Transmission Flush - ECT ECU Reset - Road Test
#1
Intermediate
Thread Starter
Transmission Flush - ECT ECU Reset - Road Test
So I performed a transmission fluid flush/replacement yesterday in my 300k mile 2014 AWD 460. Needless to say it needed to be done (gray fluid smelling off) was very messy but I got it done. I have access to techstream and reset the ECT ECU (it said for when replacing the valvebody assy) I didn't see one for "new fluid". Either way it said to "perform road test in accordance with manual". What does the "road test" consist of here? I just drove it around normally, shifting gears in the S mode, as well as leaving it in automatic, did a couple of more aggressive starts. It hesitated sometimes, hung gears at the beginning, and didn't want to get into 6-7-8 for the first 10 min. But after continuing to drive it it kind of all fixed itself. But I have a residual worry that I screwed something up. I did pull the drain plug at 95-109C IAW instructions and can confirm the fluid level is correct.
Anyone know what the "road test" is after an ECT ECU reset?
Anyone know what the "road test" is after an ECT ECU reset?
#2
I do. It's in the FSM.
#3
Intermediate
Thread Starter
#4
Out of shop, day off. Will do as soon as. But main gist of 'Road Test' is to gently accelerate from 0 to 50mph, letting tranny go thru all gears, then decel to 0. Should be done on a straight road and within some time limit.
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dan25man (03-12-23)
#5
Umm, did you say you set level at 95-109c? Is that temp centigrade? If yes - that is incorrect, you have an underfill. Tons of recent threads on how to check trans is at proper level set temp. I think it was 60C or something.
#6
Lexus Champion
95 degrees is in F not C, road test is the second you start the car go drive it up to around 50-70 through all gears and then slowly stop. I also like to do at least two 0-130 runs at full power
Do that a few times for it to learn its shift offsets, if you really did fill at 95 Celsius then you royally under-filled it....
Do that a few times for it to learn its shift offsets, if you really did fill at 95 Celsius then you royally under-filled it....
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Boykie (03-12-23)
#7
Lead Lap
iTrader: (1)
100c is boiling point of water, 212F. Unless the cooling system is overheating, that temp is not possible. If my logic is incorrect, please correct me as to why.
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#8
Trans fluid isn't water and also it's under pressure, so boiling point is higher anyways. But let's wait for OPs confirmation.
#9
Lexus Champion
#10
Lead Lap
iTrader: (1)
Excellent points. I forgot that trans fluid, while cooled, isn't cooled by the coolant in radiator (which is typically no hotter than 185F). It's cooled by air flow and could certainly get hotter than 185F.
#11
Intermediate
Thread Starter
All, wow, thanks for the comments guy. I was just following the procedures written up in this thread by @kuWuPt :
https://www.clublexus.com/forums/ls-...ion-flush.html
So yes I had an OBD reader connected and displaying the transmission temperature. It took about 20-25 min idle to get that temperature. At ~97 C I removed the overfill plug and let the excess fluid come out. So maybe it's underfilled?
https://www.clublexus.com/forums/ls-...ion-flush.html
So yes I had an OBD reader connected and displaying the transmission temperature. It took about 20-25 min idle to get that temperature. At ~97 C I removed the overfill plug and let the excess fluid come out. So maybe it's underfilled?
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THE_CEO (03-12-23)
#12
97 Celsius centigrade????? Yes! It's underfilled!
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swfla (03-12-23)
#13
Something needs to be done about that thread!! Mods? It's dangerously misleading. I expect up to a quart under.
#14
Lexus Champion
Jesus Christ that's hot. Wow.
#15
Advanced
iTrader: (13)
Temperature is supposed to be in Fahrenheit and not Celsius. Over 108 degrees Fahrenheit would definitely cause the transmission fluid to expand more and drain more than needed. If you top up the food all should be good. The lower oil level would result in lower pressure which is what is causing the transmission to not shift into the higher gears. Really sorry about that, I'll correct the thread..