Auto trans issue

Hi all,
First post here and I’ve been learning a ton from you all over the last year since purchasing my first Tacoma. I have a 01 Prerunner 3.4 with 131k. Yesterday I left home and immediately got on the highway. While accelerating and as I got to around 50mph the trans felt like it slipped out of gear. When I let it idle back down it went back into gear until it got back up in speed. I pulled over immediately and checked the fluids and leaks, but nothing. Fluid is clean and full and no leaks. I continued on the street not reaching more than 40mph and had no issues. I tried the hwy again after around 30 minutes and it was normal. I was able to get to 75mph with no problem. Today it happened again, within about 5 minutes of running. Seems like maybe it’s an issue until it warms up. Hoping it’s a common issue with a easy fix. Please say so, please!!! And thank you!

 

Welcome to tacomaworld! I'd be easy on your trans until you see the your coolant temp needle get above the "Cold" marking. The A340 transmissions tend to have a delayed 2-3 shift when cold. Not sure if that is your issue, but it could be related. If its not happening when its warm then it may well be. Typically if you start and go while cold, you might feel 1..... 2........................... (JERK) 3....

https://www.yotatech.com/forums/f116/a340-shifting-when-cold-99705/

https://www.tacomaworld.com/threads/automatic-transmission-shift-issues.716891/

If anyone can add to this that would be great. About all I got though.

 

Not common. That speed is about where it should hit overdrive. Since it takes both speed and correct temp to shift to OD, as previously mentioned its very common when trans/fluid are not up to temp for the shift to be delayed and engine run at higher RPM until temp is reached. This time of year, it should get to operating temp within 3-4 miles at that speed.

No idea if @gearcruncher still frequents this site, but I'm sure he'd have some good advice.

Otherwise, I'd definitely get the fluid and filter changed ASAP. Smell the fluid for "burnt" smell and see if it's closer to black than red. Two indications its past due for a change. Especially if the truck has often been used for towing.

 

Update… I drove streets only on my way to work accelerating slowly. I could feel the trans wanting to “slip” in between various gears and as soon as I let off the gas it would go back into gear. I checked my Scan Gage and there was no codes except I didn’t realize there was an option for pending codes. Sure enough code P1780 neutral safety switch. After some TW research, I had no idea that my turn signal that was being wacky(slow, regular and not working sometimes) was related. Looks like a bad ground from either my trailer light controller or reverse camera(newly installed last week) was the source of the issue. I removed my trailer lights and camera this morning and the pending code immediately triggered my check engine light. I cleared the code and drove it and everything is back to normal! Yay!!! I will need to replace my trailer connection anyways as the connection to the right turn was already ripped out of the connection box. I will also re- wire my reverse camera(not tied into the reverse bulb ground). Again, so grateful for your comments, thoughts and links!! TW folks are the best!!

 

Glad you fixed it! So a bad ground from an accessory was giving you a neutral safety switch code? Very interesting.

 

Yeah, I definitely thought it was a transmission problem. Been a couple days now and it’s still running great. Now on to that dash rattle…..

 

That's great!