93 pathy auto, won't shift, not the usual problem, I hope...

random letters · Oct 30th, 2006, 11:26 AM

Hey guys, I just picked up a 93 Pathfinder (automagic) with 200K on the clock. Engine seems OK, for the mileage and the year. But the transmission doesn't like to shift...unless I let off the gas. After that, if shifts fine. I can run the engine all the way to redline and it just won't shift, but as soon as I let off, it selects the next gear and I'm good to go. It does this in all gears, as far as I can tell.

Has anyone seen behavior like this before? I'm hoping it's just a sensor or vacuum line or something minor, since the transmission seems fine beyond this issue.

Of course, I'm planning to get a full tranny flush and do the front/rear difs, as well.

thanks
mike

BTW, what the towing capacity of my Pathy?

**88pathoffroad** · Nov 4th, 2006, 09:39 PM

No idea, these are very funky auto transmissions. There are no vaccuum lines. No external sensors to mess with that control shifting. You can try swapping out the transmission control unit and see if that fixes it, those seem to go bad sometimes.

The flush is a good idea. Trans fluid is supposed to be changed every 30k, most owners never do it *at all*. Install the biggest tranny cooler you can find and bypass the stock cooler in the bottom of the radiator, the stock cooler clogs up over time and kills the trans.

Towing capacity is 3500 lbs AFAIK.

zagan · Nov 19th, 2006, 12:01 AM

Sounds like it's slipping, you should get it checked over properly by someone who can do the job properly.

If it's the same deal as a WRX here, the seals in it are gone your simply burning out the rings in side it, once they are completely burned out you won't be going anywhere.

The WRX Auto is made to burn out straight away once the seal is broken, but if your nice at the time it'll still move the car and change but effectly you'll need to rebuild the auto, make sure you get rings that can take the extra heat once the seal is broken they'll be able to last and you simply need to replace the seal instead of the seal/ring/everything else inside the box.

zagan · Nov 19th, 2006, 12:02 AM

Also service your auto once a year/20,000klms

you'll need to work that out for miles.

tcrote5516 · Nov 19th, 2006, 11:53 AM

Quote:

Originally Posted by zagan

Sounds like it's slipping, you should get it checked over properly by someone who can do the job properly.

If it's the same deal as a WRX here, the seals in it are gone your simply burning out the rings in side it, once they are completely burned out you won't be going anywhere.

The WRX Auto is made to burn out straight away once the seal is broken, but if your nice at the time it'll still move the car and change but effectly you'll need to rebuild the auto, make sure you get rings that can take the extra heat once the seal is broken they'll be able to last and you simply need to replace the seal instead of the seal/ring/everything else inside the box.

I assume you are talking about the valve box, but with out opening up the trans, thats a shot in the dark. Start with your trans flush, pay close attn to the oil you remove, that will tell you alot about whats going on. Like 88path said, completly bypass the stock cooler (dont just add on another cooler as the stock will clog, and render your new cooler useless). If its still no good, just replace the trans, its usually not worth repairing a trans with +200k, when you can get a reman on ebay for 400 bucks. Good luck!

speedbuggy67 · Nov 24th, 2006, 11:56 AM

mine does the same exact thing. i put in som elucas trans treatment and a trans cooler as well as unplugging the gray plug on the passenger side of the engine compartment which is supposed to up the trans pressure and the pathy slips less but still doesnt shift unless i let off. I have 211k on her now guess i should find a trans in a junkyard. Def lots easier and better then working on crap o matics.

Scott

zagan · Nov 28th, 2006, 01:52 AM

Ah you can dump in another one but you could be in the exact same spot anyway.

It's better to simply re-build it as it'll go for another 200,000 or what ever you end up putting on it, the engine will probably die before the trans does if you re-build.

I have to sus out about my auto trans as well.

speedbuggy67 · Nov 28th, 2006, 11:24 AM

rebuilt autos around here run 2500 or so used trans can be had for 500 or less. If a used tranny with 60k miles lasts only 75k miles it sounds like a deal. Ive been driving mine for the lastyear with it slipping with no change in condition.

Scott