Some really bummed out news regarding my 05, so I called a very reputable local transmission shop that specializes in older Lexus vehicles, specifically the LS 430’s.

I spoke with the technician and explained to him what my problems were, and he straight up said, “I see it all the time, especially with these particular cars, replacing the solenoids depending on the code and problems your having, doesn’t always cure the problem, it’s always an internal issue with the clutches that are badly worn down and a transmission rebuild always fixes the code permanently”.

The low range cost for a rebuild depending on how bad things are internally will cost anywhere from $2,500 on the low end, and upwards of $4,500 on the higher end.

Or do you guys think I should look into buying a low mileage good used transmission online like EBay for like $1,200 and have it installed?

I honestly can’t afford to even fix the car at the moment as I’ve already spent a lot money getting solenoids, fluid, taking it to a shop for diagnosis, still need to smog it since the CEL won’t go off now.

I spent $7,000 on buying the car, so at the moment, cost is a concern for me, or else it’s going to have to sit until I can save up some more money to have it rebuilt.

My last ditch effort is to replace the valve body with a rebuilt one and have it installed to see if that will fix the issue, but again that’s more money I’m just throwing at the car which might not actually fix the problem completely.

 

If you can find a legit low mileage used unit that is the way to go. One example
https://www.ebay.com/itm/126152913322

Consider getting a 2nd opinion. Don't replace the valve body that very likely will not fix your issues.

 

Shipping will obviously be an issue so finding one locally is key.
Using https://car-part.com/ it looks like there are 3 in the SD area all at https://jdmwestside.com/

Half a dozen more a little over 100 miles away.

 

$300 shipping is reasonable. Yes local is better. I have bad luck with these parts engines 90% of the salvage yards either don't want to bother telling me anything, won't ship, act like they have no idea the part is even listed or other such nonsense.

 

Thanks for those links guys! I just called JDMWest and ask about the transmission, and they sold them already.

The car-parts.com is a cool site locating parts, I had no idea about them.

I saw another low mileage 04-06 LS 430 transmission on EBay for like $1,200 somewhere with free shipping.

I’ll shop around and see what’s the best deal and quality transmission I can find. But locally is definitely better, I can have it shipped to a trans shop and just pay for installation.

 

I had the car for a week at reputable trans shop locally, not the other one that specializes in Lexuses, but one close to my home, and the technician thinks it could be the valve body that is bad.

The other trans shop where the previous owner took it too, couldn’t figure out what the problem was either. So I’ve been trying to see what main culprit is for awhile now and don’t know what else to do besides replacing/rebuilding the trans like the one Lexus trans expert explained to me.

The car does have 157k miles on it, and some young girl (early 20’s) owned it for several years, that should have been an instant red flag preventing me from buying the car, but it’s in such good shape otherwise and these cars especially the 04-06 years are getting harder to find for good price that’s been well taken care of so I took the plunge.

 

I get that sometimes you have to fire the parts canon. But IMO if the valve body is shot (usually from poor fluid quality) the rest of the transmission is in the same condition or worse. I've been down the road (sorry bad pun) of having a transmission rebuilt it didn't last very long and never felt right. Once bitten twice shy.

It's nice that you found a shop specializing in Toyota/Lexus.

 

Makes sense, the transmission fluid did look pretty bad when I dropped the pan and replaced the solenoids, a lot of metal shavings on the magnets as well.

Thanks again👌

 

Replacement Trans is of course a risk... Might just have similar issues or different ones from an older Trans... Rebuilt trans offer different concerns.. Quality of the rebuilt, and what is not replaced.... Either one is a toss up.. As much as we love our cars.. replacing transmissions is usually time to replace the car... regardless of the repair... the rest of the car is old and other issues are on the horizon... NOTHING LASTS FOREVER!

 

I would spend the money to have the trans ECU sent to SIA electronics.
these transmissions are not known for failures until at least mid 200k miles at least.

 

I guess I can send it out to see if it will help.

Whats so strange is that today when I drove the car, the transmission was shifting perfectly fine after disconnecting the battery and ECU for a day.

Took it on the freeway, smooth shifts, no problems or CEL. After about 30 mins of driving, I get off the freeway sitting at a stoplight, I take off and suddenly the transmission gets stuck in 3rd or 4th gear. I put the gear selector in Sport mode, and I can manually control the shifts and it works fine. Put the gear selector back into Drive after using Sport mode and the transmission shifts fine again for a while. There’s no slipping, or noises or harsh shifting at all with the transmission. No hard downshifts, or problems downshifting.

So it’s very intermittent, and random, but disconnecting the battery for a while seems to cure the issue for a bit, vs just clearing the code from my scan tool.

 

Without a known good ECU you'll never eliminate it as a possible cause.

 

For the life of me i dont know why people are so hesitant to send out the ECU. For $150ish, get the ecu looked at. Also, verify with the dealer which ecu you should have. It is possible the ecu was swapped trying to fix it and sold on to you.

Take your VIN to the dealer and ask to order a bew ECU. They will verify the ECU part number. Compare that number to your ECU and look at the ecu for a repair sticker. Send out ecu if it is the correct part number for your vehicle.

Then consider the more expensive options. Or sell me the car cheap.

 

Definitely try the ECU first and then I would buy a used transmission, only if you can find reputable place for a rebuild that has done several rebuilds on these transmissions.

 

I’m gonna go out on a limb and say basically everything you’ve typed in this post points to the ECU.