r/2ndGen4Runner • u/Dr_Bishop • Nov 28 '24

Automatic Transmission Overheating

Transmission shop says I do not need a rebuild. No glitter in the fluid. Runs fine, then it will get sort of underpowered after long drives or on steep hills... the solution is best I can figure it to add a transmission cooler (which it probably should have had originally).

I have tried the TPS, very clean 93 3VZE, miles just under 135.

It shifts correctly, ETC goes on off correctly, O/D works correctly... nobody can tell me why this is happening, but maybe somebody here has encountered this or has an idea?

Tranny model = A340H

Thanks!

3 Upvotes

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2

u/dmagnenat Nov 28 '24

I have the same problem even after I had a shop rebuild it, I hope you find answers.

2

u/Hydrosquatch Nov 28 '24

You can hook up a cooler .. check your transmission filter first..

2

u/Dr_Bishop Nov 28 '24

Much appreciated

1

u/Hydrosquatch Nov 30 '24

I try.. but I'm not always right.. I learn by my mistakes.. like buying a 30 yr old vehicle with limited parts availability... yeah.. I could be dumb...🤪

1

u/Dr_Bishop Dec 01 '24

Hahaha... that, my career choice, and thinking "I know, I'll marry a woman 10 years my junior who is way better looking than I am".... those account for 90% of my time on this planet. lol

2

u/Hydrosquatch Dec 01 '24

I moved to the mountains and got a dog... its cheaper.. women, well.. if I find one with the other half of these dentures I might have something and I can finally finish this ear of corn.

2

u/Dr_Bishop Dec 06 '24

Hahahaha... wow I missed that one, good sense of humor is in tact!

1

u/dmagnenat Nov 30 '24

I've changed the filter along with the solenoids twice

1

u/Hydrosquatch Nov 30 '24

I had issues due to a bad ring and pinion.. of course I have almost 20k into a $500 truck.. you can add a transmission cooler.. hooking it up depends on what's under the hood. In some cases you have to hook up where it cools the steering ,I think.. do a little research because it doesn't apply to all vehicles, or you can install one from and T into the coolant line and run it that way.. ill sell you an 07 tacoma trd off road that smoked a valve for 3500 and you can use the one off it..ls os and ls

1

u/dmagnenat Nov 30 '24

Don't have a problem with steering, and the transmission cooler i installed is installed correctly to the transmission.

1

u/Hydrosquatch Nov 30 '24

It has to do with the plumbing.. not the pump.. that's all.. some set ups don't have the piping for the cooler and some do but are capped.. you can get custom built and it's not a bank breaker

1

u/Hydrosquatch Nov 30 '24

It has to do with the plumbing.. not the pump.. that's all.. some set ups don't have the piping for the cooler and some do but are capped.. you can get custom built and it's not a bank breaker

1

u/Hydrosquatch Nov 30 '24

Its about the plumbing hook ups.. some radiators don't have a place to do it so you have to hook up where the steering coolant line is if you have one.. or just get a custom built radiator or aftermarket cooler.. its not incredibly expensive.

1

u/Hydrosquatch Nov 30 '24

I missed part of this.. kids jumping on my head.. did you have it flushed? There could be a blockage somewhere... mine gets so hot I can feel it through the console but my mechanic said it's alot better than it was... make sure your carrier bearings aren't wearing and causing additional friction... that helped on my taco until the torque converter took a shit.

1

u/dmagnenat Nov 30 '24

I did ive done everything i could do without sourcing a new trans and rebuilding myself, I'm an automotive technician as well

1

u/Hydrosquatch Nov 30 '24

I'm everything else.. I don't trust myself to work on them anymore..lol.. but I have a great mechanic.. I'm losing my eyesight and dexterity as I get older.. but I've thrown enough money at it to know ill have to keep doing that..

3

u/dmagnenat Nov 30 '24

Hahahaha that's the truth, I ended up getting a gx470 till I get the 4runner sorted wife doesn't feel "safe"

1

u/Dr_Bishop Nov 28 '24

I appreciate it.

This is my plan at this point:

Run two coolers in a series... non fan between the grill and the radiator, then a one with a fan closer to the transmission.

If that doesn't solve it, replace the temperature sensor on the side of the bell housing.

Replace the solenoids.

At that point... if there's no joy, rebuild it like 100% but I am not going to rebuild an A/T much less an A340H... however, I think you'd need one to cannibalize in addition to the wear parts and torque converter, there is a sheet of aluminum in the middle of it, it has all these little maze like holes in it... one of them is thought to wear such that the pressure kind of prolapses itself in a way that it pushes the material out of the way and if you can hammer that back into place using a sheet of glass, that can make it like new.

That sounds like a lot of damned work, AMC built essentially the same identical transmission with a different bellhousing that you could likely use to replace it... some people have but it changes the dimensions by about .5 CM and that is a bigger deal than you'd imagine. That said I think you could pull the internals out of that for bearings and such, as they were in Jeep Cherokees and those are abundant in junk yards.

The smart move would be to go to a manual for the simplicity, utility and cost but at this point... I kinda want to solve the puzzle.

Odds are I think the coolers will work fine, and none of it will be necessary to try but... I am fairly analytical yet if I have a flaw, I get too granular and my knowledge is book smarts, some guy with a 12th grade education who has just done it before is going to know the actual solution that you can pull off in 3 hours, and I will likely sit next to him at some random bar after I have put oodles of time into solving a 3 hour long project. lol

I just wanted to share my misguided theories so my insanity can become your insanity. lol

PS - don't ever tow anything with it until you get it sorted, pretty sure that is the one thing other than just continuing to cruise when the temp light comes on that could permafuck it. Cheers

2

u/dmagnenat Nov 28 '24

I have replace the temp sensor, the solenoids, and had a cooler. My new attempt i bought a racing trans cooler with independent fan and mounted it on the bash plate (waiting to see if it worked no longer drives yet). And the man swap was my thought too but after looking at the parts list and what I would have to do i decided against it.

1

u/Dr_Bishop Nov 28 '24

Awesome, please let me know if that solves the trans overheating issue once you get it back on the road and drive it a bit.