I did a TH-400 install on my 97 firebird and now I am ready to try it out but the thing wont go in reverse, only forward gears. I tried adjusting the shifter cable but still nothing. It will physically go in reverse just nothing happens. Also something else odd is that the thing is leaking fluid out from around the converter. I put royal purple Max ATF fluid in it. Is that stuff too thin for a brand new transmission? Should I just drain that stuff out and put normal fluid in it?

Anybody faced these problems before with there TH-400 install??

Thnx

Clint

 

Do you have manual low or 3rd gear?

 

Vince is pointing in the right direction. The low/reverse band and the direct clutches have to be applied to get reverse.
I'll bet you've either got no manual low or 3rd gear to go along with the no reverse.
Was this a used transmission?

Frank
CPT

 

Humm Im not sure I checked to see if I have 3rd gear or not. I just checked first and second gear. It was a brand new transmission I bought from a guy on the board a year or so ago. It took me awhile to do the install as I am putting a 383 and 12 bolt along with it and it has taken me 2 1/2 years to actually get it to this point. But it was a brand new looking. Im not saying I was lied too of course. He supposedly had it custom built to handle 1200 HP. But I know some local shops around here that claim the same thing then 2 weeks later they break under a 300 hp car. About the Royal Purple any suggestions on that leak around the converter?

Thank you for your help

Clint

 

Oh on a side note wold fluid level effect reverse in anyway? I wouldnt think so but I am not expert. I have put about 5 qts in it but still isnt full according to the dipstick but I dont want to overfill it. I have the B&M deep pan and a B&M HD tranny cooler with -8AN lines.

 

Does this transmission have a transbrake?

 

First, get the fluid level correct and then go from there, otherwise its all speculation.......

 

No transbrake yet, I wanted to make sure the trans worked before I changed out the valvebody. I will change out this fluid and see what happens. I hope it is something simple as I have a dyno tune schedualed for next month at Futral Motorsports. I have to have this thing going by then.

 

I had one built a few years back, and had no reverse. a buddy of mine done it, and he just forgot something inside the tranny. it was a simple fix in my case. just my .02

 

Anything I can check?

 

Ok Changed the Royal purple out with Valvoline ATF fluid and still have the leak coming from around the converter, do these things need vent lines? Or something of that nature? I just cant see a new tranny with all new seals leaking fluid. While the car is on jack stands I checked to see if I have 3rd gear. The tires go forward in 1st, 2nd 3rd and even reverse.

Do I need to check the shifter cable again?
Is it possible that I have the wrong shifter/tranny combo IE I have a forward gated shifter and a reverse pattern valve body? I dont know if its even possible to crank that way just guessing.
I figured bolting this up would be easy!

 

Disconnect the shifter cable from the tranny and manually shift it, see if you get the gears then. Then you will know if you have thewrong cable/shifter or installed it wrong.

You only have 5 qts? Did you check the dipstick tube? My th400 took 10-12 qts once the converter was filled. I have a cooler and a deep pan.

 

Well I want to try that but I have open headers right now which is blowing exaust right there. So I might try to see what I can do anyway.

Thank you for the reply

 

Hey I checked to see if I have 3rd gear again and I dont. I started the car and put it in park and gave it gas nothing. bumped it once which should have been park 2 and the tires started moving forward with gas. Then Nuetral. Then went all the way to third gear and tried it and gave it gas and it did nothing bumped it up to second and they started moving again same with 1st. I tried calling around about this Alamo transmission place and one place said they heard of it but didnt know the number. I finally got the number to the place but it only was a non working number recording.

 

Park, Reverse, Neutral, then your forward moving gears. What is Park 2 ??

I would call any local tranny shop and have them look at it. It's just a TH400, pretty common tranmission.