P1757 DTC Transmission does not drive in any gear

Howdy Everyone,

Well I've got some problems on my flatbed!! I went mudding and got stuck in some deep water (see pics) the engine died and wouldn't start back up. My dad pulled me out and to our local pharmacy where it sat for a day. The transmission fluid and oil were both contaminated heavily with dirty mud water.

I drained the oil water until it was in the proper range, I pumped out the transmission fluid water as much as I possibly could and it was about 1 inch above the recommended area on the dipstick in neutral.

We jumped the flatbed and it started and smoked like crazy (water in the muffler / cat etc.) after 30 minutes it was running great. Drove immediately to the nearest oil change place. Changed engine oil. Started driving home and on highway all of a sudden alot of steam came out from underneath and had no power to the wheels, engine still running great. Almost as if revving in neutral.
Got it into a parking lot and came back the next day.

Pumped out more transmission water fluid, and it drove again! Woo! drove it about 4 miles and it steamed and wouldn't drive up the hill I was on. Got pulled into a valero, then my wife came and pulled me home. It now wont drive at all even after being completely cool. I also have a code for P1757;

SYMPTOM
P-1757 GOV PRES ABOVE 3 PSI IN GEAR WITH 0 MPH

I purchased a new transmission filter, gasket, atf +4 and Governor Pressure Sensor Transducer & Solenoid 1996-1999. That is where I'm at now.

Does anyone have any ideas or pointers? (besides don't try to drive through 4 ft of water without a lift)

TLDR: Truck wont drive in any gears P1757 DTC. Contaminated Tranny fluid.

Not related to your specific problem, but every 4x4 manual that I've ever read calls for changing the differential fluid any time that the cases are sunken. Might want to consider that in addition to your tranny repair to avoid further issues.

Has the transmission been completely flushed, or did you just do a dump 'n fill? You might want to dump in fresh fluid while letting it pump out until there is nothing but fresh fluid pumping out. I would imagine that even a small amount of water mixed with tranny fluid will cause issues. It's supposed to be a sealed system after all, LOL.

You could pull a cooler line and let the truck run in neutral while you have a funnel and a bottle of fluid going through the top. Don't do this long though if you do try. You gotta get that water out.

Honestly you're probably ****** in the long run though

I have not done a transmission flush, I should have at the shop I received the oil change from.

I will pull the the top cooler line and funnel some fresh atf 4 in, Do you recommend leaving the pan off for this?

Also I didn't know about the transfer case needing to be emptied and refilled, how do you even get more fluid in?

Why do you say I may be screwed in the long run?

The system pushes fluid not pulls so don't pull the cooler line going TO the trans. The one going AWAY is the one you need. Pan definitely on and full or you'll burn that ***** up quicker than ****. Honestly don't even know that i would do all of this but if you still have water in there it's a problem.

The reason i say screwed in the long run is because water in trans is fluid is like water in engine oil. No Bueno. Doesn't lubricate and causes damage to the internals

Honestly my first suggestion is probably a messy and horrible idea. Prob better off doing multiple fluid changes like you would normally with a little driving in between. 2-3 changes total should be plenty good i would think

I can do multiple changes with the new filters, but the problem is it doesn't move in any gear forward or reverse 2wd or 4wd. I'm hoping changed the governor and solenoid will help in some way.

DodgeTx said:

Also I didn't know about the transfer case needing to be emptied and refilled, how do you even get more fluid in?

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I used one of those funnels with the bendy fill tube. There are two plugs, the lower one is obviously the drain, the top one is the filler. You'll need a big allen wrench and if the case has accumulated years of dirt and mud, you might have to dig for them.

The differentials aren't as easy. For whatever reason, Dodge decided to not to put drains on them, so you have remove the entire cover, which is held on by what seems like thirty bolts. May as well drop a couple extra bucks and replace the gaskets while you're in there.

Not sure I'd get too frazzled about the tranny yet. We had an old Malibu that got a big hole punched into the pan (old shocks + big rocks). The thing ran itself dead empty and we just barely got it moved back to the house. New pan, new fluid and a few years go by and last I heard, my niece is still driving it.

But you're definitely going to have to get every drop of water out. Probably gonna take several flushes. I hope you've got some cash to burn, cause that ATF+4 gets pricey quick.

Actually the trans is what I'd worry about. I wouldn't worry much about the diffs or t case unless your vent lines got submerged. The units are completely sealed except for the vent lines but those SHOULD be high enough to not be a problem. T case line is back by distributor so it should be fine but the front diff is on the passenger inner fender and i would definitely check the rear

I wouldn't concern myself with t case for the moment. Totally sealed except for the vent line and it uses a check valve up next to the dizzy. Should be plenty fine. Differentials same thing but the lines are shorter so check out how much crud is on the lines before worrying about your diffs.

If there was water circulated through your transmission at all, you're screwed. The clutch packs and friction material on the bands, uses a glue that is water soluble. If you pushed water through there, that glue has moistened back up and moved elsewhere. It may run for a bit after a fluid flush or change, but don't ever expect to tow anything, or drive more than a few thousand miles reliably with it ever again. At least until you rebuild it.

As for lubrication, nothing is damaged internally as far as wear is concerned, but water causes rust. Good news is, everything is covered in oil and oil is a water repellant. As long as you fully flush that thing as soon as possible, you should have minimal rust issues, keyword "should".

For flushing it, nothing short of a complete flush is good enough. One way to ensure a complete flush on automatic transmissions without an expensive machine that hooks up to the cooler lines (none of that down the dipstick hole ********) is to place the return line in a bucket of new fluid and the 'hot' line into an empty bucket. Make sure you either have someone watching the bucket of new oil to make sure you don't suck air for very long, or you can see it yourself. Then run through every gear at idle until you have sucked down about 1.2-1.5 times the system capacity. (you can use junk oil from someone else's transmission change so long as its not contaminated with water, this can save you a bit of money, and it wont damage anything as used oil is better than watery oil)

Really, you are only looking at new bands and clutches, perhaps new sensors depending on if they are water damaged. Everything else will be fine so long as there isn't a bunch of rust. You won't even have to pull apart the valve body.

Just change the fluid at 5K miles after the rebuild (unless you get it professionally remanned by someone who you are sure will remove all traces of water).

Tcase will be fine, Diffs will be fine, just change the oil to be on the safe side. As oil for two diffs is an order of magnitude less than a new diff because it got water in it and blew up.

Engine is iffy, in theory it should be sealed, but in reality its not. I'd change the oil at 2-4K intervals for the first few changes.

We rebuilt the engine and transmission in a fire truck that had been caught in a flood, back when I was still a diesel tech.

So I drained the transmission completely of the water / tranny fluid this morning and then put pan back on with 3 bolts, came back after church and drained out some more that had collected in the pan cleaned out the pan dry with a towel, put it back together with 8 bolts (2 on each side) and filled up with 6 qts of atf 4 let it run through all gears for 3 minutes each. Will drain and refill along with filter change tomorrow after work. The fluid now looks as it should, but still better safe than sorry. Reverse is working again, however no forward gears.

I have not yet changed filter, or the sensors (I'm waiting for them to come in the mail)

DodgeTx said:

So I drained the transmission completely of the water / tranny fluid this morning and then put pan back on with 3 bolts, came back after church and drained out some more that had collected in the pan cleaned out the pan dry with a towel, put it back together with 8 bolts (2 on each side) and filled up with 6 qts of atf 4 let it run through all gears for 3 minutes each. Will drain and refill along with filter change tomorrow after work. The fluid now looks as it should, but still better safe than sorry. Reverse is working again, however no forward gears.

I have not yet changed filter, or the sensors (I'm waiting for them to come in the mail)

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There are a bunch of things that can cause no drive ranges, however most of the time, its the rear clutch, overrunning clutch, or valve body malfunction (full of water).

The problem with water if it has spent any amount of time in the internals, is surface tension. If the protective layer of oil has worn away, water will stick to small cracks and crevices . The valve body is nothing but small passages and tights spaces. Since water and oil don't mix, its possible that there is water stuck in the valve body still and causing problems. Another very likely possibility is the clutch packs have been irreversibly damaged by water.

One thing I forgot to mention in my last post is sealing the transmission dipstick and vent tube. You must seal the dipstick with a cork covered in oil, or by sticking a rubber stopper covered in oil in it. The vent tube can be clamped shut. Otherwise a vacuum will not build in the transmission and it will have a hard time pulling oil into the cooler return line and you will just empty the pan. Pulling a vacuum is required as it draws fluid into the transmission much better than it is able to at atmospheric pressure.

I think you got a good start. Do the last change and do the sensors and **** at the same time and see where you're sitting

will update once sensors come in. Can one of yall take a pic of the line coming from the tranny and line going to? I need one of those fuel line removal tools to unhook them right?
Also do either of y'all have any insight on how to remove the valve body?

I spoke with a manager at autozone, and he said more than likely my torque converter has the most in it and is probably my main issue. what do y'all think?

Valvebody is dropped by removing 10 T25 screws from valvebody. However to do those electrical pieces you don't have to drop it.
Watch this for help on that.
https://m.youtube.com/watch?v=kvl-_-vY6rk

I don't believe tq converter is the main issue though it probably got water in it as well yes. Your current process should take care of it fine. Considering the codes you have for line pressure can certainly keep the vehicle from moving id start with that. Later on you can always pull the inspection cover and drain/refill tq converter

I actually did already watch that video. I do have some good news, I drove around my neighborhood in reverse today to help circulate the new fluid, I then checked it fairly contaminated again. I drained the fluid again and changed the filter too also removed what I thought was the valve body (haha I was wrong) it was the piece those two connectors go in and cleaned everything well again. I put it back together and refilled with 6 qts of atf 4 I put it in reverse and it still worked so I figured heh why not drive! I tried drive and it drove. I had to push a little more on the gas than usual but it went! drove around neighborhood twice, then reversed around a bit. Drained again removed same part with sensors cleaned pan, and chnaged filter again. refilled with atf 4 6 qts and drove around some more.

Its driving again! Not great but moving on its own. Plan to get the tranny flushed tomorrow at jiffy lube or ntb, cruise 100 miles or less then change filter once again.

Took the flatbed to jiffylube and they flushed it 4 times. its shifting fairly well now. I do have another problem though, now the trans temp light is coming on. I believe it to be due to a clogged check valve and am doing a check valve delete today to see if that fixes my issues. If anyone has any other ideas please let me know.

Best advice is to stop trying to use your truck as a boat.

Well just took her for a test drive about 15 minutes and upon returning to the neighborhood it started slipping on takeoff and once getting up to speed wouldn't shift up to 2nd. Gunna drop the pan again tonight, change the filter those two sensors I bought and drop the valve body as well.