelerating from a stand still, and it finally catches the gear, how is the engagement?
again- slam into gear? slip into gear (like someone learning how to drive a standard for the first time)?

Are some gear transitions better than others? IE: 1-2, 2-3, 3-4 ?

No decernable difference warm or cold, if in drive very sluggish unless I downshift to 1st.

At cruising speed and stepping on the accelerator it will not downshift, it will speed up though. When coming down from highway speeds you can feel it trying to downshift but it never does.

The engagement is fine once it is moving, say 10 or 15mph. As I said though from a dead stop it feels like staring from 3rd gear, very sluggish.

If I start moving there are no shifts as the car is in drive or so it seems, but I feel no shifts.

aholloway17 wrote: No decernable difference warm or cold, if in drive very sluggish unless I downshift to 1st.

At cruising speed and stepping on the accelerator it will not downshift, it will speed up though. When coming down from highway speeds you can feel it trying to downshift but it never does.

When slowing down, this is observed say, on an off ramp?

aholloway17 wrote:The engagement is fine once it is moving, say 10 or 15mph. As I said though from a dead stop it feels like staring from 3rd gear, very sluggish.

If I start moving there are no shifts as the car is in drive or so it seems, but I feel no shifts.

It sounds like a torque converter going bad or the clutches and bands in the transmission are burnt out.

What did you do when you changed the fluid, did you:
Change the filter?
Did you over/under refill? Both can cause these symptoms.
Remove/refill torque converter?

I'm not overly familiar with the transmission on the Pathfinders, but I'm going off whats common on other automatic transmissions when trouble shooting.

Maybe others can pop in to help-
Is there a kick down cable or switch that may be broken?

Today I drained a little fluid and replaced it with Lucas oil, after driving for 1/2 hour it seemed to make little if any change. I did change the filter when I first changed the fluid during which I did notice quite a bit of fine debris on the magnet in the pan. And, again today I could see fine debris in the fluid that was drained though I did not remove the pan to inspect the magnet.

To your question regarding the converter, when changing the fluid should the converter be dropped and filled separately? I though it would refill while filling the tranny?

I seriously doubt this contributed to the issue but...this all happened the very same day I disconnected and removed the radio amplifiers. That wouldn't have any effect on the tranny would it?
Thanks

Sounds like you have something similar to my point C in this thread:

1995-240sx-s14-auto-trans-shifting-prob ... 26199.html

OD will not engage either, no matter what you do to the button.

aholloway17 wrote:Today I drained a little fluid and replaced it with Lucas oil, after driving for 1/2 hour it seemed to make little if any change. I did change the filter when I first changed the fluid during which I did notice quite a bit of fine debris on the magnet in the pan. And, again today I could see fine debris in the fluid that was drained though I did not remove the pan to inspect the magnet.

To your question regarding the converter, when changing the fluid should the converter be dropped and filled separately? I though it would refill while filling the tranny?

I seriously doubt this contributed to the issue but...this all happened the very same day I disconnected and removed the radio amplifiers. That wouldn't have any effect on the tranny would it?
Thanks

That debris is likely clutch material or something grinding quite badly.

As for changing the fluid in the converter, I will usually remove it with the transmission and drain the old fluid and refill it before putting it back in place. Why mix new gear oil with old? Especially if there is debris in the older fluid... However, thats assuming that you've removed the transmission in the first place.

At this point you have some choices to make. You could take it to a professional shop for a transmission flush where they'll evacuate all of the old fluid via pressure and replace with fresh. BUT, some people will warn against this (rightfully so) because sometimes its that gooey/gummy/burnt fluid that is holding (dare I say welding?) the clutches and other moving parts together to keep them from letting go completely. As a result, a flush can potentially do more harm than good. (Note that this usually applies to high mileage, under maintained vehicles).

You can probably drive your car as it is until the transmission dies, but in the mean time, be on the look out for good and pick up another used example and have it R&R'd in a weekend, or you could take the possible risk of cutting the lifespan shorter than expected due to the flush. But, as mentioned, the flush is just that- a toss up chance that maybe it will fix it, maybe it won't help at all and you're out the cost of the flush (~$75-100), or maybe it'll be the nail in the coffin.
Either way, a transmission is cheaper than a new car.

Hope I've been helpful.

Also- Lucas makes a product called Lucas Slip Fix. Once upon a time we used it regularly in a Ford AOD transmission in a Mustang to keep it alive and extend its life for about 3-4 more months before it lost 3rd and 4th gear. The owner continued to drive it on 2 gears for another 2-3 months before it finally gave up.

Its not a solution, more of a bandaid.

Yes, thats exactly what I did the Lucas Slip Fix. I think it helps a bit but overdrive is gone. It does shift (after I get started in first) through 2nd and 3rd but you can feel it trying to get back to first as the vehicle slows. WOW without OD this thing drinks gas like no tomorrow. I will star teh hunt for a replacement tranny, thanks for all the comments and help.

Allen

Did you get this matter resolved in the end?

No, still limping along. There is still no overdrive, if left in drive it doesn't downshift to first when coming to a stop, also when coasting above 45mph you can feel the tranny trying to downshift. Someone asked if there was a difference in shifting when cold or hot, I've noticed manual shifting (required becasue there is no downshifting) is better when cold. I know this doesn't seem plausibe but is any of this caused by a fried OD relay?

Any thoughts?

aholloway17 wrote:No, still limping along. There is still no overdrive, if left in drive it doesn't downshift to first when coming to a stop, also when coasting above 45mph you can feel the tranny trying to downshift. Someone asked if there was a difference in shifting when cold or hot, I've noticed manual shifting (required becasue there is no downshifting) is better when cold. I know this doesn't seem plausibe but is any of this caused by a fried OD relay?

Any thoughts?

It really sounds like the same problem that I have with my 240SX as mentioned in my earlier post:

Sounds like you have something similar to my point C in this thread:

1995-240sx-s14-auto-trans-shifting-prob ... 26199.html

OD will not engage either, no matter what you do to the button.

When I disconnect the sensor, I can replicate your problem (see thread link for details) - if you can determine what that sensor is for - then perhaps you just need to replace that sensor or double check that it is correctly connected?