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That’s awesome great job, very well write up explaining how you went through with the process! It’s great getting your son involved as well, it’s good for kids these days to experience working on cars even if they are simply assisting their pops out.
You saved yourself hundreds of dollars if not thousands if the solenoid replacement fixed the problem.
I had to order an OEM S3 solenoid that’s coming from Japan, including brand new SLT and SLU solenoids for good measure. This entire issue has cost me more money than I expected and really has soured my purchase of my 05 LS 430 because I expected nothing really to be wrong with it, but again I don’t know how well the previous owner maintained the car. This doesn’t include a smog test which I can’t get done until I replace the solenoids and pray that the code goes away completely.
You saved yourself hundreds of dollars if not thousands if the solenoid replacement fixed the problem.
I had to order an OEM S3 solenoid that’s coming from Japan, including brand new SLT and SLU solenoids for good measure. This entire issue has cost me more money than I expected and really has soured my purchase of my 05 LS 430 because I expected nothing really to be wrong with it, but again I don’t know how well the previous owner maintained the car. This doesn’t include a smog test which I can’t get done until I replace the solenoids and pray that the code goes away completely.
Original quote for a remanufactured transmission was $6600. Total cost of everything between parts, fluid, and equipment was $272. I'm very pleased by that haha.
Don't worry - the LS430 is bulletproof! I'm sure that after your solenoids are replaced you've got a great chance of it serving you for years to come. This is my second LS430, my first one was an 04 that I had for about 5 years. It was generally problem free, though I did have an electrical issue that was beyond my skill level to address, and I ended up having to take it to a shop to have it repaired. I wanted to get a second one because these cars are an absolute vibe and they last for so long!
I have been on here a lot trying to solve my issues. I took my 2004 LS430 UL with 200,000 miles into a mechanic and had them replace the solenoid. Long story short, I didn’t like how they handled things and don’t feel they did a good job. They wound up putting in a non Lexus solenoid even though I supplied them with the solenoid I wanted installed. They didn’t follow the procedure for replacing the transmission fluid at proper temperature and I had to go about doing it myself. They refunded my payment after some back and forth. Anyways, I still have P2757. It triggers the hard code after two vehicle on/off cycles when speed reaches above 50mph (I believe the P2757 has to do with the 5th gear solenoids). No noticeable shift issues. I am considering sending in the ECU for a repair. However, I still feel unsure about what that mechanic even did to my transmission while he was in there. Not sure if I should just break down and drop the pan myself and install this Lexus solenoid that I have and see if that fixes things? Any thoughts?
Based on what I've learned, I believe the Torque Convert Lockup Control Solenoid (which will trigger code P2757) is what controls the torque converter lock-up function. In my limited understanding, lockup occurs when the transmission is in 6th gear while the vehicle is at speed, and is intended to provide better fuel economy, locking the torque converter mechanically at the interface between the engine and the transmission, rather than relying on the motion of the fluid. This produces a gear ratio close(r) to 1:1 between the engine and the transmission. If somebody else knows more, please chime in!
I found this video helpful to understand what lockup is:
One of the symptoms I was having with my car was that at highway speed, if I happened to let off the gas, the engine RPMs would drop to idle. This leads me to believe that lockup was not occurring when the ECU would send a signal to the lockup control solenoid. You may be experiencing that issue and just not realize, or it may be occurring intermittently as the solenoid functions intermittently on its way to the great scrap heap in the sky.
Nice job, way to get the little guy involved. He'll be changing your timing belt before you know it..👍
One thing to add, in the interest of future readers, is ALWAYS remove the fill plug on the side before draining fluid from the pan.
If you don't have the right tool to get it out after draining fluid you're dead in the water.
You obviously noticed how tight it is with no access for a ratchet/socket. Also, the 24mm* wrench is not commonly found in just any tool box.
A wrench is basically the only way to get it out. The fill plug has a rather thin head so I wedge a thin piece of wood next to the wrench holding it in place as I turn the fill bolt out.
-* a 15/16" wrench also works as there's only .007" difference.
@bradland would you be kind enough to clarify: When checking the trans fluid level at the proper temp of 115-130 degrees F using the D shift indicator:
a. While checking the fill level with the overflow tube, should the engine be running after removing the overflow plug, or should the engine be shut off when checking this level?Answered my own question on this, instructions indicate to check fluid level with engine idling.
b. should the fill plug be open or closed?
I've got an oil change coming up shortly and I'm going to check the transmission fluid level while I am under the car, and I just want to make sure I'm doing it correctly.
11622250[/url]]@bradland would you be kind enough to clarify: When checking the trans fluid level at the proper temp of 115-130 degrees F using the D shift indicator:
a. While checking the fill level with the overflow tube, should the engine be running after removing the overflow plug, or should the engine be shut off when checking this level?Answered my own question on this, instructions indicate to check fluid level with engine idling.
b. should the fill plug be open or closed?
I've got an oil change coming up shortly and I'm going to check the transmission fluid level while I am under the car, and I just want to make sure I'm doing it correctly.
Thanks!
a. Yes, running 👍
b. Also, Yes closed. Otherwise fluid will splatter out through the fill hole.
Helpful tip- you obviously want the car level when doing the final check. I’ve found it makes life easier to drop the car back down off whatever means you’re using to lift it.
Lift the car to drain the pan and replace fluid as necessary. Replace the fill plug and crack the test plug so it’s just snug. Once you’re ready to bring the trans up to temp drop the car back down. The test plug is within arms reach when the car is flat on the ground The test plug is already kinda loose so you don’t have to muscle it 👍
When replacing fluid add approx .25 to .33 Qt extra so you only have to go through this one time.
Alright guys, I did the job with mixed results. I replaced the SLU, SLT and S3 solenoids.
First off, I knew something was amiss when the previous owner took the car to a transmission shop and they stated that they replaced ECM, the strainer, and added 5 quarts of fresh fluid.
I call BS because the fluid was dark red and smelled old but wasn’t black, plus it was over filled, 4 quarts was drained but. You can definitely tell that the fluid wasn’t replaced if ever. The strainer looked original as well, plus I didn’t see any remnants of previous work being done, like removal of the drain pan bolts or exhaust bolts being removed. And supposedly the trans shop did all this back in September of this year.
There were a lot of metal shavings on the magnets, again, I could tell the pan was not cleaned at all therefore the shop lied about doing the job. Stay away from ghetto shops please.
After replacing the solenoids, strainer, gasket, and adding about 2.5 quarts of ATF, I didn’t have time to actually do the whole drain n refill procedure since I just didn’t have time and my body was sore as heck from laying under the car for hours, so I simply added the amount of ATF everyone recommended, I will do the proper drain n refill this weekend to make sure the level is perfect.
I was so excited because once I did the job, I took the car out for a drive and the transmission shifted perfectly fine. Every shift was smooth as liquid butter, but just last night I went for a drive, and the damn check engine comes on giving me the same P7061 “Shift Solenoid C Performance or Stuck Off” code.
The transmission went back into fail safe mode and the transmission would not upshift to gear.
I am completely at a loss, I spend about $500 for everything, mentally preparing to do the job and then actually doing it, hoping this was going to fix the problem.
Whats really strange is that the day when I decided to work on the car, when I started it up, the check engine light was actually turned off, weird. Then when I start the car and the CEL is on, it stays on and never just randomly turns off.
Could something be wrong with the ECM that was replaced? I mean how could the car run so good with me replacing the solenoids, adding some fresh fluid, run fine for 2 days, then all of sudden the CEL and same code pops back up? I would think if something was truly wrong with the transmission, wouldn’t the CEL come on instantly every time I start the car, and it not shift smooth at all?
Also what I notice was before the CEL came on, the ABS light was flashing and red triangle 🔺 on the dash lit up. Including the VSC light on the dash.
Does anyone recommend me to try something else to see if I can fix this transmission issue before I decide to take it into a shop for additional diagnosis?
I didn’t disconnect the battery to truly reset the computer, I will try that next to see if it will solve the problem, because maybe the previous code is still in the systems memory and still active. I did however clear the code from my scan tool.
Hi @FlexnLexus Geez that sucks the fix didn't work, I was really hoping it would for you. I'm gonna do some research right now and get back to you with some suggestions.
-Justin
Hi @FlexnLexus Geez that sucks the fix didn't work, I was really hoping it would for you. I'm gonna do some research right now and get back to you with some suggestions.
-Justin
Thanks Justin, yeah it does. I just did 2 more drain n refill's on the transmission last night. The pan took 3 quarts of fluid each time, and with this last D&R the fluid looked a lot better and I can finally see fresh fluid being drained out.
The transmission shifts even better now. What I found odd, is prior to doing the D&R last night, I had the car parked and running for awhile, I even drove it around a bit to heat up the fluid, and there were no codes present on my scan tool, nothing pending either.
Well after I was done with the job, I took the car out for a spin, and no problems, no CEL, but when I plugged in the scan tool, I got the same pending code.
I am thinking something electrical is wrong. Either the wire to the solenoid is bad or the connector is, possibly the ECU as well that was replaced. Because again, If the transmission needs a rebuild, the transmission would not shift at all, or have severe shifting problems constantly and not go into a certain gear each time the car is driven. I’m not experiencing that issue, but once the CEL does comes on, the transmission goes into fail-safe mode and won’t upshift passed 3rd gear.
But it doesn’t do this every time I drive the car. So strange, it does suck big time because I really like this car as it runs and drives great, and I can’t afford a new transmission as they cost a small fortune on these cars. I’m stuck in a rock and a hard place and might have to sell it for a loss if does need one. 😞
Hey @FlexnLexus , The drain and fills were a good call and will only help. I strongly believe that if the car shifts like butter sometimes, and then randomly pops a code and doesn't shift right anymore, that there's nothing physically wrong with the transmission and it does not need a rebuild; it's more likely something electrical. If there was something physically wrong that required a rebuild, why would the transmission shift perfectly smooth a lot of the of the time? That's just my intuition and I could be wrong, but I had this thought with my own trans issues and I ended up being correct, mine would shift perfectly a lot of the time but would randomly stop shifting right along with a CEL code coming up just like yours. More research is required for sure if there's an electrical issue somewhere causing the issue, but I do believe your trans does not have a physical issue. Hopefully some others can add to this and give their two cents, didn't get to do much research but I will soon and get back to you with any ideas I come across.
Hey @FlexnLexus , The drain and fills were a good call and will only help. I strongly believe that if the car shifts like butter sometimes, and then randomly pops a code and doesn't shift right anymore, that there's nothing physically wrong with the transmission and it does not need a rebuild; it's more likely something electrical. If there was something physically wrong that required a rebuild, why would the transmission shift perfectly smooth a lot of the of the time? That's just my intuition and I could be wrong, but I had this thought with my own trans issues and I ended up being correct, mine would shift perfectly a lot of the time but would randomly stop shifting right along with a CEL code coming up just like yours. More research is required for sure if there's an electrical issue somewhere causing the issue, but I do believe your trans does not have a physical issue. Hopefully some others can add to this and give their two cents, didn't get to do much research but I will soon and get back to you with any ideas I come across.
Definitely, I agree Justin. I took the car out for drive last night, and the transmission shifted absolutely perfectly fine in all gear ranges. The CEL didn’t come on at all the entire time I drove it either. I think maybe the more I drive the car, getting the clean fluid circulating throughout the entire transmission valve body, and torque converter, maybe that will help clear things up and get the transmission used to the new fluid, and solenoids.
Hopefully the transmission will work itself out, but the additional D&R’s definitely made the bigger difference. I might do another D&R in a couple of weeks or so since I want as much as the old fluid out of the transmission as possible because of how bad the old fluid looked before. I’ll update everyone if things improve further and if the problem is finally fixed.
Hello all, I'm providing and update after completing the job on my LS430 a week ago. I was able to drop my transmission pan and replaced two solenoids; SLU and SLT (lock up control and line pressure control solenoids). To do this I had to drain the oil out of the pan (drained about 3 quarts), and dropped the transmission pan. I took out the problematic solenoids and replaced them with solenoids I got from a junkyard LS430 for $18 each, and thoroughly cleaned them using sensor cleaner. The gasket around my transmission pan was totally dry and almost felt like plastic and I had to chip it off using a scraper. I cleaned the pan as well as the magnets in the pan, which had collected some metal shavings (this is somewhat expected after twenty years, nothing too alarming). I also cleaned the transmission pan filter as well (not much of a filter, more of a strainer) and reinstalled it. I also observed that my transmission pan had some weeping/leaking on the pan itself and around where the gasket was. I'll attach some pictures so you all can see this. Also the ATF that I drained was completely black compared to how it should look (bright red), which again is expected after twenty years. I then reinstalled the transmission pan after installing new solenoids, applied a brand new transmission pan gasket from Lexus. Then I siphoned in roughly 3 quarts of new ATF into the refill plug located on the side of the transmission (labelled 'WS' on the bolt). I turned on car and let it heat up to about 115-130F, which I monitored by using techstream running in a virtualbox on my macbook hooked up to OBD2 port under steering wheel. Once it reached 115-130, I loosened the overflow plug on the transmission pan (located near the drain plug, H5 hex tool needed to unscrew) and I let it drain out of there until it came to a slow trickle. All of this is proper Lexus/Toyota sealed transmission procedure to ensure proper fluid level, and it wasn't too hard to do myself. I also replaced washers (drain plug, overflow plug). Since, this job, I've driven about 300 miles in the past week, and I have great news. No more jerky shifting at all and I haven't had any codes show up. So far I can say all my problems are gone and I can even say that the car shifts smoother/better with about 30% new fluid. I may try to do a couple more drain/fills over the next few months and couple hundred miles driven in between. I hope this update helps some people in the future who come across this post with similar issues, and thanks to all who replied to my thread and gave their advice. I'll give another small update in a few weeks, or if anything changes. Thanks guys.
-Justin diagram with two solenoids I replaced circled in red old fluid (almost black) three magnets in the pan to collect metal shavings transmission solenoid circuitry old solenoids siphoning in brand new Toyota WS fluid
Hi Justin,
Thanks for your post! I am having the same issue. I recently bought this car and it has 188k and it seems like fluid has never been replaced. I got code P2757 and car seems to bounce when coasting to a stop or accelerating through the first couple of gears. It also stalled on me. I decided to do just a drain and fill with out dropping pan. Fluid was pitch black. It however Didn't work. Now I dropped the pan and fluid is still black. I took out both solenoid slt and slu and tested them. Ohm Resistance was in normal range and and they seem to be clicking. When you took the solenoids out did you test them or just replaced them?
I bought a used transmission from someone and will take out just these 2 and replace even though the original ones seem to be working fine. Hope it works.
@Smw Hey there! When I took the solenoids out, I did not test them (probably should have, to confirm solenoids actually fixed the problem not just the drain and fill), I just replaced them with SLU and SLT I took from a junkyard LS430. It's been a while but I think I saw a forum post about similar issue with a 6-speed GS and replacing those solenoids fixed their problem, I just figured I should try and it actually worked. That bounce when accelerating/stopping through first few gears sounds exactly like what I had; it feels so weird and bad for the car . I still have the solenoids and could actually test them, I may do that soon. I guess I haven't updated this post in a while. The bounciness is totally gone, and the car shifts like butter almost always; I would still like to do another drain/fill. The only 2 issues I have, only happen once in a blue moon, are 1) gear will slip and car won't go past 3rd gear, this really only happens once or twice a month if that, and issue is completely gone if I turn off the car and restart it 2) occasionally if I have to stop quickly (very rare with my driving style) there will be a transmission thud I can feel when I come to a stop, like a very late hard downshift. Both of these again only happen rarely, but it's still slightly concerning. My car feels perfect 99% of the time but in the back of my mind there is a little stress that my transmission may be on borrowed time; I guess it's time to get on that next drain/fill! Let me know if you have any other questions, and your results, I'm interested in hearing.. good luck!
@Smw Hey there! When I took the solenoids out, I did not test them (probably should have, to confirm solenoids actually fixed the problem not just the drain and fill), I just replaced them with SLU and SLT I took from a junkyard LS430. It's been a while but I think I saw a forum post about similar issue with a 6-speed GS and replacing those solenoids fixed their problem, I just figured I should try and it actually worked. That bounce when accelerating/stopping through first few gears sounds exactly like what I had; it feels so weird and bad for the car . I still have the solenoids and could actually test them, I may do that soon. I guess I haven't updated this post in a while. The bounciness is totally gone, and the car shifts like butter almost always; I would still like to do another drain/fill. The only 2 issues I have, only happen once in a blue moon, are 1) gear will slip and car won't go past 3rd gear, this really only happens once or twice a month if that, and issue is completely gone if I turn off the car and restart it 2) occasionally if I have to stop quickly (very rare with my driving style) there will be a transmission thud I can feel when I come to a stop, like a very late hard downshift. Both of these again only happen rarely, but it's still slightly concerning. My car feels perfect 99% of the time but in the back of my mind there is a little stress that my transmission may be on borrowed time; I guess it's time to get on that next drain/fill! Let me know if you have any other questions, and your results, I'm interested in hearing.. good luck!
***UPDATE** 5/29/24
Hi Justin, After borrowing the 2 solenoids from another transmission, I dropped the pan and installed new filter. Took about 5 quarts. Drove the car for about 30 minutes in normal and highway driving. Code didn't return, it usually returns relatively quick once the car drives over 50 mph, since that's when slu solenoid should start working. Car isn't bouncing and no more stalling. I'm also not sure what fixed it, the solenoids or the drain. I suspect the drain fixed it, since the replacement solenoids worked similar to the old ones. I believe just doing the drain without dropping the pan was my mistake, it just didn't remove enough old fluid and old fluid just didn't provide enough pressure for the transmission to function well, in addition to getting hotter than newer fluid. I will keep driving it just to confirm everything is hopefully normal. 😀
Hello all, I recently acquired a 2005 LS 430 and was having a very similar transmission issue. I found in the service records that previous owner took the car to the Lexus dealer where they were quoted $6500 for a replacement transmission, and then they promptly dumped the car. I am very happy to report that thanks to @ls430546 super detailed post and successful repair, I went ahead and ordered a new SLU and SLT solenoid and threw them in along with fresh fluid/filter and the issue appears to have gone away. I am thrilled that I was able to save this car thanks to all of the useful information on this thread! My symptoms were very similar and the repair seems to have worked like a charm, I hope I can help out any others who may come across this thread in the future.