I bought a good used transmission for my 96 LX450 and ask my local Lexus dealer what transmission fluid I needed to get. They checked it out and said I should put Type T-IV in it. Which we did. Now I ask my Toyota dealership when I was there for something else, just to double check them, and they said I should have put Dextron III in the LX450. I am confused. Welcome feedback about what I should do moving forward. Transmission probably has 500 to 1,000 miles with the T-IV. Did I mess up?
LX450 Transmission Fluid??
- Thread starter mwi555
- Start date
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NeverFinis
SILVER Star
My 1996 LX450 manual shows Dexron II.
With that said, newer Dexrons should be backwards compatible with earlier types, at least with GM transmissions. There are exceptions.
I found a Toyota Service Bulletin: TC003-99, which shows transmissions requiring Dexron II/III should only use Dexron II/III and not Type T.
With that said, newer Dexrons should be backwards compatible with earlier types, at least with GM transmissions. There are exceptions.
I found a Toyota Service Bulletin: TC003-99, which shows transmissions requiring Dexron II/III should only use Dexron II/III and not Type T.
COS80
SILVER Star
I'm running Maxlife synthetic in mine (in everything, actually). It's like a transmission tuneup in a bottle.
Dex III
Valvoline maxlife atf, easy to find almost anywhere.
Plain old cheap DexIII. Drain and fill once a year an it'll be fine. No need for fancy super synthetic or anything. T-IV is NOT the proper fluid for an old A343 trans.
Valvoline MaxLife, that's the short/cheap/excellent solution. IMHO.
- Thread starter
- #8
I appreciate the info. I’m afraid I’m in a pickle. I assume I need to have the transmission removed and all the fluid drained? Since just draining it would leave some in it and I understand from the service bulletin you can mix T-IV and Dextron?
COS80
SILVER Star
Correct, but there's got to be a way to fully flush out what's in there without removing the transmission.
Yes, do the Rodney Flush.
I posted pics of me doing it about three weeks ago.
Now I need to look at the spec of what I put in to determine if it's the correct type.
I thought that was one of your threads.
@mwi555 :
Agree all, no need to remove your transmission to remove the fluid. As mentioned above you want a complete Fluid Exchange also known as a "Rodney Flush" which basically is putting new ATF fluid in while pumping old fluid out from a disconnected Transmission cooler system hose.
The mixing that occurs during the complete fluid exchange (Rodney Flush) will not cause any damage, one suggestion is to use a few quarts more than the total capacity of the system so something like 16+ Quarts,
There are some mechanic shops that can do that for you but you have to ask the right questions ie: what type of flush (or fluid exchange) machine do they use,
how often they change the filter or screen of the machine, how much fluid do they use, etc, etc. IMO connecting the flush machine to the transmission cooler lines works well so ask if their machine can do that. AFAIK some shops now only use a machine that sucks ATF out of the pan via the dipstick tube then puts new fluid in via the same hose, so it seems like more like multiple drain and fills and not a complete fluid exchange.
Here's one video on how to do a Rodney Flush yourself. Start watching at 8:00 minutes for the Fluid Flush/Exchange section of the video (the first 8 minutes he dropped the pan and cleaned the filter which you don't have to do).
Agree all, no need to remove your transmission to remove the fluid. As mentioned above you want a complete Fluid Exchange also known as a "Rodney Flush" which basically is putting new ATF fluid in while pumping old fluid out from a disconnected Transmission cooler system hose.
The mixing that occurs during the complete fluid exchange (Rodney Flush) will not cause any damage, one suggestion is to use a few quarts more than the total capacity of the system so something like 16+ Quarts,
There are some mechanic shops that can do that for you but you have to ask the right questions ie: what type of flush (or fluid exchange) machine do they use,
how often they change the filter or screen of the machine, how much fluid do they use, etc, etc. IMO connecting the flush machine to the transmission cooler lines works well so ask if their machine can do that. AFAIK some shops now only use a machine that sucks ATF out of the pan via the dipstick tube then puts new fluid in via the same hose, so it seems like more like multiple drain and fills and not a complete fluid exchange.
Here's one video on how to do a Rodney Flush yourself. Start watching at 8:00 minutes for the Fluid Flush/Exchange section of the video (the first 8 minutes he dropped the pan and cleaned the filter which you don't have to do).
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Malleus
Far west of Siegen
@mwi555
I have searched (but not researched) and can't find a definitive answer on exactly what makes Type T (II, II or IV) different from Dexron III, in terms of what the impact on specific transmission components may be.
There are three types of components in an automatic transmission, at least the A343F, that could be affected by the oil, or additives in it:
» the metal components, which are aluminum or steel (and not likely to be affected regardless of which oil is used);
» the friction components (the clutch disks)
» the rubber O-rings and plastic seals
The friction components are stamped sheets which have friction material bonded to them. The bonding process uses very high heat (and pressure) to sinter the powder onto the sheet, and is unlikely to be affected by the oil or additives in it, per se. What happens during use, due to the viscosity or temperature limits of the oil is the consideration to keep in mind.
The rubber O-rings and plastic seals are really the heart of the transmission. When they fail, fluid goes where it shouldn't, when it shouldn't, and performance during operation suffers. Eventually, the clutch material will become degraded, lose its bond with the sheets and become dispersed in the fluid, due to splippage, and that is the eventual cause of (most) transmission failure.
My best guess about mixing fluids:
» In the short term, having Type T fluid in an A343F won't damage the transmission, in storage only.
» Mixing the fluids may result in lower than optimal performance characteristics, but probably won't degrade the internal components, due to chemical interactions. By that I mean that if you're towing heavy loads or hard off road wheeling you may see a difference; I doubt you would in DD on-road use.
» Continued use of Type T-IV instead of Type II/III: who knows, but I doubt it'll end the world. (If I had a spare overhaul kit lying around, I'd be willing to set up a rebuilt A343F with Type T-IV, just to see what the result was after a couple of thousand miles - I doubt it'd be a significant problem, but that's just my very unscientific guess).
Performing a total fluid flush, using the transmission pump and draining the fluid using the front cooler lines will probably suffice to get enough of the old "wrong" fluid out, and restore your peace of mind, if you're concerned about it. FWIW, dropping the oil in the pan is a waste of time and money. You can change your engine oil that way, but it won't work for the transmission.
Also, FWIW, here's a little set of musings from Toyota-Club.net on ATF. In a nutshell, it says "there are a lot of Toyota approved ATF oils and I don't know what the difference really is".
I have searched (but not researched) and can't find a definitive answer on exactly what makes Type T (II, II or IV) different from Dexron III, in terms of what the impact on specific transmission components may be.
There are three types of components in an automatic transmission, at least the A343F, that could be affected by the oil, or additives in it:
» the metal components, which are aluminum or steel (and not likely to be affected regardless of which oil is used);
» the friction components (the clutch disks)
» the rubber O-rings and plastic seals
The friction components are stamped sheets which have friction material bonded to them. The bonding process uses very high heat (and pressure) to sinter the powder onto the sheet, and is unlikely to be affected by the oil or additives in it, per se. What happens during use, due to the viscosity or temperature limits of the oil is the consideration to keep in mind.
The rubber O-rings and plastic seals are really the heart of the transmission. When they fail, fluid goes where it shouldn't, when it shouldn't, and performance during operation suffers. Eventually, the clutch material will become degraded, lose its bond with the sheets and become dispersed in the fluid, due to splippage, and that is the eventual cause of (most) transmission failure.
My best guess about mixing fluids:
» In the short term, having Type T fluid in an A343F won't damage the transmission, in storage only.
» Mixing the fluids may result in lower than optimal performance characteristics, but probably won't degrade the internal components, due to chemical interactions. By that I mean that if you're towing heavy loads or hard off road wheeling you may see a difference; I doubt you would in DD on-road use.
» Continued use of Type T-IV instead of Type II/III: who knows, but I doubt it'll end the world. (If I had a spare overhaul kit lying around, I'd be willing to set up a rebuilt A343F with Type T-IV, just to see what the result was after a couple of thousand miles - I doubt it'd be a significant problem, but that's just my very unscientific guess).
Performing a total fluid flush, using the transmission pump and draining the fluid using the front cooler lines will probably suffice to get enough of the old "wrong" fluid out, and restore your peace of mind, if you're concerned about it. FWIW, dropping the oil in the pan is a waste of time and money. You can change your engine oil that way, but it won't work for the transmission.
Also, FWIW, here's a little set of musings from Toyota-Club.net on ATF. In a nutshell, it says "there are a lot of Toyota approved ATF oils and I don't know what the difference really is".
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NeverFinis
SILVER Star
In my earlier post where I wrote there were exceptions; one exception was that Allison transmissions pre-2006 were not compatible with newer Dexrons due to seals.
From the web:
I suspect it is the same with the A343F. The seals used at the time of manufacturer are not compatible with newer ATF.
From the web:
I suspect it is the same with the A343F. The seals used at the time of manufacturer are not compatible with newer ATF.
Hell for over 15 years I’ve switched all of my Toyotas that are older (Non-WS fluid) to Dexron 6. It’s backwards compatible and fully synthetic with higher temp capabilities. It’s easy to source in bulk and relatively cheap. Also that fluid will be easy to source for many decades to come. Zero issues in all vehicles as the fluid is compatible, plus some now have smoother shifts. Well over 100k on multiple vehicles with zero transmission concerns or failures.
(repeating myself if the OP is still here) I'm running Mobil 1 Full Synthetic ATF in a 96 FZJ80 and Valvoline MaxLife Synthetic ATF in a 97 FZJ80 (both with the A343F ATM). Both 80's shift very well, only difference is the 80 with the Maxlife ATF has a slightly softer shift and both fluids are backwards compatible with the DEXRON II/III standards.
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Mobile1 Delvac1 hands down if you can swing the coins
The reality is that if you get any quality compatible fluid, you'll be good to go. Change it in a reasonable frequency and you'll be doing more than most.
I prefer synthetic from Eneos because it's from Japan, and my NAPA stocks it.
My transmission probably doesn't care
Malleus
Far west of Siegen
I use Mobil1 because it's the cheapest I can buy...it hasn't failed me yet.
