Transmission Troubles-A750E

1/20/22 I recently purchased a 2006 Toyota Tacoma SR5 Prerunner TRD Offroad with a 4.0L and a 5spd. automatic transmission. It has over 225K miles on it and even though the original owner took very good care of it, by giving me a thick folder of recorded maintenance receipts, the truck would need work sometime down the road. Well it's that time and it happens to be the Transmission that giving me problems. It started with a shuttering or shaking feeling that I felt in the steering wheel. It would only happen when I took off from a stop and accelerated out of 1st or 2nd gear and it would happen twice, in a roll, for only seconds. It wouldn't happen every time, but it seemed when the engine was warming up. I did change the fluid, using Valvoline Max Life ATF, and a new filter and the issue seems to have gone away. Now I'm dealing with shifting and slipping problems. I'm experiencing the getting hit from the rear feeling and getting stuck in gear while passing slower cars on the freeway. Again, these problems don't happen all the time and after goggling the internet I was able to get some answers. My first thought was to get the transmission diagnosed but at $140 I might get a answer provided the electronic transmission computer had picked up problem codes. I haven't seen anything in the dash light up and was informed that it might not show up in the handheld code readers. Back to the drawing board, I'm told the valve body solenoids, seven in the A750E/F, maybe the problem. In regard to the rear-ending issue it maybe the SLT solenoid. So before I start testing these solenoids or replacing them, I'm going to add some transmission additive that should clean the possible sticky solenoids and shifting problems. I'll get back with the results asap.

 

Sounds like you are having some torque converter shudder issues. I have the one I pulled from my truck at 112k clean and ready to go. It comes with a torque converter. Pm if interested.

 

Have you looked through the thread below?
https://www.tacomaworld.com/threads...th-pics-for-second-gen-4-liter-trucks.289913/

 

Thanks everyone for the info., the shuttering seems to be gone after I changed the filter and tranny fluid using Valvoline Max Life. I keep finding new info. on the internet as I go, I found a complete set of solenoids, 7, and the wiring harness for just under $700.00. The SLT alone goes for $230 at the dealer. But I'm going to see if the additive works to clean out the solenoids and provide better shifting. I'm going this way first because it's the least expensive and the problems are intermediate.

 

Again, I have one fully functional in my garage( I removed it because I converted my truck to 4x4 and used a full A750F) let me know if you’re interested. Cheers

 

Thanks, but no thanks. If I do go that direction, it would be a remanufacture trans. All the upgrades and flaws have been addressed and at $2500 with a 6yr. unlimited milage warranty I can go wrong. Thanks for the offer.

 

Hurrah I was looking for 300 buckaroos and to give a second life to the good ol E. Cheers

 

Did the additives work and help with the solenoid issue? If so, what kind of additive did you add?

 

https://www.tacomaworld.com/threads...guide-for-dummies.716703/page-6#post-25712251 This is what I used.

 

No I haven't gotten around to that yet because I can't decide which one to use. There are quite a few products that claim to solve this, but not that. I had to take a break from trying to decide what to do, cleanse out the tranny with an additive, pay to diagnose the problem or just replace the whole thing? So I called a few friends and they all said to use Lucas Transmission Fix. It claims to clean and lubricate sticking valves for proper shifting. Bingo that's what I was looking for, I've used other Lucas products in my engine and rear axle so I trust this product. I plan on doing this tomorrow and will get back with the results.

 

Thanks! Looking forward to your results! Best of luck to you sir!

 

Hard shifting and not kicking down when trying to pass? Are you sure the fluid level isn't low?

 

I was just under my Tacoma today and I see no leaks since I replaced the ATF and filter a few months ago. The tranny shifts into a lower gear, probably 4th, to allow me to pick up speed to pass slower drivers but won't shift back up into 5th. If I slow down or come to a stop it does shift all the way down ok. It doesn't happen all the time so maybe when I put Lucas trans. fix in, hopefully it will solve the problem...temporally.

 

I have a 2006 with 218k miles 5spd auto and experienced the shudder issue. At first I did the flush and Instant shudder fix additive and the problem went away but after about 10k miles it reared it's ugly head again. Did the flush and Instant fix again and it went away but this time it came back sooner and stayed. The shuddering would not happen if I started out in 4th gear instead of drive which confirmed the problem was with the flex lockup in the converter. I thought about buying a reman A750 but decided to just replace the converter instead. I contacted Florida Torque Converters and they sent me one part# 89-90. Replaced the converter and ATF filter and filled with Valvoline MaxLife. Test drove the truck and tried my hardest to duplicate the shuddering issue and couldn't. Shudder is completely gone. 1000 miles on it so far and trans is shifting like new again. Before you go out and spend a couple grand on a remand A750 try replacing just the converter. $199 after core charge. The picture shows what looks like an A750F but it's actually an A750E converted to 4WD. They both use the same torque converter for V6 models.

Old converter

New one installed

 

Update-after rereading my Chilton manual I realized that I miss an important step while refilling the tranny, the engine needs to be on and idling. Also, it appears that the temperature of the ATF needs to be between 95 & 115. Normal engine temp. is 195 to 200 and my dash engine temp. gauge is normally in the middle, so what I did was to get everything read to go down below. Unscrew the fill plug, loosen the check plug, get the drain pan ready and ATF with pump. The Tacoma has been sitting all day and was cold so I started the engine and wait till it got near a quarter way and crawl underneath unscrew the check plug and start pumping the ATF in the fill hole as fast as I can while watching the check plug hole. I had to use two 24oz. bottles of Lucas tranny fix until the ATF came dripping out. I figured it was about a quart and a half low. I only had time to do that this evening and will drive it around tomorrow.

 

Use this as a guide to get it to the proper temperature. It is a drain and fill, but just skip to the fill part how to heat it up and fill properly.

https://www.tacomaworld.com/threads/how-to-drain-refill-automatic-transmission.63851/

 

1) Toyota Tacoma Automatic Transmission Temp Check Mode Tutorial-
2) Toyota Tacoma Transmission Fluid Change Drain/Refill Tutorial- I found these on youtube, copy these and paste on youtube. This guy talks you through the process and I found it very useful. Make sure it protains to your vehicle. After I properly filled my tranny with some Lucas Trans. Fix the Tacoma is shifting great. Not sure if it's because the fluid level is correct or the Lucas additive I installed. I say if your having shifting issues, use Lucas Trans. Fix and see what happens. It can't hurt, I installed two 24oz. bottles to bring my fluid level up in my trans. Thanks Jimmyh for the info.

 

I didn't read all the replies but it sounds to me like it's more than likely torque converter try to remember the check engine light only has to do with emissions something is messing with the air fuel ratio or exhaust or intake this is when you get a check engine light have anybody that may be having the similar issue if there's no check engine light more than likely it's in the transmission

 

No you've got to read past replies or your comment(s) end up somewhere in left field. There is both a check engine and check trans. light, when those come on your plug in your handheld code reader to determine what the code or problems is. No light(s) are lit, so you swap stories with others to see what remedies or repairs they did to solve the problem(s) that you're experiencing. It appears that Toyota manufactures do not want owners touching this delicate trans. for various reasons which as an old school mechanic I think is a load of crap. This is what happens when you have some genius who decided to reinvent the transmission. But it is what it is, so I had to learned how to properly service this tranny with the generous help from the guys and gals on here. It might seem a pain in the ass, and it is for simply wanting to do preventive maintenance and save money, but the video's I found are quite easy to understand and perform. Toyota you made'em but I'm gonna do my best to fix'em and keep dealers and high-priced shops from taking my money. Here's a tip, the next time you pay to have all the fluids check, on your Tacoma, ask how they checked the tranny and axle. Like my Tacoma there is no dipstick for the tranny, so all the mechanic does is look for any leaks and that's it?

 

*facepalm*