Hello friends,
I just did a service on my 1995 KZJ78 with the A343F automatic transmission. I've been chasing a shift anomaly and things were pointing in the direction of bad shift solenoid (s). So, I thought I might share this experience with you!
Disclaimer:
I did this on my own truck and may follow at your own risk etc etc.
Tools needed:
1. 14mm, 12mm, 10mm, 8mm sockets and a suitable rachet with a combination of extensions, I used a 5" and 2"
2. A 6 qt minimum oil draining pan
3. A torque wrench
4. Brass wire brush
5. Rubber mallet
Parts needed:
1. A gasket/solenoid kit that fits your version of the A343F. (Be careful as there are some differences). I bought these from eBay and Amazon based on visual matching and they were the right ones
HERCOO A340 AW4 Transmission TCC... Amazon product ASIN B07F2HM4W4
Supplies needed:
1. One gallon of your favorite ATF (I used the Valvoline Maxlife Full Synthetic ATF (Dexron II, III compatible)
2. A tube of suitable RTV. I used the AISIN AB127B1
3.. Razor/utility blade
4. Solvent (IPA/acetone/lacquer thinner etc)
5. Shop towels/hand/tool towels
Thing that makes life easier:
1. Oil changing tray
2. Puppy training pads. These worth their weight in silver!
Instructions:
First, if you haven't done it already, this is a very good time to do a full transmission flush. Check out my recent write up on how to do just that here
Now, check your ATF level cold. Should be within the lower two markings on the stick. Go ahead and setup shop on level ground, disconnect both negative battery terminals and remove the bashing plate under your transmission using the 12mm socket.
Place your oil changing tray lined with puppy pads, and situate the oil changing pan on top of the pads under the drain plug on your AT.
First (important) remove the AT dipstick as it will interfere with your efforts to drop the pan later. Using the 14mm socket, drain your ATF into the pan. Allow for extended drip time. When you feel like you've got most of what you can get out (4-5 qts), go ahead and replug the drain using a new drain washer, obviously.
Now, using the 10mm socket, remove the thousands of screws holding the pan in. Start with the harder to reach ones closer to the cross member to guage what combo of extensions would work for you early on. This is actually easy I'm just trying to be funny. When done, run your razor blade between the pan and the AT housing to cut through some of the old FIPG material (usually red or black ATV). Give the pan some gentle yet firm whacks with the mallet. And rock the pan to dislodge it from the AT, it takes some patience and more razor time but not too bad. Don't worry too much about the pan falling as it's light in weight and still sort of held up by the dipstick tubing (the dipstick tubing is made out of two pieces with an o ring in between).
The pan will come loose and this is when you book your oil spill therapy session for Monday. There will be some ATF dripping from the body of the AT, the filter, etc. Embrace the oil and use some shop towels to manage it. There are many liters of ATF hiding above but you shouldn't worry about that.
These puppy pads man! Even better than kitty litter
Using the 8mm socket, remove the filter screws and it will drop. and locate the three solenoids on the RHD passenger side of the transmission. You can't miss them. Each solenoid is held in place with one 10mm bolt. The solenoids are pressed (very loosely into their respective housing and are each connected with an small electrical connector. The two shift solenoids (1 and 2) are identical and interchangeable, the lock solenoid is a little different in shape so no drama in how to identify what goes where. (Remember, when you remove the filter and solenoids, some more ATF will come out, nothing much just annoying).
Fit in your new solenoids and clip their connectors on securely, and fit in your new clean ATF filter and its gasket (more of a strainer than filter).
The new filter, filter gasket, and pan gasket (rubber).
The least fun part starts now, start cleaning and prepping the AT pan by removing the old FIPG using patience and the razor blade. Take your time! Do a good job and leave nothing without damaging the mating surface of the pan. You can use the soft brass bush for some of the stubborn bits. When it's all clean and shiny, go ahead and clean the inside of the pan. Take note of the ATF residue there, the color, smell, and consistently. Mine had some sludge there but no identifiable metal shavings. There are four magents in that pan, clean them well and inspect what's stuck on them.
Tip: (when you put the magnets back, make sure the chamfered face is down towards the pan for better engagement with the pan surface as the other face of the magnet is slightly sharp and raised around the edge, which could cause the magnets to shift if it was facing the pan).
Here's the pan before and after:
Time to prep the mating surface of the AT. Using the razor, scrape from inside out so you won't introduce contaminants into the housing. This won't take too long but do a good job. Neatness counts!
Since at least some flavors of the 1KZ-mated transmissions came with an actual gasket for the AT pan and not just RTV like the case in the 80, 100 series, I decided to use the gasket from the kit but doubled down with a (very) light smear of FIPG between all the surfaces (before and after gasket). This was mainly because I don't have the exact FSM for the job, but managed to determine that the torque spec for the pan bolts was around 6.9 n/m. But I think this is might be for the non-gasket ones. I ended up going with 6 ft/lb torque.
The thin application of RTV before the rubber gasket
Now that everything is clean, wipe the metal faces with the solvent, conduct a sanity check, affix your gasket with the lightest of smears using your finger instead of laying a bead. This stuff dries rather quickly so go ahead and attack that pan up minding the dipstick tubing, of course. Drive in the screws loosely and ditch your rachet for the torque wrench. Torque up the bolts in an alternating/center out fashion (HG style) and then double check them all.
This is where you would pour in the same amount of ATF as you drained out using the dipstick port and a funnel. With a good light, check for any immediate leaks under, including the dipstick o ring area. When all is well, clean things up, drop the dipstick in for a cold measurement. Reconnect your batteries and go for a drive for at least 20 minutes post initial warm-up and your transmission should be shifting real nice like!
Upon return, double check for leaks while hot and check your ATF levels again. Now put that bash plate back on and you are done!
[Insert mandatory beer-related statement...]
This was a cheap and easy PM item that I would've have done even without shifting anomalies, but it's a step towards pinpointing the culprit... my next victim: the ECU... Keep an eye for an ECU rebuild tutorial here soon!
Cheers!
Moe and Tigris 3
I just did a service on my 1995 KZJ78 with the A343F automatic transmission. I've been chasing a shift anomaly and things were pointing in the direction of bad shift solenoid (s). So, I thought I might share this experience with you!
Disclaimer:
I did this on my own truck and may follow at your own risk etc etc.
Tools needed:
1. 14mm, 12mm, 10mm, 8mm sockets and a suitable rachet with a combination of extensions, I used a 5" and 2"
2. A 6 qt minimum oil draining pan
3. A torque wrench
4. Brass wire brush
5. Rubber mallet
Parts needed:
1. A gasket/solenoid kit that fits your version of the A343F. (Be careful as there are some differences). I bought these from eBay and Amazon based on visual matching and they were the right ones
35303-35010 A340H/AW30-80LE Transmission Filter Gasket For Toyota Pickup 4Runner | eBay
Find many great new & used options and get the best deals for 35303-35010 A340H/AW30-80LE Transmission Filter Gasket For Toyota Pickup 4Runner at the best online prices at eBay! Free shipping for many products!
www.ebay.com
HERCOO A340 AW4 Transmission TCC... Amazon product ASIN B07F2HM4W4
Supplies needed:
1. One gallon of your favorite ATF (I used the Valvoline Maxlife Full Synthetic ATF (Dexron II, III compatible)
2. A tube of suitable RTV. I used the AISIN AB127B1
3.. Razor/utility blade
4. Solvent (IPA/acetone/lacquer thinner etc)
5. Shop towels/hand/tool towels
Thing that makes life easier:
1. Oil changing tray
2. Puppy training pads. These worth their weight in silver!
Instructions:
First, if you haven't done it already, this is a very good time to do a full transmission flush. Check out my recent write up on how to do just that here
Now, check your ATF level cold. Should be within the lower two markings on the stick. Go ahead and setup shop on level ground, disconnect both negative battery terminals and remove the bashing plate under your transmission using the 12mm socket.
Place your oil changing tray lined with puppy pads, and situate the oil changing pan on top of the pads under the drain plug on your AT.
First (important) remove the AT dipstick as it will interfere with your efforts to drop the pan later. Using the 14mm socket, drain your ATF into the pan. Allow for extended drip time. When you feel like you've got most of what you can get out (4-5 qts), go ahead and replug the drain using a new drain washer, obviously.
Now, using the 10mm socket, remove the thousands of screws holding the pan in. Start with the harder to reach ones closer to the cross member to guage what combo of extensions would work for you early on. This is actually easy I'm just trying to be funny. When done, run your razor blade between the pan and the AT housing to cut through some of the old FIPG material (usually red or black ATV). Give the pan some gentle yet firm whacks with the mallet. And rock the pan to dislodge it from the AT, it takes some patience and more razor time but not too bad. Don't worry too much about the pan falling as it's light in weight and still sort of held up by the dipstick tubing (the dipstick tubing is made out of two pieces with an o ring in between).
The pan will come loose and this is when you book your oil spill therapy session for Monday. There will be some ATF dripping from the body of the AT, the filter, etc. Embrace the oil and use some shop towels to manage it. There are many liters of ATF hiding above but you shouldn't worry about that.
These puppy pads man! Even better than kitty litter
Using the 8mm socket, remove the filter screws and it will drop. and locate the three solenoids on the RHD passenger side of the transmission. You can't miss them. Each solenoid is held in place with one 10mm bolt. The solenoids are pressed (very loosely into their respective housing and are each connected with an small electrical connector. The two shift solenoids (1 and 2) are identical and interchangeable, the lock solenoid is a little different in shape so no drama in how to identify what goes where. (Remember, when you remove the filter and solenoids, some more ATF will come out, nothing much just annoying).
Fit in your new solenoids and clip their connectors on securely, and fit in your new clean ATF filter and its gasket (more of a strainer than filter).
The new filter, filter gasket, and pan gasket (rubber).
The least fun part starts now, start cleaning and prepping the AT pan by removing the old FIPG using patience and the razor blade. Take your time! Do a good job and leave nothing without damaging the mating surface of the pan. You can use the soft brass bush for some of the stubborn bits. When it's all clean and shiny, go ahead and clean the inside of the pan. Take note of the ATF residue there, the color, smell, and consistently. Mine had some sludge there but no identifiable metal shavings. There are four magents in that pan, clean them well and inspect what's stuck on them.
Tip: (when you put the magnets back, make sure the chamfered face is down towards the pan for better engagement with the pan surface as the other face of the magnet is slightly sharp and raised around the edge, which could cause the magnets to shift if it was facing the pan).
Here's the pan before and after:
Time to prep the mating surface of the AT. Using the razor, scrape from inside out so you won't introduce contaminants into the housing. This won't take too long but do a good job. Neatness counts!
Since at least some flavors of the 1KZ-mated transmissions came with an actual gasket for the AT pan and not just RTV like the case in the 80, 100 series, I decided to use the gasket from the kit but doubled down with a (very) light smear of FIPG between all the surfaces (before and after gasket). This was mainly because I don't have the exact FSM for the job, but managed to determine that the torque spec for the pan bolts was around 6.9 n/m. But I think this is might be for the non-gasket ones. I ended up going with 6 ft/lb torque.
The thin application of RTV before the rubber gasket
Now that everything is clean, wipe the metal faces with the solvent, conduct a sanity check, affix your gasket with the lightest of smears using your finger instead of laying a bead. This stuff dries rather quickly so go ahead and attack that pan up minding the dipstick tubing, of course. Drive in the screws loosely and ditch your rachet for the torque wrench. Torque up the bolts in an alternating/center out fashion (HG style) and then double check them all.
This is where you would pour in the same amount of ATF as you drained out using the dipstick port and a funnel. With a good light, check for any immediate leaks under, including the dipstick o ring area. When all is well, clean things up, drop the dipstick in for a cold measurement. Reconnect your batteries and go for a drive for at least 20 minutes post initial warm-up and your transmission should be shifting real nice like!
Upon return, double check for leaks while hot and check your ATF levels again. Now put that bash plate back on and you are done!
[Insert mandatory beer-related statement...]
This was a cheap and easy PM item that I would've have done even without shifting anomalies, but it's a step towards pinpointing the culprit... my next victim: the ECU... Keep an eye for an ECU rebuild tutorial here soon!
Cheers!
Moe and Tigris 3
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