Mark W
Yep, it's true. I just don't care that much.
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Has anyone here encountered an A343F shuddering from low or burnt fluid? (1 Viewer)
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Yes
and any transmission will start to shudder, burn ATF and clutches, if ran on low atf for a considerable time!!
and any transmission will start to shudder, burn ATF and clutches, if ran on low atf for a considerable time!!
Mark W
Yep, it's true. I just don't care that much.
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My personal experience with the 440, 442 and 343 has always been that slipping and funky shifting have been the first symptoms I have encountered. Was just starting to diagnose a '97 last night that seems to have tranny shudder that comes and goes once the rig warms up but has no other symptoms. Gonna look closer at it this morning, but thinking it is a fluid issue. Just surprised that there seem to be no other (reported) symptoms.
Fortunately it was towed in as soon as it started acting up so if it is low/bad fluid he has likely not done any further damage.
Mark...
Fortunately it was towed in as soon as it started acting up so if it is low/bad fluid he has likely not done any further damage.
Mark...
Bit of scope creep with this contribution but I recently encountered the reverse howl/shudder/slip/grind in my '97 while reversing up hill. Fluid level was a touch over top mark at operating temp and this happened just after a few hours of highway driving. Haven't encountered this in forward gears or low range and haven't run the trans with low fluid. Fluid doesn't smell/appear burned from the dipstick.
Is there a list of known good ATF for the 343 anywhere? I've been changing a gallon per year via the pan drain and fill but am planning to drop the pan and inspect (plus increase pressure) and then do a full fluid flush and I'm curious what fluid to use. I've searched the forum a few times and have seen a few references but nothing like a consensus beyond Dexron 3 compatibility so maybe it doesn't matter too much?
Is there a list of known good ATF for the 343 anywhere? I've been changing a gallon per year via the pan drain and fill but am planning to drop the pan and inspect (plus increase pressure) and then do a full fluid flush and I'm curious what fluid to use. I've searched the forum a few times and have seen a few references but nothing like a consensus beyond Dexron 3 compatibility so maybe it doesn't matter too much?
This is a fairly common issue with the A343F. There are several threads regarding this, and it only seems to happen in reverse. I had it happen once to me in my 97LX450 and it made my stomach turn.
Yeah, I've likely read most of those threads and have learned a lot from them. The reverse issue also doesn't necessarily relate to issues stemming from "low or burnt fluid" but there could be overlap in some cases.
I mostly contributed here to learn more about general ATF opinions/experiences for the a343f since it seems like that does overlap a lot with the "low or burnt fluid" focus of this thread. I search/research first but haven't been able to nail down much conclusive evidence on ATFs to avoid or that have proven solid from the forum and have even seen conflicting evidence where something like Valvoline Max Life reportedly lead to issues in one case while it was great in another, etc. etc.
Edit: there's also good ATF info outside the forum like the following which indicates using Toyota T-TIV ATF could be a good option for the 80 trans:
Toyota ATF type T-IV vs Dexron III - DAVES OIL CHANGE
davesoilchange.com
FWIW, I've been using Amsoil ATF in both the A440F and A343F for the last 30 or so years. I do a passive drain/refill about every year or so, and the fluid is always bright red. Never had any issues with either transmission, with the exception of the reverse squeal on the 343 when backing up a steep incline in high range.Yeah, I've likely read most of those threads and have learned a lot from them. The reverse issue also doesn't necessarily relate to issues stemming from "low or burnt fluid" but there could be overlap in some cases.
I mostly contributed here to learn more about general ATF opinions/experiences for the a343f since it seems like that does overlap a lot with the "low or burnt fluid" focus of this thread. I search/research first but haven't been able to nail down much conclusive evidence on ATFs to avoid or that have proven solid from the forum and have even seen conflicting evidence where something like Valvoline Max Life reportedly lead to issues in one case while it was great in another, etc. etc.
Edit: there's also good ATF info outside the forum like the following which indicates using Toyota T-TIV ATF could be a good option for the 80 trans:
Toyota ATF type T-IV vs Dexron III - DAVES OIL CHANGE
At one point a few years back, I was planning on dropping the pan on the 343 to up the clamping force with the adjuster, but never got around to it.
To answer the OP's question, IME with low fluid I've gotten something between no shifting and slipping, but this was after one of my first drain and fills ever on an FZJ80 then driving a couple miles while maybe two quarts low. I stopped and filled the transmission correctly and no further issues, so no burning.
Slip/shudder in some A343F transmissions is a known issue, mostly in Reverse however, more common in the earlier models (pre late 97 models), there was a Toyota TSB or two on the issue. Search TSB Transmission.
Also, IME, the A343 is somewhat sensitive to the type of ATF used. Also additives can mess it up ie: don't add any, no matter what it says on the bottle to fix slip/shudder, they can make it worse.
I haven't had any problems with Mobil 1 synthetic ATF or Valvoline MaxLife Synthetic ATF. IME a quality flushing/cleaning chemical (LUBEGARD or AMSOIL Trans Flush for example) followed by a complete fluid exchange and then some (~14-16 qts) may help.
You could send a sample of the ATF off to Blackstone Laboratories for fluid analysis but I might not do that until you've done a complete fluid exchange (or send two samples, what is in there now and then after a fluid exchange to compare).
IME old fluid (like 25 year old original ATF) can be dark and have very high metal levels (PPM) even in a good transmission.
Slip/shudder in some A343F transmissions is a known issue, mostly in Reverse however, more common in the earlier models (pre late 97 models), there was a Toyota TSB or two on the issue. Search TSB Transmission.
Also, IME, the A343 is somewhat sensitive to the type of ATF used. Also additives can mess it up ie: don't add any, no matter what it says on the bottle to fix slip/shudder, they can make it worse.
I haven't had any problems with Mobil 1 synthetic ATF or Valvoline MaxLife Synthetic ATF. IME a quality flushing/cleaning chemical (LUBEGARD or AMSOIL Trans Flush for example) followed by a complete fluid exchange and then some (~14-16 qts) may help.
You could send a sample of the ATF off to Blackstone Laboratories for fluid analysis but I might not do that until you've done a complete fluid exchange (or send two samples, what is in there now and then after a fluid exchange to compare).
IME old fluid (like 25 year old original ATF) can be dark and have very high metal levels (PPM) even in a good transmission.
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Thanks for the specific brands here. Are there particular versions that you've stuck with as there are variants of all of these, unless I'm mistaken.
I use their standard ATF. Product code ATFQT (ATF in a quart size bottle). The gallon size is ATF1G, but I wouldn't use this cause I'd just make a mess.
FWIW, I use Amsoil products for everything.
If it says it's backwards compatible with Dexron II/III fluid it should be good. If any question you could call the manufacturer and ask if it doesn't say it on the bottle.
I'm sure the AMSOIL is good stuff, I just can't afford it
For a complete fluid exchange on the possible problem transmission you might consider the cheaper stuff first, you can always change it out later.
I did this to my 97 model, planned to use the Valvoline MaxLife Synthetic (from Wallys Mart) to clean out the old original fluid then change out to Mobil 1 synthetic afterwards, but it shifts so well with the Maxlife I left it in there. FWIW
I'm sure the AMSOIL is good stuff, I just can't afford it
For a complete fluid exchange on the possible problem transmission you might consider the cheaper stuff first, you can always change it out later.
I did this to my 97 model, planned to use the Valvoline MaxLife Synthetic (from Wallys Mart) to clean out the old original fluid then change out to Mobil 1 synthetic afterwards, but it shifts so well with the Maxlife I left it in there. FWIW
The a343 works really well with the toyota D2 ATF, dexron 3 is as good. Once its starts shuddering and doesn't get fixed by an ATF replacement - it needs to be repaired
