A442F Transmission problems.

[FJhammer]

Posted this over on the 70 side and have gotten zero traction, I figured since the A442 transmission was used in diesel 80s, I might try and see if anyone over here has any experience with what I'm seeing because I'm out of ideas. I recently imported an HZJ74 with the A442F automatic transmission. After importing, I drove it across a couple states, put approximately 1k miles over about 2 months and everything was working great. It's a super clean gem with only 84K miles on the clock and in terrific condition. As I proceeded through doing a baseline and replacing all fluids as I typically do, I ended up getting around to doing a drain and fill on the transmission. Immediately afterward, the transmission was no longer fully operational. When put into drive, you only have access to 3rd gear (possibly 4th, it's hard to tell). If 2nd is selected, there is no change. If L is selected, it will go into first with no issue. It will also go into reverse with no issue. Shifting back into D, you are then again limited to 3rd gear only. From a stop, if you start out in L and then shift to 2 or D it will bypass 2nd and immediately go into the 3rd. Overdrive is also lost. 2nd start also has no effect.

Again, prior to the drain and fill, the transmission worked great and was driving around with zero issues. Smooth sequencing through all the gears, no slippage, no flaring, no shuddering. I'm at a bit of a loss here on why it's not going through the gears, why it will let you do 1st if manually selected, or why it seems to want to stay in the upper gear. Pulling the pan, the magnets are clean and not a spec of glitter.

Things that I have tried.
Replaced solenoids and transmission filter with brand new OEM
Pin to pin continuity check
Transmission speed sensor replaced
ECT computer swapped
All grounds have been checked and cleaned

None of these have changed the symptoms at all.

Has anyone had this experience or know of someone that has? If so, what ended up fixing the problem? My next shot in the dark will be to replace the valve body, but again I'm just guessing at this point.

 

[robnicko]

what fluid did you replace it with, Dex II or III is what they like

 

[TheBussman]

Posted this over on the 70 side and have gotten zero traction, I figured since the A442 transmission was used in diesel 80s, I might try and see if anyone over here has any experience with what I'm seeing because I'm out of ideas. I recently imported an HZJ74 with the A442F automatic transmission. After importing, I drove it across a couple states, put approximately 1k miles over about 2 months and everything was working great. It's a super clean gem with only 84K miles on the clock and in terrific condition. As I proceeded through doing a baseline and replacing all fluids as I typically do, I ended up getting around to doing a drain and fill on the transmission. Immediately afterward, the transmission was no longer fully operational. When put into drive, you only have access to 3rd gear (possibly 4th, it's hard to tell). If 2nd is selected, there is no change. If L is selected, it will go into first with no issue. It will also go into reverse with no issue. Shifting back into D, you are then again limited to 3rd gear only. From a stop, if you start out in L and then shift to 2 or D it will bypass 2nd and immediately go into the 3rd. Overdrive is also lost. 2nd start also has no effect.

Again, prior to the drain and fill, the transmission worked great and was driving around with zero issues. Smooth sequencing through all the gears, no slippage, no flaring, no shuddering. I'm at a bit of a loss here on why it's not going through the gears, why it will let you do 1st if manually selected, or why it seems to want to stay in the upper gear. Pulling the pan, the magnets are clean and not a spec of glitter.

Things that I have tried.
Replaced solenoids and transmission filter with brand new OEM
Pin to pin continuity check
Transmission speed sensor replaced
ECT computer swapped
All grounds have been checked and cleaned

None of these have changed the symptoms at all.

Has anyone had this experience or know of someone that has? If so, what ended up fixing the problem? My next shot in the dark will be to replace the valve body, but again I'm just guessing at this point.

sorry but i have to start at the basics, how do you go about checking the fluid level? what did you put it in? did you change just the fluid or the fluid and filter? do you see alot of foam on the dipstick now?

 

[Broski]

The A442F also came in the 93-94 1FZ 80s
What you describe is very common solenoid
Issue.
Like to the T
I know you said you replaced the solenoids but I would double check them all 4 of them !!

I know that on my 94 that was the issue
The A442F is a very robust unit that you rarely hear of them going bad. When there is an issue, it’s almost always this solenoids.

 

[PIP]

Your symptoms sound like EXACTLY what happens when you don't read the dipstick right and don't get it filled up properly. How much fluid are you putting in it? They take a lot. And it takes awhile to get it through the tiny dipstick.

 

[FJhammer]

what fluid did you replace it with, Dex II or III is what they like

Toyota T IV

 

[FJhammer]

sorry but i have to start at the basics, how do you go about checking the fluid level? what did you put it in? did you change just the fluid or the fluid and filter? do you see alot of foam on the dipstick now?

No problem, I love the basics and really hoping it is something basic I'm overlooking.

- Fluid is checked off of the dipstick.
- I believe the specs called for Toyota's T IV fluid, and that's what I used.
- The first time, I just did a drain and fill. I tried a second drain and fill, same result. Third time I pulled the pan, checked the magnets, replaced the filter and the solenoids.
- I don't see any foam on the dipstick.

 

[PIP]

- Fluid is checked off of the dipstick.

Explain more please.

It's nowhere near that simple. You have to put 4-5 quarts in it. Start the engine, run through the gears, shut it off, add more quarts, allow plenty of time for the fluid in the dipstick to settle, then start the engine and read the dipstick with the engine running in park.

If you did something very close to that and you're confident fluid level is good the next troubleshooting step is the unplug the wiring from the trasmission and take it for a drive. If it is a solenoid or electronics problem you can drive the transmission fine by manually shifting through the gears.

 

[FJhammer]

The A442F also came in the 93-94 1FZ 80s
What you describe is very common solenoid
Issue.
Like to the T
I know you said you replaced the solenoids but I would double check them all 4 of them !!

I know that on my 94 that was the issue
The A442F is a very robust unit that you rarely hear of them going bad. When there is an issue, it’s almost always this solenoids.

That was my conclusion after doing a bunch of research as well. According to diagnostic chart I found, it looked exactly like the symptoms of a #1 solenoid failure, but I just decided to replace them all just in case... hence plopping down $600 on new OEM solenoids. I would just find it hard to believe the new ones are failing in the exact same manner.

Before I open the pan and pull the new ones, I can check the old ones just to see if one of them actually was failing and go from there.

 

[FJhammer]

Your symptoms sound like EXACTLY what happens when you don't read the dipstick right and don't get it filled up properly. How much fluid are you putting in it? They take a lot. And it takes awhile to get it through the tiny dipstick.

I'm repeatedly draining about 5.5qts and putting the same back in. And yes, it takes awhile. Ask me how I know. Lol

 

[FJhammer]

Explain more please.

It's nowhere near that simple. You have to put 4-5 quarts in it. Start the engine, run through the gears, shut it off, add more quarts, allow plenty of time for the fluid in the dipstick to settle, then start the engine and read the dipstick with the engine running in park.

If you did something very close to that and you're confident fluid level is good the next troubleshooting step is the unplug the wiring from the trasmission and take it for a drive. If it is a solenoid or electronics problem you can drive the transmission fine by manually shifting through the gears.

So something similar to that. I drain it, measure what was taken out, replace that amount, start it and move the selector between each position, and then recheck levels.

Interesting. I will unplug the harness today and give that a shot. Thank you!

 

[dallen341]

Toyota T-IV is not a direct, recommended equivalent for Dexron III. While T-IV shares a similar viscosity profile and is largely backward-compatible with older Toyota specs, it contains specific friction modifiers designed for Toyota torque converters that can cause shifting issues or long-term wear in transmissions requiring Dexron III.

 

[PIP]

+1 for Dex 3.

 

[smorkington]

Properly check levels if its correct then I would pull solenoids and test them. Most modern atfs are backwards compatible I wouldnt waste the time or money swapping it out. Also you have a hydraulic controlled a442f which is different than the ones found is usdm fzj80s. If anything go to an international facebook group and ask there. Most diesels had hydraulic a442 they will know more than people on this site. If not you could try a local transmission shop while hydraulic a442f is rare in united states its an aisin transmission with simply architechure they could likely assist in diagnosing your issue.

 

[Malleus]

FWIW, if you're going to the trouble of replacing the fluid, replace all of it. You cannot drain and refill these transmissions the way you do your engine. You have to actually pump the fluid out, just like you do in the power steering system, for the same reason: there is fluid in the case, the cooler lines and in the torque converter. None of that comes out when you drain the pan. You can use the cooler lines and front pump to do this; you don't need any special equipment, other than a graduated gallon container and a spare hose of the same size as the cooler line.

Nevertheless, I have no idea which flavor of A442F the 70 was fitted with, but if it's electro-hydraulically controlled, it'll have a separate TCM. If it doesn't, it's hydraulically controlled, like the A440F, by a rear mounted governor.

IME, you cannot mix Toyota T–IV with Dexron III. You really need to pump all that fluid out and put Type III in. T–IV is, again IME, too thin for the transmission.

My best guess is that the higher torque gears are operating because they don't require as much pressure as the low gears do, and the thinner oil is sliding past the low gears' flow oil pressure path. Replacing the oil will solve that problem.

Bear in mind that you cannot get the oil out of the torque converter, unless you cut it open. It may take several flush and fill & drive at highway speeds where the torque converter can lockup, before it gets back to normal...unless you replace the torque converter, which I wouldn't recommend.

 

[TheBussman]

Properly check levels if its correct then I would pull solenoids and test them. Most modern atfs are backwards compatible I wouldnt waste the time or money swapping it out. Also you have a hydraulic controlled a442f which is different than the ones found is usdm fzj80s. If anything go to an international facebook group and ask there. Most diesels had hydraulic a442 they will know more than people on this site. If not you could try a local transmission shop while hydraulic a442f is rare in united states its an aisin transmission with simply architechure they could likely assist in diagnosing your issue.

he has a tcm and solenoids, it's exactly like the usdm fzj80 one.

 

[TheBussman]

are you checking the fluid level with the engine running? where is the level at? I'm sorry but need to start with the basics. it does sound like a low level.

 

[FJhammer]

he has a tcm and solenoids, it's exactly like the usdm fzj80 one.

Can confirm. I have a TCM (or ECT as its labeled in the truck) and the 4 solenoid setup.

 

[FJhammer]

FWIW, if you're going to the trouble of replacing the fluid, replace all of it. You cannot drain and refill these transmissions the way you do your engine. You have to actually pump the fluid out, just like you do in the power steering system, for the same reason: there is fluid in the case, the cooler lines and in the torque converter. None of that comes out when you drain the pan. You can use the cooler lines and front pump to do this; you don't need any special equipment, other than a graduated gallon container and a spare hose of the same size as the cooler line.

Nevertheless, I have no idea which flavor of A442F the 70 was fitted with, but if it's electro-hydraulically controlled, it'll have a separate TCM. If it doesn't, it's hydraulically controlled, like the A440F, by a rear mounted governor.

IME, you cannot mix Toyota T–IV with Dexron III. You really need to pump all that fluid out and put Type III in. T–IV is, again IME, too thin for the transmission.

My best guess is that the higher torque gears are operating because they don't require as much pressure as the low gears do, and the thinner oil is sliding past the low gears' flow oil pressure path. Replacing the oil will solve that problem.

Bear in mind that you cannot get the oil out of the torque converter, unless you cut it open. It may take several flush and fill & drive at highway speeds where the torque converter can lockup, before it gets back to normal...unless you replace the torque converter, which I wouldn't recommend.

Alright, since several people believe the cause is the T-IV in lieu of Dextron III, I picked up 16qts of the Dex and I will do a full swap from the cooler line as suggested. I'm a bit skeptical as manually shifting to low and reverse, it functions perfectly. But I'd rather spend $140 in fluid an afternoon and end up being wrong.

I just don't understand why it doesn't want to downshift automatically, especially when coming to a stop. However, if done manually it has zero problem. Riddle me this batman.

 

[Broski]

IMO if it shifts fine manually then it not the fluid.