First time poster, long time stalker. Need help diagnosing my A440 on my 89 FJ62. Tranny temps raise very quickly as I drive around town. If I’m able to get it up to around 55mph the temp will quickly drop but only for about 10 miles or so and it will begin to climb back up. Any ideas? Thanks.
A440f overheating
- Thread starter jmsilvr43
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
- Thread starter
- #3
Oil level is good. Not sure of the service. My dad gave me this truck about 2 years ago. Has an extra cooler and no issues other that the overheating. It runs strong otherwise.
How do you know it is over heating? I mean they do get stupid hot and the tunnel under you gets hot too. Is your trans temp light coming on?
- Thread starter
- #5
I have a gauge installed. The light on the tree does not come on but I’m not even sure that works. The gauge has gotten up to 260 though.
That does seem hot. So next time you are out if you have a thermal thermometer take it with you. When you stop check it with the thermometer against what your inside gauge is telling you.
Do you have stock tires? Stock ring and pinion gearing?
As old as our trannies are, there could be several reasons it's developing more heat. The fact that you've got a gauge and an external cooler is a good start. My gauge's top limit is 260*, same as yours. The factory idiot light would come on at 300* and go off at 280*, so stopping and letting your tranny cool when the gauge reaches 260 gives you a little more margin of safety. Reason yours isn't working is also likely the same as mine. I pulled the OEM temp sensor and used a die on the adapter that came from Autometer so that it would thread into the factory hole using the factory threads. So I sacrificed functionality of the idiot light for the benefit of a gauge. @Saucerman is right that these run very hot under normal conditions. If you're running larger tires (I've run 31" tires for 15 years as opposed to the stock size 28" tires) and stock gears that also puts a little more stress on the tranny when things aren't locked up, generating more during heat non-highway driving.
Best thing to do to gauge if your tranny is on its way out or not is to get a new pan and strainer gasket (you could also either order a new strainer or take the time and several cans of either B12 or Brakleen to clean the existing strainer (it's a metal mesh filter so it can be cleaned but is a bit of a pain). See how much (if any) clutch material is caught up in the strainer (it looks like spat out dip) and if there's a lot, that's an indicator your tranny is headed towards the end of its service life. Also give the inside of the pan a good cleaning and check and clean the magnets in the pan. There will be a little bit of buildup on the magnets from normal wear, but a lot of buildup is also a bad sign. Reinstall the (new or cleaned) strainer with a new gasket and reinstall the pan with a new gasket. Fill with new ATF (I HIGHLY recommend Schaeffer's All-Trans Supreme. I credit this with buying me an extra year when my tranny was going out and helping it run much cooler in the interim). Fill with one quart less than when you drained out, then cycle the transmission through the gears and check the cold level with the engine running, drive it around a while making sure it gets up to operational temps, check the level with the engine still running and the tranny hot, and if it's a little low top it up about a cup at a time until the level reads dead center in the hot range. For some reason these particular automatics are very sensitive to overfill or underfill.
One trick I learned fluid level wise is to measure how much you drain from the drain plug (let it drip out overnight if you can afford the time), then bearing in mind you're going to lose almost a whole quart more when you drop the pan and the strainer (be ready to get splooged on), when you refill you can put in the same amount you measured when you drained it from the plug and use that as a starting point.
Best thing to do to gauge if your tranny is on its way out or not is to get a new pan and strainer gasket (you could also either order a new strainer or take the time and several cans of either B12 or Brakleen to clean the existing strainer (it's a metal mesh filter so it can be cleaned but is a bit of a pain). See how much (if any) clutch material is caught up in the strainer (it looks like spat out dip) and if there's a lot, that's an indicator your tranny is headed towards the end of its service life. Also give the inside of the pan a good cleaning and check and clean the magnets in the pan. There will be a little bit of buildup on the magnets from normal wear, but a lot of buildup is also a bad sign. Reinstall the (new or cleaned) strainer with a new gasket and reinstall the pan with a new gasket. Fill with new ATF (I HIGHLY recommend Schaeffer's All-Trans Supreme. I credit this with buying me an extra year when my tranny was going out and helping it run much cooler in the interim). Fill with one quart less than when you drained out, then cycle the transmission through the gears and check the cold level with the engine running, drive it around a while making sure it gets up to operational temps, check the level with the engine still running and the tranny hot, and if it's a little low top it up about a cup at a time until the level reads dead center in the hot range. For some reason these particular automatics are very sensitive to overfill or underfill.
One trick I learned fluid level wise is to measure how much you drain from the drain plug (let it drip out overnight if you can afford the time), then bearing in mind you're going to lose almost a whole quart more when you drop the pan and the strainer (be ready to get splooged on), when you refill you can put in the same amount you measured when you drained it from the plug and use that as a starting point.
Your trans sounds like my old one. Swap it. Swap for an H55. That will solve all your problems. Trust me. I battled my A440 for years, sinking thousands into it. Swapping was the best decision I ever made.
Make sure the torque converter is locking. Should be about 2200 rpm @ 100kmph.
The trans can run hotter if the converter isn't locking.
The trans can run hotter if the converter isn't locking.
This is what I ended up doing. Picked it up from @torfab yesterday and LOVE IT. Still having to re-learn myself on driving a stick but it's coming back. I only stalled it twice while driving it around Everett and Snohomish yesterday
I am sure your stoked!!This is what I ended up doing. Picked it up from @torfab yesterday and LOVE IT. Still having to re-learn myself on driving a stick but it's coming back. I only stalled it twice while driving it around Everett and Snohomish yesterday
$1370 for the conversion kit from CruiserParts.net (shoutout), $2800 for the trans from Toyota, and $2600 for labor and additional parts. So, ya, about $7000. But, absolutely 100% worth it. I'm trying to sell you. I wish I had someone light the fire under me years ago. I would have saved every penny I could to get it done when I was in high school to have a truck that actually responded to the throttle, that drove over 50mph without needing an asthma inhaler, that could climb a hill, that I could trust to drive somewhere without needing AAA to drive me home. @Ocean15, I'm telling you, you'll have a brand new truck. For the first time in over 30 years, my truck doesn't need a truck diaper! She doesn't leak on the garage floor!!! Do you know what that's like!?! Sorry... I just feel a little strong about it...
Great Tonka - I'm sold! Your description of your pre-swap is all too familiar believe me. I'm on my second 440f (salvage) in the last 5 years and now my rear seal is starting to weep some so I don't dare park it in any friends driveway. Now if only this Covid situation will get resolved so I can get back to work and start saving for the swap then I'll get on it. I'd love to go for a ride in yours to see the difference!
Check out my build thread. Not just for self promotion, but to see my struggles and conclusion
Spook, what are the factory threads for the OEM tranny temp sender? Not 1/8NPT?
If I remember correctly I removed the pan, then removed the sender for the light and tapped its hole for a 1/8 NPT. It resulted in disabling the idiot light, but I didn't care since I had an actual gauge to use instead.
Edit: Just looked back in this same thread and saw I used a die on the Autometer sender to match it to the threads for the OEM sender hole. I searched to be sure and found this thread again
Last edited:
Thanks. I need to figure out how to keep the light...and add the gauge. I was hoping I could tee off the sender port and add a gauge sender....like we do for oil pressure. That way I can use the light to also trip an audible alarm. There must be a way.
I put a T in the cooler line [output flow] just before the external cooler for the gauge. Not ideal coz the fluid would probably drop a couple of degrees in the pipe. Seems to work ok, and I left the original sender where it is.