2012 Transmission Kicks When Stopping Fast

Was the fluid low ? Did you change your sensor? I am not sure how my fluid was changed but same symptoms as you


Also my VSC light came on after my fluid change not sure how that is related
Gonna put a scanner on that this week

 

Dave , did you have the pan off when you changed your fluid ?

 

The fluid level was fine before and after I replaced it. I'm not sure what sensor you are talking about. Fluid level is set with an overflow port and transmission temp.

 

Two years ago, I acquired a 2009 Toyota Tacoma pickup truck; 4.0L V6, automatic, 4x4 with 116K miles. Shortly after purchase I noticed an intermittent problem when lifting my foot from the accelerator and coming to a stop. Within a couple of seconds after the stop, I would hear and feel a mechanical bang and shutter that felt and sounded like someone had hit the vehicle from behind. Secondly, if immediately upon coming to a complete stop I accelerated again without waiting a few seconds, the engine would rev up but the transmission not catch immediately and I would feel the bang as the transmission dropped into gear and the rear wheels would chirp as the transmission caught. The problem would also occur when slowing down to make a sharp turn, when re-accelerating after the turn the engine would rev a little and then drop into gear, a mechanical bang would occur then the transmission dropped into gear.

Took the truck into my local Toyota dealer twice with no success in curing the ill. For my third attempt, I took it to a second Toyota dealer in another city. Each time I would take a mechanic for ride to demonstrate the problem with me driving. Over the course of the following year, the dealerships did a transmission flush, tightened frame bolts, checked the differential, did a transmission firmware update, etc. etc., etc, charging me each time, not fixing the problem and never acknowledged problem even existed. Told me it was the way I drive, that it was a characteristic of that transmission, that it was because of the non-factory wheels and tires I have on my truck; again, etc. etc., etc. Once I was even told that the mechanic had another Tacoma on the lot similar to mine and he could duplicate the issue in that vehicle as well so it isn’t a problem. Basically telling me that’s the way the vehicle is designed is it is not a problem. Telling me that if there was a real transmission problem I would get a check engine light.

Last week I decided I would try one more time. This time I had the Toyota mechanic drive my truck with me as passenger and I instructed him in how to duplicate the problem. He reluctantly acknowledged the problem, did some digging and found a historical error code P0751 that pointed to a transmission shift solenoid (35240). This code did not appear when I scanned the codes with my ODBCII scanner. Unsure how he found it.

The service manager remained reluctant and indicated they would not guarantee this replacement would fix my problem and he recommended I not do it? I elected to remove all excuses so I went ahead with the repair. So, I had the dealer order and replace that transmission solenoid ($1,028 repair). This did in fact eliminate the problem. I’m back in love with my Tacoma. Given that many people reported experiencing this issue within a few weeks of purchasing their 2009 Tacomas new, can’t help but wonder if this wasn’t a faulty part that Toyota refused to recognized for financial and reputation reasons. My hope is by posting this I save someone else the aggravation of getting Toyota to admit there is a problem.

 

Considering I asked twice and he didnt answer , lets assume he left the pan on and just dropped the fluid . Not a big deal , but saves us from trying to diagnose his issue and eliminates possibilities

Why is it people come for help and then dont answer simple questions ?

What usually happens in both the above situations and more often when guys change their fluid " WITHOUT " removing the pan is blinding off the SLT solenoid .

Your transmission pan is the septic tank of the transmission .
Your old fluid worked well by carrying particles to the pan all its life but now the reagents in your old fluid are spent .
You introduce new transmission fluid with super derergents into the pan . The new fluid scrubs all those particles off the pan bottom , the pan magnets and the pan screen and forces the particles through your valve body and solenoids . This is very common and happens on a steady basis at Tacoma World because guys are not servicing their transmissions correctly .
Read the link below

How to properly service your transmission 101
https://www.tacomaworld.com/threads...e-2nd-gen-transmission-pan-and-filter.726329/



Now , when you are coasting to a stop , your SLT solenoid is commanded to close but the inner bore of the solenoid is all plugged up with those particles. The computer in your truck sees the problem and ramps up the pressure to compensate . This is very common
You can read more about the issue in depth to see if it sounds like your problem
http://bluegrasstoday.com/wp-content/uploads/2012/07/a750e_shudder.pdf

 

You actually had the engine running while the transmission fluid was draining?

 

I adjust the fluid level all the time with the engine running .
Nothing is going to happen if you cycle through the gears with the overflow bolt removed and the engine running .

Now if you are draining the fluid out the drain plug with the engine running and shifting the transmission through the gears at this time , you shouldnt be servicing your transmission, let a professional do it

 

You spent $1000+ to replace an electrical component on a 13 year old truck with well over 100,000 miles. To "FIX" a non-existent problem. It wasn't hurting a thing, just a slight annoyance. If spending that much you could have spent a little more and had the entire transmission rebuilt. With the other money you spent on transmission flushes and other repairs chasing the problem you literally have already spent what it would cost to just do a complete rebuild. If it were my truck I'd have driven it another 200,000 miles and lived with the "issue" and then paid to get the transmission rebuilt.

 

You seem very concerned with how dude spends his money. Reminds me of an upset SO lol. Why do you care?