So my AT transmission with about 210k mi has been slowly getting worse despite my attempts to help it along.

Here are the symptoms:

1. Hard shifts.
2. Recently get some slipping while going up hill under heavy acceleration.
3. When braking to a stop, I hear/feel a thud as it shifts into first
4. When stopped with tranny in reverse, I hear a slight screech if I get under the truck.
5. When accelerating with a heavy load on engine/tranny, it will thud when I let off the gas to go to coast.
6. After slowing enough to get tranny into first gear, engine will rev before going back into gear when getting back on gas.

Here is what I have done to help it along:

1. Drain/fill tranny fluid with Dex 3 at each oil change to slowly get totally fresh fluid in.
2. Added a bottle of Lucas stop slip (Did before slipping started but after hard shifts and rest of symptoms started occuring.
3. Filter/magnets were cleaned before any symptoms occured. (Probably at 150k mi or so) Also before I started repeated drain/fills and lucas stop slip.
4. Lube driveshaft at every oil change.

I plan on dropping the pan one more time and cleaning the filter. But I have a question about the filter. I think I read that you can get just a replacement screen from autozone, is this true? I got a quote on a new filter from the dealer and it was 50 bucks. I will try cleaning/replacing the screen before buying a new filter at that price.

If that does not work, I need some advice on what to do next... Is it worth taking my truck into a good transmission shop or is there probably nothing they can do other than a complete rebuild/expensive fix?

I guess my other option is to get a used tranny off car-parts.com. I am a little apprehensive to go this route because I don't know how that works... Do the recyclers usually test trannys to make sure they are in good working condition? I see I can get a matching tranny with under 20k mi for less than $1000. I also want to find out if I can swap in a tranny from a newer year 3rd gen as well but I guess will start worrying about that later.

Oh, one more thing, is it possible for bad brake cylinders ( I think that is the name of the thing that pushes the brake shoes against the drum) to cause some of these symptoms or at least the very least, make them seem more pronounced?

If anyone cares to discuss, I will appreciate it very much!

 

Try tap recycling (www.taprecycling.com or www.fresno-taprecycling.com) They deal solely in used yota and lexus parts from damaged vehicles.

 

Thanks for the info on TAPRecycling. I will remember that if this comes down to needing a new tranny. Hopefully it won't but I am not too optimistic at the moment. Oh, and I don't think I am getting a vote of confidence on having my tranny repaired based on that post...

 

There is some talk that on 2wd models (no zerk points) binding rear brakes/cylinders can produce the "thunk" from moving from standstill/reverse into drive. The rear brake issue sometimes happens when the inner or outer axle oil seal fails washing the drum with diff oil. Have a look underneath or pull off the hubs.

 

Axle seals should be good as I replaced them along with the bearings last summer after they both leaked. I changed the shoes as well. I did not change the cylinder or drums though. The drums could possibly be out of round because the brakes were sticking but I don't feel any pulsing after doing that job.

 

Have you greased all the zerks?? If so, you should go to the tranny shop for a diagnosis

 

Sure have. If cleaning/replacing the filter doesn't help and nobody tells me otherwise, I guess taking it into the shop will be my next step. I just don't want to pay to get a diagnosis and then have to swap in a tranny regardless. But maybe it is worth it to have them tell me I need a new tranny rather than just assuming it on my own.

 

So I finally got around to dropping the pan and putting in a new transmission filter yesterday and boy is my tranny thanking me!

I used a filter from Autozone which was about half the price of the Toyota part. It definitely looks inferior to the Toyota filter but it is obviously doing a better job than the original filter.

I am happy to report that it feels like the torque converter is doing its job now. Shifts are MUCH smoother and getting on the gas after braking hard is much smoother as well.

Sometimes it doesn't want to go back into gear immediately after coming to a hard stop but I might just need to add a bit more fluid since I believe dropping the pan probably drained more than the normal draining does.

 

Fluid level, hot and idling, is critical to the A340 transmission. Needs to be checked on a level spot. Do this first.

I have had good luck with TransX which cleans the inside of age related slime and makes the valve body more efficient.

That transmission is a very common platform. The overdrive hub tends to wear out and causes the pressure to all the clutch packs to drop which induces slipping. Since its right behind the pump, the transmission can be dropped, pump pulled and a new OD hub can be replaced. But, go that far and you may as well rebuild the transmission. Probably $2000.

Hopefully getting the fluid level exactly right will cure the slipping.

My $0.02

 

start using amsoil, redline or M1 for the dexIII.. much smoother shifts beleive me. and start saving for a new tranny lol.. dexIII is crap. did you clean the original tranny screen? or just replaced it? you shouldnt have to buy a new one. most clean the screen

 

Try to find a wrecked 4runner of your year somewhere. Then take it, grab the tranny and other things you may want on it, and part it out on here to make some cash!

 

mkgarrison, I think I may switch to a branded name ATF in the future. I actually just went with a walmart brand since a lot of people I talk to say that any Dexron III formulated ATF pretty much the same.

I did clean the screen the first time I dropped the pan at around 120 k miles but decided to just replace the entire filter this time. Replacing the filter seems to be the way to go to me.

Anyway, I am thrilled to say that after topping off the fluid level, it shifts as good as a tranny with 215 k miles is going to shift. Thanks for all the replies!


P.S. mkgarrison, what are you the synthetic fluid police or something, LOL? I appreciate the comments you make but I am wondering what kind of experience you have with the stuff. Are you a mechanic or are you speaking from experience with your own vehicles?