Transmission slippage if stopped on incline

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Mar 7, 2020
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Oregon
Have 2009 LC with 200k miles, that recently, if I have to STOP on an incline….slides backwards while in “D”, as I remove my foot off the brake and move toward the gas pedal (the normal motion). The slide backward is so aggressive (gravity on a 6k pound truck and the traction error light comes on), I’ve had to use my left foot on the brake As I hover over the gas pedal with my right foot so that I don’t slide into a car behind me. ATF has recently been replaced although the fluid was black when drained (after only 20k miles after previous change). Diff fluids were changed about 20k miles agol. AB60F Transmission overall shifts as normal (no rough shifting)…no other complaints other than this safety issue of the “sliding back“. I’ve never had transmission issues at 200k!, just always changed the fluids so I know I’m due for some maintenance. And if anybody has a good transmission person in the Portland, Oregon area…shoot over any recommendations. Does anyone have any thoughts as to what might need fixed? (Trans clutches, thorough fluid flushes/exchanges, etc.). I appreciate anybody’s help, Thank you!
 

bloc

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When you say atf changed 20k ago, was it just a pan drain and fill or a full fluid exchange? Ie was it 4qts or 12?

Edit: saw your subsequent post about full exchange. Your new fluid should not be black after 20k. You may have slippage happening that is burning a clutch or clutches, and ruining fluid.
 

kcjaz

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OP, if on an incline, in drive, stopped with foot on break, will your truck just keep rolling backwards as you take your foot off the break or will it stop itself after a slight backwards roll? I ask because every all wheel drive Toyota I have owned as well as my Taco in 2WD, rolls backward slightly and the MTS or ATRAC kicks in and stops it. At first, I thought there was something wrong but they all do it. It takes a pretty good slope for this to happen but my driveway is steep and I have just grown accustomed to it.
 
Joined
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Messages
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Location
Oregon
When you say atf changed 20k ago, was it just a pan drain and fill or a full fluid exchange? Ie was it 4qts or 12?

Edit: saw your subsequent post about full exchange. Your new fluid should not be black after 20k. You may have slippage happening that is burning a clutch or clutches, and ruining fluid.
….it was just a pan drain…not a full fluid exchange…was the 12 quarts. My concern is what you mention….possible slippage happening that might be burning a clutch or clutches…..causing the fluid to blacken so relatively quickly. Being at 200k, I’ve replaced a number of parts so far (just recently)…and wanted to check the great minds in this forum if I might be looking for a problem (vs. a normal slip for a 6k pound vehicle). Thank you for the thoughts! Very appreciated.
 
Joined
Mar 7, 2020
Messages
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Location
Oregon
OP, if on an incline, in drive, stopped with foot on break, will your truck just keep rolling backwards as you take your foot off the break or will it stop itself after a slight backwards roll? I ask because every all wheel drive Toyota I have owned as well as my Taco in 2WD, rolls backward slightly and the MTS or ATRAC kicks in and stops it. At first, I thought there was something wrong but they all do it. It takes a pretty good slope for this to happen but my driveway is steep and I have just grown accustomed to it.
Gotcha….good point. I also noticed on my driveway (very steep like yours)…it happening. I’ll start by doing a full fluid exchange (and not just a pan drain)….and then see how the incline slippage might correct. Thank you!
 
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I have a great Toyota dealer (who knew?) near my house that is shockingly fair on price and so far, great on service…..so I’ll take her in this week to do a confirmation on the fluid level, and confirm The pan drain OR was it a full-exchange (I’ll get records as I’m questioning myself whether it was full exchange or pan drain) 20k miles ago to determine if indeed some friction might be occurring in the transmission (fluid black too soon). I’ll start with gathering that information….doing a full ATF exchange and then keep on top of the levels and go from there. I want to thank you all very much for your thoughts, means a lot.
 

bloc

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….it was just a pan drain…not a full fluid exchange…was the 12 quarts. My concern is what you mention….possible slippage happening that might be burning a clutch or clutches…..causing the fluid to blacken so relatively quickly. Being at 200k, I’ve replaced a number of parts so far (just recently)…and wanted to check the great minds in this forum if I might be looking for a problem (vs. a normal slip for a 6k pound vehicle). Thank you for the thoughts! Very appreciated.
Dark fluid after 200k and only changing one third of it wouldn’t surprise me. But if you did the full exchange of 12q, and it was dark after 20k, you have a problem.

So it sounds like you aren’t too far off normal.

There is a good write up around here on the exchange. I’d look that up.
 
Joined
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Oregon
Dark fluid after 200k and only changing one third of it wouldn’t surprise me. But if you did the full exchange of 12q, and it was dark after 20k, you have a problem.

So it sounds like you aren’t too far off normal.

There is a good write up around here on the exchange. I’d look that up.
Thank you Bloc very much!
 

WCDAVE

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Not sure if you've been doing much wading, but I had a breather come loose on a Jeep years ago and it made a mess of the fluid. It was MT so couldn't speak to the roll-back issue.
 

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