So, I'm baffled here. Can anyone help?

I accidentally cracked open the transmission drain instead of the oil drain (it was a long day).... but that is fine, I needed to check the fluid anyway.

I replaced the plug, and read on here to use ATF+4, and that it is possible to fill from the reverse switch hole since it is easier to get to. So, I cracked that thing loose, and dumped in I think around 1.25 to 1.5 qts of fluid, which is a little short of what it should take if I remember correctly. The car is up on jack stands in the front, with the front tires at full excursion and just a bit off the ground (so, not too high).

So, once I overflowed out of the reverse switch hole, I plugged it back up and thought I was done.

I kept seeing red drops hanging off the bottom of the transmission case though, so it is leaking out somewhere higher up.

I have no idea why it would continually leak like that for like 4 weeks (the car has not moved and has only been run about 10 minutes in neutral).

The trans is also making some noise in neutral, but more investigation needed.

So, what is going on here? How was it holding fluid before I changed it, but now it leaks?!?

First off, please don't use ATF. It was used as a cost cutting measure. I recommend using Mobil 1 High Mileage Engine oil, 10w-30 or 5w-30 for cold climates. ATF will work but it's not the best choice. It does a fantastic job of keeping the inside of the cases clean, that's for sure.

2nd, if you filled it up enough for it to pour out the reverse light hole (same spot I fill mine), it's too full. What year is yours? The earlier ones (95-98 or so) had a slightly lower oil capacity than the newer ones as the backhalf of the gear case was changed for more oil and with more ribbing to be stronger. The earlier ones only need about a quart.

The proper way to check the fluid is to pull the rubber plug that is behind the driver's side tire. It'll be above and to the right of your axle. Let it drain out until it stops, then put the plug back in.

If it's too full, it may be coming out the vent on the top of the trans, but if that's plugged it'll force it's way out a seal. The fluid expands as you drive due to heat and needs somewhere to go.

Thanks for the information.

I read a long post a while back and it seemed the consensus was ATF+4.

I'll try to locate the plug on the back of the trans once I get the car back on level ground. I have not really given it a chance to warm up yet, so I doubt it was pushing out a seal due to pressure (yet).

The noise it is making is a bit concerning. I'll hopefully get back to it later this week. Having a baby and a project car makes for not a lot of time on the project car.

Yeah after I posted I re-read what you said. If it leaks while just sitting there, it shouldn't be that hard to find fresh red fluid. There's not many places up high that will leak on them, even if you over filled it. Wipe it down and see if it keeps leaking. You likely just over flowed it and didn't wipe it all up.

As for fluids, people can use whatever works for them, in the end it's all about the same. I prefer the Mobil 1 for price and the fact that I know it's very close to the original $16/qt stuff from Chrysler. That, and it seems that most of the transmissions I rebuild that have problems with the shift forks delaminating were ATF transmissions. But that's not a very scientific way to tell what caused it, just my observation.

For the noise, it depends on where it's coming from. Generally if it's inside the trans, you can guess what it is all you want but in the end to be 100% sure, you gotta take it apart. And if you want it fixed, it definitely has to come apart anyways. Or you can take a chance with a junkyard trans but I've blown up more than my fair share of junkyard transmissions, plus I have a few shelves full of transmissions with no diff pins in them anymore, you can tell by looking through the fresh window they opened when they left!

Hah, nice.

I'm trying to keep the budget down on this one, it is not my primary car, mostly just an excuse to play with megasquirt and a turbo (which I plan to install when I got it road worthy). Gotta ditch the factory ecu, playing games with fuel ratios and fuel cut defenders is a joke when there are good options out there for cheap.

If I do end up needing a trans, I heard the neon transmissions are stronger... should I go for one of those?

Again, thanks for your help. I'm excited to get this thing driving down the road for the fist time.

Here is a clip I shot a few days back when I first heard the noise...

It is a long boring poorly shot 'first idle' clip, but you can hear the trans noise around 2m40s:

The later Neon ones are stronger after 2001. They also came with hydraulic bellhousings as well so they'll drop right in.

Alright, enough chit chat about selling/buying/shipping. Keep this on topic and take the side conversation to Private Messages.

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2012 2500HD LML