Transmission not shifting out of first gear

Sounds great and thanks for viewing the other post.

However, we need to jump straight to where they left off and check the line pressure in each gear.

Also, if you had to add fluid, the most likely cause of this is we have internal transmission damage at this point, but we need more evidence before we get there.

It is always a good idea to service the unit when having issues so here is a guide that will help with this, but I would suggest taking line pressure readings first. This is going to tell us what is going on inside the unit when trying to shift.

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

More than likely you can get this pressure gauge at a tool rental parts store but if not, they are not too expensive. Just Google Line Pressure tool for 4F50N or AX4N transmission.

Let me know what questions you have, and we can go from there, but we need this info to know possible issues. Also, can you shift down to the manual gears and see if they operate?

thanks KASEKENNY for picking up on this and thanks for helping me go through this step by step. I have the car on lifts now and I ran the test at both ports and the pressures were recorded at WOT. My pressure gauge only goes up to 100PSI. I think the pressures are pretty good?
The transmission sensor moves freely on top of the transmission when I shift gears and I could tell no difference when I drove the car in both Ds and in 1.

Okay. We need to back track a little and we may have to run these again if your gauge does not go above 100 PSI.

First you need to start with checking pressure in the line pressure port (port 2 in the picture above). If they are not correct, then you move onto port 1.

Then we need to do this test at idle and then at WOT. However, take a look at the chart below. I am not sure why they broke it up like this, but the top red box are proper pressures at idle.

Then the lower red box are pressures at WOT. We only run the WOT test when in gear.

So, if all these pressures above were taken at WOT then all of them are low.

If you look at the chart again below, you are looking for pressures in the column labeled Line, when you are in pressure port 2.

Then the EPC is port 1.

So, you ran the WOT throttle test in both ports which would be the lower red box on the chart below and all of the PSI in port 1 should be 70-90 and then over 200 PSI for port 2. Your readings were low in both ports if these were taken at WOT.

Let me know if that makes sense. Thanks

Oh. I understand the table now. I recorded those pressures with the car on lifts and no wheels on the ground and then I pressed the accelerator to the floor at each gear setting. From your reply I am guessing I did that wrong.

Okay. Yes. We want to do it on the ground, and it is called power braking it. Basically, this is a stall test as well, but we need to see the pressure with a load on the unit.

However, we don't want to do that for long as prolonged power braking will damage the torque converter.

Let us know how it turns out. Thanks

Okay. I had to order a pressure testing unit that goes to higher PSI. It will arrive on 10/30 and I will do the tests shortly thereafter. Thank you!

Perfect. We will be here when you get back. Thanks for the update.

Bad news: I got the pressure gauge (0-500psi) in the mail yesterday and I just completed the readings (attached). This gauge seems to read 10-20 psi lower than the first gauge I used (1-100psi). I guess that means the transmission is shot.

Yes. Unfortunately, that is exactly correct. What this means is since they are all low and not just one gear is that you have a leak in the pump chambers or possibly torque converter that when you build pressure, it is not able to hold the seal and it bleeds off pressure.

If you notice that the idle PSI is fine which shows that the pump is working but once that pressure increases, it opens up the seal that is cut or weak and bleeds off the pressure.

This means we need to at least go into the unit and rebuild it but if it were me on this vehicle, I would just replace it as it will be about the same cost unless you are going to rebuild it yourself and save on labor. They have rebuild kits that are pretty cheap and they are not that hard to do. However, there is a lot to be said about getting unit that comes with a warranty for less the $2,000.00.

Let us know what you decide, and we will be happy to assist with any other info. Thanks for updating us with what you have found.

Thanks this sad but true diagnosis. I would like to see if this is something I can tackle with a rebuild kit. Can you recommend a video I can watch to see if this is something I can do myself?

There are a lot of videos out there, but I would just do a Google search for this phrase and there is a pretty good video that is a slide show showing each step.

AX4S Assemble Process

We don't link outside videos just because if they are ever taken down then we have a link on our site that does not work. This is a slightly different unit then your vehicle, but the steps are all basically the same.

However, I am including the entire process from the manual attached below. This is a lot of information, and the hardest thing is measuring for the selectable bearings. If you are comfortable using a dial indicator, then this is not a big deal. Most all the special tools required are available at parts stores that have tool rental programs.

Let us know what you decide. Thanks

Thanks for this detail transmission information.
I have been watching videos related to the removal and rebuild of this transmission. I currently have three Hondas and I do all the servicing and repairs on these including brake work and timing belt changes. I am leaning towards the thought that it might be a bit too much for me to rebuild on my own. It seems there are so many steps, and I am not sure I have the confident to do this alone. It looks like I will need to invest in some equipment (i.e. engine support bar). The last time I tried borrowing a tool from a local parts store it proved be frustrating because they did not even have an oxygen sensor removal tool to borrow. I take care to maintain all my transmissions and I have never had one go out on me (35+ years) and I feel that if I invest in transmission tools, I will never use them again.
I will call some transmission places in town next week including the Ford dealership to get an idea on costs and warrantees.

I wonder if you could answer some questions for me:
This car was given to us by an older lady that moved out of town. I have tried to make contact with her to see if any transmission servicing was done but I cannot reach her. The car ran fine when we got it and I did some initial inspection of the engine. The oil level was fine, and I checked the ATF dipstick, and it was way up the line. My thought at that moment the level was probably going to be good at idle because it was high on the dipstick with the car turned off and there was no ATF leaking. I proceeded to change the spark plugs, coil, and wires because a misfire was showing. These changes fixed the misfire. I started checking the ATF dipstick when transmission problems were starting. On two separate occasions I had to add ATF at idle. Quite a bit on the second time. Could there be internal leaks going on? I see no evidence of any external leaks.

There is a lot of talk on the internet about people getting incorrectly repaired transmission swaps. Also, I am concerned that these transmissions are not reliable in the first place. Is this a concern I should have?

This car has very low miles (49,000) and I really like the raw power this car delivers and my decision on whether to junk it makes it that much harder. Thanks for your help!

I have seen this a couple times when someone gets a vehicle. What I suspect has happened is there was a leak that caused the fluid to be low and this started the issues. The previous owner had them fixed but they didn't properly fill the unit. So over time the unit fails due to being low on fluid.

Clearly it was not driven very much so more than likely the gaskets dried out and it leaked. Then if it was not filled properly and still not driven very much then any issues would not have been discovered as a vehicle can drive low on fluid.

Transmission fluid does not burn or evaporate so even if there were internal leaks the fluid would just go back to the pan.

The only time that the fluid can drop when there are no external leaks is on 4WD trucks and the transfer case seal leaks and it fills the transfer case. Clearly that is not the issue here.

Let me know if you have other questions or how this turns out. Thanks

I want to report my progress thus far. This weekend I removed the CV axles and the items (wire connections and air filter housing) that are above the transmission in the engine bay. Also, I drained the ATF and noticed a large amount of fine metal on the magnet. I bought an engine support bar and my next step is to install this and then remove the subframe.

Yep. That amount of metal is a clear sign that it was just worn out. More than likely that metal is getting into the valve body and causing solenoids/valves to stick or even the clutches to not engage.

You can try cleaning that magnet and pan out and then you will need to flush the unit and not just refill it. In fact, I would reverse flush the cooler and I am attaching that process. Any metal in the unit will get caught in the cooler and then will be released into the unit over time.

So, if you end up replacing the unit as well, you need replace the cooler or the metal will be released into your new unit.

I would do a Google search and look for a flush machine and most parts stores have them as rentals. You can try this yourself and just route the return line to a bucket and the supply line submerged in a bucket of clean fluid. Basically, you are using the pump to pull in new fluid. However, this is not the easiest thing to do so finding a machine that has a reservoir is much easier.

Seeing this transmission needs to be pulled apart for repair, would it be easier for me to buy a new radiator instead of trying to flush the lines out?
Or do you believe this metal stuck in the system is the cause of the low-pressure readings?

If you are rebuilding it or replacing it, I would not try and flush the cooler as it is too much of a risk. The only time you flush it is when you are just flushing the unit to replace the fluid. Any major repair, it is far better to spend the money.

If you don't, I have seen many times, where the new/rebuilt transmission becomes the filter and eventually you will get all the metal out, but it may take two- or three-unit replacements to do it. I have seen dealers do this.

Just a confirmation, I should spend the money on a new radiator if I am going to rebuild or replace the transmission? Is the cooler and radiator one in the same?

That is correct. I am attaching the info on this including how to replace it.

Any time you are going to the trouble of rebuilding or replacing the transmission, I would replace the cooler along with it. It is not worth the risk in having any metal left in the cooler that will be released into the fresh unit.

Okay, everything is disconnected or removed for the next step: removing and lowering the transmission. While I was under the car taking pride in my work, it dawned on me that taking a lot of stuff out makes replacing radiator hoses that much easier. I can see the two large radiator hoses and I think there are three smaller diameter hoses? It looks like there are also two hoses for the heater core. Would you happen to have a listing of all the hoses that would carry the coolant so I can order them and replace them all?
Also, I should change out the oil pan gasket (small leak around this area) and the seal that is between the transmission and engine. Am I missing anything else? Thanks!

I called my local Ford dealership to get a price on a Ford factory rebuild transmission and they quoted me $2,911.00. I called them in case I take the transmission apart and if I feel I cannot repair it correctly. They also quoted me $1,200.00 for labor but I can do the swap now.

The only two hoses that I show being molded lines are the upper and lower radiator hoses.

That means the other hoses are most likely just bulk hoses that you can get at any parts store, and you cut it to the length that you need.

This may not be correct, and Ford actually has a listing for them, but All Data does not list anything, and I cannot find them on RockAuto either. However, keep in mind that even if Ford has a molded line, it is not necessary to pay significantly more when bulk like will work. So, if it is not routed near something that could rub the hose then I would not spend the money on that and just replace it with bulk line.

There is a small line that comes with the upper hose so if this is one you are seeing then that will be provided as shown below.

That price is not bad for a replacement unit. Sounds like a good plan. Thanks

I am attempting to remove the transmission from the engine, and it won't come all the way out. Do I have to unbolt those nuts that hold that gear to the torque converter? If so I do I rotate this?

sorry, that was it. I removed those nuts and the transmission is now out.

Sorry for the delay. Yes. Those are the torque converter nuts that hold the flex plate (which is connected to the crank shaft) to the torque converter.

Glad you figured it out. Thanks for updating us.

I have the transmission essentially apart except I have not taken apart the gears unit that houses the clutch plates. I have attached an obvious problem I discovered; however I could not yet see any other problems. Are there specific parts that I should take a picture of and send for your inspection? Thanks!

Oh my. Yeah, that is an issue. I can't tell but is that a band accumulator (the piston that applies one of the drum bands)?

There isn't anything specific that I need to see but I would replace all the steel and friction plates. There should just be a large snap ring and they will all come out. You will see a piston on the bottom of the sets, and you want to check and make sure the seals are not cut.

Then soak your friction clutches for a few hours in transmission fluid.

Okay, thanks. I removed all the clutch plates. The area where that the seal was damaged was the reverse shift accumulator (circled in red in picture). Do you believe this was the only cause of the transmission failure?
I would like to replace all the seals at potential leak areas while I have everything apart. I am having a hard time finding part numbers on the web. Do you know of a place I should look?

It is hard to say when rebuilding these units if something is the only cause.

Basically, we have to rely on what we find and what the vehicle was doing. So based on the fact that you had little or incorrect pressure and then vehicle would not shift properly, I would say this would explain it.

If this was not sealed then you are going to lose pressure and if you have low pressure, it is not going to shift properly or at all.

However, what you are doing is all we can do when we are rebuilding these. Inspect everything and replace what you think is questionable along with all seals and clutches. Coat all seals in transmission oil or petroleum jelly so that they don't go together dry. This is how to prevent ripping them on installation or first start up.

Lastly, when you get it all back together, if you can do an air check, which will help but you want to lift the drive wheel, fill the unit and check the pressure again before you go on the first test drive. Make sure you put at least a few quarts in and then start the engine and let us warm up. Check the fluid, add fluid to fill it and then run it through the gears and check it again.

If your pressure is correct once the unit is filled, then you can go for a test drive.

Thanks very much for these tips. I really appreciate how you guided me to troubleshoot what was wrong. Can you recommend a place to purchase a rebuild kit or a respected company that sells these?

You are welcome. You can go with most any of the common sources like RockAuto or even a parts store like O'reilly's as they are pretty standard these days.

Here is a link to an online source that is pretty good because it lets you select what you want in your kit over and above what the other basic kits offer:

https://www.oregonperformancetransmission.com/product/OPT-AX4N-RB.html

However, if you just want a master rebuild kit then that would be most of what you need. There are sometimes that you need to source things that are not in the kits but that is rare.

Hey Kenny, I just want to let you know I have not given up on this. The weather is now getting warm enough for me to be able to work on this car in my unheated garage. I am wrapping up changing all the AT and coolant rubber hoses seeing they are easy to get to now. I ordered the rebuilt kit from Oregon performance and will soon be attacking the rebuild. Thanks! Hugh

Sounds great. We will be here whenever you get back to it.

Thanks for the update.

Hi Kenny, I am working on replacing all the rubber hoses for transmission oil and power steering cooling. Some of the original connections were hydraulically crimped. What are your thoughts on replacing those connections with the items in the picture? I went to our local hydraulic tube/rubber company, and he thought it would be okay for low pressure (i.e. 30PSI and lower) but hesitated to recommend this for higher pressure such as the high-pressure power steering line. What is your opinion, my friend?

They are exactly correct. That will be fine for low pressure. High pressure power steering lines can get up to 220 PSI so the hose clamp will just blow off. Those need a mechanical connection such as a press crimped line with a threaded connector.

I am getting ready to exchange the clutch units. Are all the clutches and steels the same thickness? Do I need to be concerned with a particular order, or are all the clutches the same? I know I have to soak the clutches in ATF.

Yep. They are all the same, so you don't have to worry about the order. Just they alternate steel, clutch, steel, clutch, and so on. The exact same order that they came out, just use the new ones.

You do not have to soak the seals, but I would soak the clutches in transmission fluid for at least an hour. Separate them so that the fluid coats them evenly.

I notice this part in my mix with transmission parts taken from this car. I cannot remember physically taking this off when disassembling. I searched the transmission rebuilt pages and could not find this part (it could be in these pages, and I just could not tell). In your experience, do you believe this is a transmission part?

It is hard to tell for sure but is that a spring/coil of metal? If so, that is the interior spring or support of a seal. It looks like what would be in an axle seal.

However, I don't think that was a part inside the transmission so I think you will be fine to continue.

That makes perfect sense. It probably came out of a crankshaft seal I replaced.

Yep. That would have one of those. Thanks for sticking with us.

Let us know how you make out when you wrap this up and if you have other questions.

Thanks