Transmission can reverse but not drive forward

I have a 2007 toyota tacoma prerunner 4.0 v6 automatic i have reverse but no drive i put the code reader on it and I accidentally erased the codes I changed the filter and the fluid and I still don't have forward gears I have reverse what could it be and I have no way to find out what codes it could be unless someone can tell me how to get codes back on because I can't drive it

 

When you changed the fluid, how did it look? Black? Any metal? Can you roll it forward and backward when its in neutral? I had similar thing happen on my bronco, turned out it was my rear differential, some teeth had sheered off and the way they jammed in it was only allowing rotation in one direction.

 

Yes I can push it forward in gear and everything it don't make no noises all it does is rev up if you like milk it it like it tries to catch into gear but it had a transmission code and accidentally hit erase on the code reader and now I can't figure out what it is

 

Did you replace what was drained in terms of volume? Check the fluid level at the proper temps? Proper type of fluid? "WS" is the type you need.

There are a couple threads talking about how to put the truck in temp check mode. I use a scan tool personally, looking at both the tranny and the torque converter temps. When they are both in range is when I check the level. The truck has to be running while checking the level.

Did you mess with the neutral safety switch by any chance? It is on the passenger side of the transmission opposite where the shift cable connects. If your shifter ever feels sticky or hard to move, soak that down with some WD-40. Especially the side facing the transmission.

Good luck

 

That is drained all the fluid and put a new filter in it and then filled it all back up until it came out fill plug Crank It Up and I had reverse but no Drive still but whenever I put the code checker on it it had a transmission code and I forgot to write it down and I accidentally hit erase so I don't know what code what's popping up and now I can't check the codes on my truck to find out what code it was is there anyway I can get the code to come up since I can't drive it

 

You need to get it up to the proper temperature before you fill it. It is probably still low. search for the fill procedure here.

 

It sounds like you are still low on ATF.

Read this how-to:
https://www.tacomaworld.com/threads/how-to-drain-refill-automatic-transmission.63851/

 

The temp needs to be 97-115 on older models. How many miles on the truck? Could be a torque converter issue.

 

It has 375000 on it and its a 2007 4.0 v6 automatic i filled it up when it was cold and then i cranked it up and got it warm and then checked it again and i had to add som but its got 4 1/2 quarts of transmission fluid in it

 

Nope, converter works the same in all gears.

Guessing you probably have a clutch/brake issue or a solenoid problem. I'm no expert on the Taco 5 speed but low fluid level usually takes out reverse because it has one of the highest loads on the pump.

Do you get anything if you manually place it a lower gear? That would typically eliminate a solenoid problem.

Time to run the flowchart. If this occurs only when the code appears most likely an electronic issue. Assuming you have the fluid level right

 

Just to be clear, the entire system holds 12-13 quarts of ATF...

How do you figure it has one of the higher loads? Reverse is a fairly low ratio right?

 

Lower gears require higher fluid pressure because they have the highest torque multiplication. Reverse is usually the gear that calls for the highest fluid pressure.

Does it do anything different from D range to manual low?

I will say that the Taco has one of the biggest pain in the ass ways of setting fluid level without a scan tool.

Having said that, I've been working on shit for 21 years, have a Master ASE certification, Toyota T-Ten certified, and I taught Toyota courses for 5 years. I did my trans service in the fall and my synopsis was "this sucks balls".

 

Classic low transmission fluid issue

 

I jacked the ass end of my truck up and have both wheels off the ground and put it in drive and it goes it changes gears and everything but as soon as I put the wheels on the ground my truck goes nowhere

 

The level check port will drain fluid if it's not running. At temp, it any drains, let it until it's a trickle.
That said. You should have drained about 3 quarts. Put 4 in. That includes what you put in already. When you changed the filter, more came pouring out.

Get a scan tool and the torque or obd fusion app. You want to make a gauge for the transmission and torque converter temps each. When they're both in the correct range, remove the check port and let anything drain to a trickle. Do this while it's running and in park.

Edit: wait a sec. Did you actually fill it up until it was coming out the fill port? Am I reading your quote correctly?

 

I'm hoping that was a typo on the OP's part.

 

Hard to tell with no punctuation haha

 

Oh no

 

So it'd be overfilled by a quart or 12