32RH foamy transmission fluid

Cowbird

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Hi all, I'm on the tail end of finishing my frame up rebuild of my 2000 TJ for my daughter and we are starting to drive it around a little. It's a 4.0 with a 32rh that I rebuilt myself thanks to the great help here in the forums and especially with @hear youtube videos. I also relocated the vent to the top of the transmission and added a deep pan and temp sensor while I had it out. After short drives around town for about a week I decided to drive it to my brothers house that's 2 hours away on Thursday, everything went great, trans temp was 160-180 the whole way there and when I got there I checked the fluid and it was on the mark, the next night when I drove back was the same except the engine coolant temp was slightly higher than the trip there (just to the right of 210, maybe 225?) but only when going uphill for a stretch mostly, other than that the needle stayedat 210. The following morning my daughter noticed a little transmiision fluid on the ground and after investigating I found it had came out of the vent tube that I had ran up next to the dipstick. I thought maybe it had a belly in the tube and some had been trapped and had gotten pushed out, so I had her take it on a drive around town and when she got back I checked the trans fluid and it was still good and the fluid itself looked like brand new. Today she took it out and drove around a while and when she got home I went and looked and there was a little bit of foamy pink fluid on the end of the vent tube but when I pulled the dipstick the wasn't any there, just pink transmission fluid. It's got me scratching my head on this and I'm thinking maybe air in the system? Any ideas are welcome and appreciated as always!
 
Hi all, I'm on the tail end of finishing my frame up rebuild of my 2000 TJ for my daughter and we are starting to drive it around a little. It's a 4.0 with a 32rh that I rebuilt myself thanks to the great help here in the forums and especially with @hear youtube videos. I also relocated the vent to the top of the transmission and added a deep pan and temp sensor while I had it out. After short drives around town for about a week I decided to drive it to my brothers house that's 2 hours away on Thursday, everything went great, trans temp was 160-180 the whole way there and when I got there I checked the fluid and it was on the mark, the next night when I drove back was the same except the engine coolant temp was slightly higher than the trip there (just to the right of 210, maybe 225?) but only when going uphill for a stretch mostly, other than that the needle stayedat 210. The following morning my daughter noticed a little transmiision fluid on the ground and after investigating I found it had came out of the vent tube that I had ran up next to the dipstick. I thought maybe it had a belly in the tube and some had been trapped and had gotten pushed out, so I had her take it on a drive around town and when she got back I checked the trans fluid and it was still good and the fluid itself looked like brand new. Today she took it out and drove around a while and when she got home I went and looked and there was a little bit of foamy pink fluid on the end of the vent tube but when I pulled the dipstick the wasn't any there, just pink transmission fluid. It's got me scratching my head on this and I'm thinking maybe air in the system? Any ideas are welcome and appreciated as always!

Bad radiator most likely
 
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Mine ran close to 220 right after the rebuild, but it was definitely correlated to ambient temps. It would be ~180 on the way to a friends, but that was with the TX sun at my back, and then pushing 220 on the way home, dead into the sun on 100+ day temps.

Then I put a cooler in, and it has never been over 170. I purposely put the temp gauge in prior to adding the cooler to know what benefit the cooler was.
 
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Bad radiator most likely

I thought about that but the transmission fluid isn’t milky like it’s been contaminated with water. I’ll have my daughter drive it around for a bit before I get home from work and see if it’s foamy at the vent tube again so I can try to get some pictures to post.
 
Mine ran close to 220 right after the rebuild, but it was definitely correlated to ambient temps. It would be ~180 on the way to a friends, but that was with the TX sun at my back, and then pushing 220 on the way home, dead into the sun on 100+ day temps.

Then I put a cooler in, and it has never been over 170. I purposely put the temp gauge in prior to adding the cooler to know what benefit the cooler was.

That’s part of what has me thrown off is that the trans temp stayed between 160-180 on the 2 hour trip there and on the way back and the engine temp never got over around 225, so I don’t think this is a heat issue. I’ll try to reproduce the situation and get pictures of some stuff.
 
Oh you said engine temp, my bad. I haven't had foamy ATF before, so I have no thoughts there. Sounds like you've read my theory on the transmission puking after the vent relocate.

I am a little concerned with your use of "pink" as a descriptor. I mean, clean atf has a hint of pink to it, but usually if pink is the word used it means there is water in there. Is it possible you got water in the breather tube and there is still a low spot in the hose?
 
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Let's brute force this. Get the transmission up to temperature, and then take the pressure/hot side cooler line and disconnect from the radiator and stick it into a bucket. Careful, it's gonna be like 200F. Put the jeep in N and fire it back up. Let's see what comes out. If it ain't PURE atf, then we have a problem.

Video it & post.
 
I am a little concerned with your use of "pink" as a descriptor.
Poor description of the fluid color on my part, probably because the Jeep is pink 🤦🏻‍♂️
Let's brute force this. Get the transmission up to temperature, and then take the pressure/hot side cooler line and disconnect from the radiator and stick it into a bucket. Careful, it's gonna be like 200F. Put the jeep in N and fire it back up. Let's see what comes out. If it ain't PURE atf, then we have a problem.

Video it & post.
I ordered a new radiator from Napa today that is supposed to be OE specs, it wasn’t the cheapest one they had or anything, the one that is currently in the Jeep definitely isn’t mopar. The new one is supposed to be here Wednesday, so I’ll try this out tomorrow night as I won’t be home from work until late tonight.
 
Did you do something to the pickup to match the deeper oil pan? Is it possible the pickup is sucking air?
The new deep pan came with new filter and extensions. I’m tempted to take the console and shifter out and try to look from the top and see if the relocated vent might be part of the issue, the fitting I got is this 90 that swivels, which seemed like a good idea when I was putting it in so it could move to whatever position the tube was ran but now I’m curious if it could be pulling air around it
 
The new deep pan came with new filter and extensions. I’m tempted to take the console and shifter out and try to look from the top and see if the relocated vent might be part of the issue, the fitting I got is this 90 that swivels, which seemed like a good idea when I was putting it in so it could move to whatever position the tube was ran but now I’m curious if it could be pulling air around it

I guess that's possible, did you use an NPT tap? The fittings are npt, i think. But IDK, all I know is that I have a special tap for that task.
 
I guess that's possible, did you use an NPT tap? The fittings are npt, i think. But IDK, all I know is that I have a special tap for that task.

Yep, I used the correct tap and made sure it was snug and not over tightened and used a little Teflon tape (didn’t want to use any type of pipe dope because I wasn’t sure how it would affect the atf+4) - the attached image is the type of fitting I used, if you look above the threaded half you’ll see the line where the two pieces meet and it swivels, it might be perfectly fine but now I’m skeptical of it. I’ll probably have a looksie while I’m doing everything else just to see if there’s any indication of a leak.

IMG_2736.jpeg
 
I have the same thing only no swivel. I would doubt that’s the problem honestly.

If you have a drain plug in the pan, just drain the fluid into a clean bucket. If it’s good, just put it right back into the transmission. That’s way easier than my brute force suggestion from earlier.
 
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I do have a drain plug on the pan, I’ll crack it open tomorrow after work and take some pictures of what I find.
 
Here are a few pictures of my transmission fluid. I had a spotless 5 gallon bucket I used to catch the fluid in and I took a cup full and put it in a ziplock bag to be able to see it better.

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Would love to have another opinion here but it seems "milky" to me. It normally has a transparent quality to it, but that looks more like you shoulda had a V8.

Ooh... I have an idea brb.
 
I thought it looks thick (best way I could describe it) but figured it would be a lighter color if mixed with water. I've got my bucket with the trans fluid covered to keep anything from getting in it, I'm going to let it sit a while and check and see if there's any separation. I'm looking forward to your idea in the mean time :)
 
This is brand new fluid out of a spare quart I had. It’s way more translucent and a more vibrant red. I think yours is contaminated tbh.

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I agree. Welp, I should be changing the radiator tomorrow evening so there's that. I'm going to leave the drain plug out overnight and disconnect the lines at the radiator to try to get as much out as I can with gravity, hopefully there won't be much left in it except the TC
 
I agree. Welp, I should be changing the radiator tomorrow evening so there's that. I'm going to leave the drain plug out overnight and disconnect the lines at the radiator to try to get as much out as I can with gravity, hopefully there won't be much left in it except the TC

That's cute.

You would not believe how much comes out when you disconnect the lines at the transmission, even after draining the pan, the radiator, and what you can get out of the lines. Last rebuild I did we turned it on it's side and I swear 4 more quarts came out of the cooler holes.

Here's the real issue. If you really did get water in there, water breaks down the glue on the frictions and the kickdown band. IDK about the L/R band, it's made of something entirely different. But it wouldn't suprise me if you had some trouble down the road. Yours isn't super contaminated, so you may not be in the actual danger zone, hard to say. I wonder, did you maybe have water in it after you cleaned the case?
 
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