Transmission or differential issues

Backstory...
A couple of weeks ago I got in the truck leaving work while it was pouring down rain. I backed out of the spot and put the truck in drive but nothing happened. I pressed the accelerator a little, then a little more and suddenly there was a massive pop that shook the truck and I jumped forward. I felt like there was a slight drag as I'm pulling out of the parking lot but by the time I got out of the parking lot, the truck drove just fine. Shifting and driving just as smooth as any other day. I chalked it up to rust being on the brakes from the rain and went home.

A couple of days later I started to head to work. Jumped in the truck, let off the parking brake, put it in drive, and nothing happens. I give it some gas and boom another big pop and I'm on the move again. A little drag as I'm driving but a block down the road and I'm back to driving like normal again. I decided to park the truck and take my other car until I had some time to do some testing because I thought maybe it was a brake that was getting stuck.

Today...
I back the truck out of the driveway and put it in drive, nothing. I just rock the gas peddle until the truck gives a tiny pop and I go. Pulled it into the garage and lifted it up testing each wheel and they all spun without any issues. With it up in the air, I started the truck and put it in drive, nothing... Turned the truck off with it in drive and spun the back wheels with no issue. The driveshaft was spinning, wheels were spinning, I couldn't hear any grinding or odd noises.
Put it back on the ground and backed it out of the garage and now it's having issues backing up. I drive forward to put it beside the house and it's really struggling to move forward with a lot of acceleration.

Now I'm at a loss as to what in the world is wrong with it. I did do the 20 minute drive to heat up the transmission fluid and when I parked it, the oil was way above the high mark where the dipstick has a twist in it whether it was hot or cold. I haven't changed the oil or put any oil in it so I'm not sure why it's so high.

I'm hoping for some guidance. Is the the transmission cooked? Is there something wrong with the diff? I tested and checked everything I could think to check but I'm not sure what else to check. Any help would be greatly appreciated!

Thanks!

 

Sounds like the rear brakes are doing things they aren’t supposed to do.
While I’m new to the Tacomas I’m certain I read a thread a while ago about the parking brake doing things like you’re describing.
Something about the lower linkage on the brake shoes acting up and not releasing properly

 

That's what I thought as well that the parking brake or rear brakes were not releasing but when I lifted the truck up in the air, the rear wheels spun without any issues at all. I rolled them forward and backwards with my hands and they spun super easy with no dragging spots making me think it's not the brakes. Still could be but right now I'm thinking it's worse just the way it was acting while driving.

And everything goes away after driving just a block or so that just makes it that much more confusing.

 

Did you try that before or after the clunk and release? Next time it act ups don’t force the truck to move, jack it up and try spinning the wheels first. That will tell you whether or not it’s the brakes sticking.

Ok, I read your initial post again. I would still pull the drums and check the brakes, you may have loose pieces inside the drum that binds when trying to move under power

 

It happens whenever the truck is cold and has been sitting for several hours. I pulled the truck in the garage early this morning and let it sit for a while before doing the test. I can try again tomorrow morning because it is on level ground and the parking brake is off.

I'm not very good with drum brakes but I can definitely pull both wheels and drums to see if there is anything out of the ordinary.

 

Make sure it's not coolant leaking into the trans fluid and vice versa (they share the radiator). Otherwise sounds like a solenoid issue

 

I’ll guess a broken rr parking brake cable.

 

OK update... The truck has been sitting on the side of my house and it's driving me crazy.

I called a couple of local shops and one said that it was the solenoids but if it wasn't then it would be a full rebuild. $350 (solenoids) to $3500-$3800 (transmission rebuild after he solenoids have been replaced).

Another shop said it was pressure lines inside the transmission and that they would just replace the transmission. I didn't ask how much that would cost...

Today I started it to make sure the battery didn't go bad. I put it in drive and nothing happened, no movement at all.

Let it run for about 10-15 minutes for the engine to get up to full temp. Put it in drive and the truck and it moved forward like there was no issue.

Now I really don't know what to do. Is it a full transmission rebuild or is there something that can be replaced and it cost less? Any guesses?

 

Im in the parking brake camp - mine did some similar things when the parking brake cable was freezing up. I woukd expect a transmission or diff issue to be more consistent.

 

Is there something I should be looking for if it is the parking brake? It looks all intact and when I lifted the rear of the truck up, there was no binding and both wheels spun without any issues.

 

I vote brakes.

Drums aren't hard, but they can be annoying for anyone and a bit confusing the first couple of times in.

Find a buddy comfortable working on drums and get them to look over your shoulder as you examine and service them