Transmission- 5 Speed automatic write up with pics for second gen 4 liter trucks

@Sawbill I've been told they go pretty long with even these symptoms. I just need the fluids a new rear seal and a whole undisturbed weekend. it's hard when your half military and half government contractor. BTW are you running oversized tires as well?

 

@gearcruncher,
Thanks for keeping us in mind. I'll try to answer your question. 31K miles since the last pan drain and refill on mine. Service history prior to 197K miles is pretty meager. Toyota shows oil changes at regular intervals since day one, but nothing else. Don't know if Toyota's financing during that time (for 2 owners) had anything to do with the missing information or not.

I read through your linked page at the Sonnax site. Identified a worn lockup control plunger valve as the main cause of my RPM surge issue. Sonnax includes this in their Zip Kit. Because I'm planning to have RatioTek springs put in, I'll be going with a new OEM valve and sleeve to ensure overall compatibility. If you think I should replace any other parts in the valve body let me know.

I have a question as well: Do you know why running the air conditioning amplifies my transmission issues?

 

Garrett,
I hope you find the time soon. I know I never will. I'm not running oversize tires now. Might go with the tallest size I can use with stock suspension when the time comes. New tires are on my to-do list, but I've got a few gremlins to chase down before I can get to that.

 

I beleive you have mutliple issues not only with your transmission ,but your engine as well . When your AC is on ,Your engine is working much harder as the engine load is higher . Keep in mind that the air conditioning motor has 6 small pistons within the metal housing that you are now asking your engine to turn
When the computer in your truck commands the torque converter to apply and save you fuel , you are going to feel everything your engine is working at because that lock up clutch inside the torque converter locks the engine directly to the transmission .
If you are driving down the road at 40mph with the torque converter locked and the ac running , you will feel every stumble or missfire the engine has . Running the AC will amplify missfires .
Keep your right foot on the gas pedal and tap the brake pedal gently with your left foot when you feel surging . This test unlocks the converter clutch . I will bet the stumbling or surging goes away for a couple of seconds .
Do a stall test in your driveway with the engine warm to determine if you have an engine missfire problem . What RPM do you feel the surging at ?..This is very important ?
Before purchasing a bunch of transmission valve body parts , you should perform a stall test .
The procedure is on the first page of this post. Dealerships have a tendency of skipping the basic tests and jumping to conclusions and just want to sell you a new transmission . The days of proper diagnosing are long gone . We will try and save you some cash here my friend .
Post back the results of your stall test and we will go from there

 

Thanks gearcruncher. Since @Locoluna825 is having similar issues, your advice is gonna get around.

The RPM surges occur when the transmission downshifts while I'm coasting. As the tach needle falls to just above 1000 RPM I'll see a sudden drop to 500 RPM, followed by a quick spike to 1300 RPM, and then a slower drop below 1000 RPM where it settles down. This is without touching the gas pedal. Sometimes the needle ricochets wildly, other times it does a lazy bounce. Braking hides the problem.

I started to suspect engine-related factors when I was writing my first post here. After reviewing the records, I know the throttle body hasn't been cleaned in 69K miles and the spark plugs haven't been changed in over 70K miles. Might as well plan to get those 2 things done ASAP. Hadn't thought of it earlier because the truck was running pretty well and hasn't thrown any codes.

The tests will have to wait a couple of days. We're getting hit with waves of thunderstorms here and my truck is too tall to clear the garage door. Meanwhile, I'll check into getting a set of plugs.

 

Less than 48 hours after I wrote no codes, the truck decided to chastise me with a CEL.
The VSC Off and VSC Trac lights also came on.

Went to AutoZone for a diagnostic scan. P1441 came up twice on Bank 1 and P1444 came up twice on Bank 2.
These codes indicate a known problem on Toyota truck engines: Although it gets mixed reviews at TW, this might be the best solution for my 4.7: https://hewitt-tech.com/store/

I did manage to source NGK 3764 Iridium IX spark plugs on eBay. Price seems to vary depending on where they're manufactured, so more research required on those. My shopping list is getting longer and now includes a one of the plug and play kits referenced above, spark plugs, the mild RatioTek kit, 7 quarts of MaxLife ATF, 10 oz. Lubeguard Platinum, filter & pan gasket, and very possibly a new OEM lockup control plunger valve and sleeve.

The modest cost anticipated in my first post has morphed into something else. I've got no choice but to divide my list in half and start with the HT pnp kit and the spark plugs, which I should be able to do myself when time and weather allows. Feedback welcome.

 

@Sawbill keep us updated, would really like to know how it turns out.

 

I am looking for a picture of the square spindle that my Neutral Safety Switch goes on in the transmission. I have a 2007 Tacoma 4x4 A750F tranny ID. I am having a tough time figuring out if the spindle has the old part left on it or is it supposed to be threaded like this: https://youtu.be/pFt6n1FpJAg

 

That threaded portion is suppose to be there to hold the new switch in place . Use emery cloth or a grinder with a wire wheel to clean up the shaft . Once the shaft is clean , hit it hard with anti seize before you put the new switch on .
Google is your friend . Should be all kinds of images of what the shaft looks like when its new

https://www.scribd.com/document/18857706/T-SB-0277-09

 

Thanks brotha! Do you know the technical name of the spindle?

 

Most transmission guys call it the lever shaft . That shaft goes right through to the other side of the transmission .

 

Yeah..just a guess...but you might need a new one after looking at that picture

 

So my 2012 Tacoma developed the shutter/chatter at 40-45 mpg just after the first ATF flush at 125k miles w/ Valvoline MaxLife. No metal shavings in pan or filter and fluid still looked good. Only 2WD and never used for towing. I added the max dose of Lubegard and double checked my levels at the right temp using my Scangauge II. Still the Torque Converter shutter/chatter is there under very light acceleration at 40 mph. I'm not getting any codes from the engine or transmission.

I haven't done the brake switch test yet. I did replace the spark plugs and cleaned the throttle body and Mass airflow sensor. Took it to a trusted tranny shop and the owner diagnosed it as likely being a bad TCC Solenoid so I purchased part # 35280-30050 and had him replace it but the problem still persists. (Cost me $300 for parts and labor) By the way, is this the SLU solenoid? The tech called it the TCC solenoid.

I have it scheduled to flash the ECM tomorrow at my local Toyota dealership at a cost of $119. This is was the action associated with TSB 0044-14 to address spark knock noise. Am I correct that the newer flash of the ECM code adjusts the shift points to keep 5th gear from engaging too early? The shutter/chatter only occurs in 5th gears at around 1000 rpm and very light acceleration. As soon as you give it more gas it goes away or also if I downshift to 4th it goes away. Is there a good chance this ECM flash will help or is it a total wash of money? Does the ECM control the Transmission too?

If that doesn't help then I may try the Ratiotek Shift Improver Kit along with a "conservative" 1/8 clockwise turn of the screw under the SLU solenoid to increase torque convertor application pressure.

Is it a bad idea to turn the SLU screw at the same time the Ratiotek is installed? Sometimes if you make 2 changes at the same time you don't know which one is the cause the solution or the problem. I just hate to have to keep removing the pan. I have to put a new gasket on each time, right? Plus new crush washers?

Am I missing anything? Any suggestions would be appreciated.

 

Get the flash done first by all means . I would have started the repair with the flash first becuase its a serious known problem with the 2012 series Tacoma . Its worth spending the cash if your truck qualifies .Check you vin # for verification . Guys were having issues when these 2012 trucks were brand new and needed the flash within a few months of ownership . I can only imagine what you are feeling at 125k .
How long have you been feeling the chatter ? Does the chatter only occur when the converter clutch is applied or do you feel chatter as you are driving in 5th ?
Once the flash is done and if you still feel chatter which I doubt , do a brake switch test using a quality scanner .
Did your transmission tech use a scanner while driving the truck to diagnose the SLU ????? Proper diagnosis is the key here .
Could have saved you 300 bucks
The torque converter solenoid inside this transmission is the Switch Lock Up solenoid or SLU . Guys who have been working on these units forever call it the TCC solenoid or torque converter clutch solenoid .
Whenever you pop the pan off , you should replace the gasket .Replacing the crush washers not so much .
The ratio tech kit increases the converter clutch apply pressure using a different method . That being said , follow the instructions that come with the Ratio Tech kit

 

He diagnosed it with just a test drive with me in the vehicle. He referred to it as feeling like you're driving over rumble strips. He said it was most likely the TCC/SLU solenoid but probably didn't know the specific history on this 2012 with the TSB. I guess it's not a total waste of money since at least I now have a brand new TCC/SLU solenoid. They do wear over time right?

I did also notice the same shutter/chatter under light acceleration around 60 mph. It's not often it even gets to that speed since it's used mostly for local errands.

I'll report back tomorrow after the ECM flash is applied.

 

I wouldnt be touching the trans until he gets the engine working correctly . I will even bet once the engine is tuned , all his transmission problems will go away .
This is very very common .
Owners beleive the transmission is shuddering or the torque converter is chattering during upshifts or when the SLU solenoid is commanded on by the pcm .
The owner spends a bunch of cash trying to stop the shuddering or chattering only to find out that its not a transmission related problem but an engine issue creating a transmission symptom .
Proper diagnosis is the key .
The key is a quality scanner and a road test !!

 

OK, I just returned from the Toyota Dealership and they said I already had the latest ECM code. I was told it was 30455100. I recorded the service visit with my GoPro just to be safe and yep I heard the guy say I already had the latest version shortly after he connected his laptop and ran some diagnostics.

Anyway, on the way home I did the "tap" brake test at around 40-45 mph just when the shutter started and the shutter immediately ceased combined with a slight uptick of around 100-200 rpms. The shutter, which kind of feels like driving on rumble strips, comes back within a few seconds. This occurs around 1100-1200 RPM's only when in 5th. I know I am in 5th gear because if I manually put it in 4th then the RPM's are closer to 1700-1800 at 40-45 mph. So does this mean I have torque converter lock up clutch shutter? If so, what is causing it?

So what would be the next course of action? Is this something I can just ignore or is it causing damage and wear as a result? I want to get it fixed because it is annoying but seems to be isolated just to 40-45 mph under very light acceleration. The service tech said maybe it was u-joints but I highly doubt it.

 

OK, I think I'm gonna move on to installing the RatioTek Shift Kit. Should I get the standard kit or HD kit? I don't have a supercharger and my Tacoma is only a 2WD so I don't use it for towing or off-roading. Is there any benefit to the Heavy Duty kit in my case?

Also, I figure I might as well replace some other things while it's opened up. I can get the Sonnaz Zip Kit for only $210. Is this overkill? Tranny has 126k miles on it.

 

@Jamers99
No, i dont think it would be the u joints. I really doubt that. not if you're getting no shudder with it 4th.

I have the 5th gear, low speed shutter too. only happens in 5th. brake test confirmed, when I shift to 4th it stops.

I also had a u joint driveline rumble at 75-80 mph and it didn't make difference with whether or not it was in 5th of 4th. at first i thought it was old tires. but after a fresh set of tires it was still there. I was convinced it was the driveline. i have a Jeep wrangler background growing up, it behaved, sounded and felt like a driveline issue. The u joint was totally a speed thing in my case. luckilly, there was a warranty extension for my year tacoma up to 10 years for the driveline!! I got all my u joints replaced at about 201,000 miles for free! no more 75-80 mph driveline rumble.

I am still to this date dealing with 5th gear, low speed shudder at appx. 210,000 miles now. I bought both the sonax and ratio tek kits and i am still hesitating to pull the trigger on the install. the truck just runs too damn good, and am afraid to kill off the transmission with a mistake i may make on install. i'm considering doing the install to a low mileage donor transmission then perform a swap.

 

Update. So yesterday afternoon I went to drive up to the store and the truck wouldn't shift beyond 3rd gear. This is the first time I have ever experienced any shifting issues. So I went home and checked the codes and it was showing P0776 which indicates the Pressure Control Solenoid "B" is OFF. Just had the TCC/SLU solenoid changed on Tuesday as I stated in post #213 due to Torque Convertor Shutter.

I wonder if the SL2 solenoid was the problem all along and it just finally died completely? Anyway, I guess I'll be replacing the SL2 along with the RatioTel and Sonnax Zip kit install.