Code P0770 - Shift Solenoid E Malfunction

Well, after a week of the truck in the driveway I think I have finally solved this damn code. My CEL came on while driving normally, code P0770, about 10 days ago. I had no issues with the truck and how it was shifting or anything related to the transmission. My beast ran just as fine as it always has. However, being the anal bastard I am, and knowing I'd have to fix my CEL eventually being that I live in CA and have to get it smogged every two years so I tackled the issue while the rain was absent.

For anyone tackling this job, read through the entire thing before trying to do anything. I'm not the king of how-to fix-it jobs, and Im definitely not the king of writing about them. Oh, and also I provided some pics and relevant images/manuals at the end. Forgive me in advance for any grammatical errors, I am starving and too tired to proofread this thing.

There were very few resources online regarding this code so confronting the issue was a bit of a challenge for me. I'd say I'm pretty adept at fixing most things on my truck, of course, I'd also add that I say and do so because I'm a cheapo who doesn't wanna pay anyone to fix something I typically feel I can do based off a 10 mn youtube video and a garage full of 40 yrs worth of collected tools - thanks pops. Anywho, onto the details:

Going into this project I knew there were three main culprits that could of been causing the issue:

- the shift solenoid had gone bad, that is the TCC Solenoid AKA the SL Solenoid AKA Solenoid E(I know why can't it just have one name @Toyota)

- the valve body was blocked up

- the lock-up clutch wasn't locking(this occurs at speeds of about 50mph and up and works with the torque converter to do so)

So first thing was first, I checked out my ATF levels and color to make sure it wasn't super low or burnt - a couple of things others on this forum noted could cause the issue. Fluid looked and smelled fine, not perfect, but I was content with it knowing I hadn't serviced the transmission in almost 40k miles and wasn't sure of the transmission service records prior to purchasing the truck. Onto the next thing to look at.



***NOTE: BEFORE MESSING WITH ANY ELECTRICAL STUFF, SOLENOIDS INCLUDED, UNHOOK THE BATTERY***

Secondly, I figured it had to be my shift solenoid, or at least I hoped it to be as it was the simplest things to replace, just sorta a PITA to do. So I got under the truck and started ratcheting. The pan is held on by 19 10mm bolts and a sealant material that works SUPER well. Slowly ratcheted the bolts off to be sure not to break one, then spent the next day trying to pry off the pan. Looking back at it, I think it could of come off much more easily if I had opted to stick a paint scraper in it sooner than I did. I banged on the pan with a rubber mallet, then stuck a paint scraper in between the pan and tranny. If you are to do this, be sure to try and position the scraper down towards the pan so if you happen to damage anything, you're damaging a replaceable pan and not the actual surface of the transmission. BOOM, I heard the gasket material separating and down came the pan. There was about 4 quarts of ATF in it to drain, plus the drippings that continued.

Next I inspected the debris in my pan, AKA the metal shavings, which are normal to have, but the amount in my pan was more than I'd like to see, and could indicate other issues, but like I have said, my truck ran FINE. Nothing out of the ordinary, the CEL just popped on out of nowhere.


I then inspected the solenoids, which is easy to do, they each have a bolt that connects it to the transmission, a plug where a wire harness plugs in, and an o-ring type thingy that plugs into the transmission in a little slot. I took each one out individually and tested it. This is done, firstly and most easily by connecting a HOT wire to the terminal of the solenoid, then to the positive on your battery. Then take a GROUND wire and connect it to bare metal on the solenoid, and tap it on the battery. If it makes noise, its probably fine, if it doesn't, it's probably no good. However, to further this, you can take a multimeter and test the Ohms of the solenoids. Typically this should fall between 12 and 28. After my tests I concluded it was the TCC Solenoid AKA Solenoid SL AKA Solenoid E that was the issue. It made no noise when tested on my battery.


Now onto the parts ordered:

- 1 ROSTRA Solenoid, part #520452, I 100% agree that to replace this you should use the OEM part, but finding the exact part number for it was something I still was unable to do. I knew I could order the 3 solenoids Toyota has on their site, but I was unable to differentiate which one was which, oh and also the OEM one was like $300 compared to $50 on RockAuto.

- 6 Qts of Valvoline Dex III ATF, #798153

- 1 New Transmission Filter, part #35330-60030

- 1 Tube of FIPG Pan sealant, part #00295-01281, this is the OEM material used at the factory to put the pan onto the transmission. However, I did see on my research others use aftermarket pans that came with a regular gasket, but again I try to be as OEM as I can.

Other misc. things needed:

- Paint scraper
- Large funnel
- Gloves, lots of gloves
- Brake Cleaner
- Gasket Removal Stuff(idk what it was called)
- Wrenches and sockets ofc

After 8 days of awaiting parts(FedEx had some dilemma, shoulda been 3 days), I finally put it all back together. Starting with the OG pan, I scraped all the gasket material off, which was also a PITA and took a solid 2 hours. My recommendation is to get as much off as you can with a plastic scraper of some sort, then go back with a gasket remover material, or in my case some straight up gasoline, and scrape scrape scrape that stuff off, then wipe wipe wipe that stuff off, repeat. Once the surface is clean, and I mean CLEAN, you're good to move forward. Oh and don't forget to do the same on the transmission surface too, though I just used a scraper and no removal material as I didn't wanna contaminate anything.

I then went ahead and plugged my new solenoid in, inserted it into its nice and snug little spot, and put its bolt in. Then I installed my new filter, make sure when doing this you remember where each bolt went. There are two goldish looking bolts that go towards the front of the vehicle, and two other bolts that go on the passenger side. IMPORTANT: Those two bolts, being the non-goldish ones, need to go back where they originally were. One of them is slightly longer. I didn't notice this until installation, and it wasn't a big deal. Just take a light and look at the transmission holes and see which one has deeper threads.

Next, I went ahead and put a bead, about 1/8", of the sealant on the edge of my transmission pan, and smeared it evenly over the surface with a gloved finger. Make sure you are all ready to put it back on before applying the material as it starts to dry in about 15 minutes. I then took the pan and put it back into place, being careful not to get any of the sealant on the interior of the transmission. It's also important to note, at least for me, that the tranny dipstick detaches about 18 inches up from the pan, so make sure you line that sucker up right and pop it on. I put the 19 bolts back on, starting at each corner and sort of going in a star pattern to be sure I got even pressure. These bolts, as well as the bolts inside of the transmission(solenoid bolt, filter bolts) all call for some very weak torques, about between 5-7 ft lbs. So, being that I don't have any baby torque wrenches I just hand tightened with a small little ooga booga at the end to get em snug.

Then, and this is important, don't put any fluid back into the transmission for 16 hours, I opted to wait 20 just to be sure the gasket material dries. After that time was up though, poor that fluid in through the dipstick hole. The amount can very, and I would recommend making a note of the amount of fluid that came out initially - I didn't which was a consequence down the road. It's argued that between 3.5 and 4 quarts are needed, but in my case it took 6 WHOLE QUARTS of ATF to get it back up to level. The reason being I believe, is that I dropped the pan about 3 or 4 different times and had my truck sitting for about 10 days, resulting in more fluid being lost than if this was all just done in one day. Each time I took the pan back off there was a pool of fluid sitting in it, plus all the drippings, I think that eventually added up to the 6 quarts that I needed.

Knowing how to read your ATF fluid level is vital. There is a HOT and a COLD measure on the stick. You should really only use the HOT level, which you look at after warming the car up by driving 15-20 minutes or about 5-10 miles. However, in my case I couldn't just drive it around to see the level as I had drained it, so I filled er up til the cold level was met. This is challenging to see because when the truck is off as you are just filling the fluid up via the dipstick, it is hard to read where the fluid is at on the stick as there is fluid that has run all the way down it. Anyway, once at the required level I turned the truck on and slowly shifted from P to R to D, etc. all the way to L, then repeated it a few times. Then I drove her around town for about 15 minutes, came home, checked my fluid, and GAAAAAAWLEEEE there was practically no fluid showing on my stick. Fast forward a couple more drives and it took 6 whole qts of ATF to refill to the right level for me. Hit my mark, then drove her around town again for about 20 minutes. No light came back on, and the truck shifted real nice(again, as it always has). *Small update about 3 hours after project completion. Looks like I do still need a bit more ATF fluid, so will be grabbing a couple more quarts to get her right.

Anyway, that's my write-up of this project. Sorry its not as eloquent as others can be, I just finished finals and have been writing way too much. Feel free to ask questions, but don't expect good answers, I'm just a dude who watches youtube videos when shit breaks and asks this forum.

PHOTOS and Manual stuff:

Here are a couple of relevant links to some sources I looked at:
shift solenoid E | Toyota Tundra Forum

 

This is a good read. Shift solenoid E CEL has been on for at least 5 years on my dad's truck. Its always ran and drove fine so we just left it

 

Precisely this. My truck ran perfectly fine when the light came on, and I probably drove it 60-80 miles with the light on. No issues, nothing. But like I said, I needed it fixed to smog it, and being that it's my primary vehicle, I'd rather there not be a CEL.

 

Great write up! $300 for an OEM solenoid??? Wow, good to know.

@shifty` you should reference this in your mega thread. There aren’t too many write ups on pulling the tranny apart to get at the solenoids.

 

Yeah I need to find a way to integrate this and @The Black Mamba’s thread together.

 

Really awesome write up. Wish I would've had this when I went through my solenoid issues years ago!

 

Nice work! And you did better than you believe on detailing the job.