[60over68400]

anyone know how easy or difficult it is to put a 2004r in a firebird? Mine is a 68 with a 400. I'm pretty sure that bolting to the bellhousing isn't the problem. What about the crossmember? I have a TH-400 in there now. Do I need to modify/replace it? Some help would be greatly apprieciated thanks

[Donovan]

200 4r is the same length as a TH350

Transmission mount pad is the same as the TH400

Spline is the same as the TH350

There is a part of the trans pan that hits the crossmember but you will space it up just enough to clear. Or cut and mod (heat and hammer) etc... the crossmember. Be sure you use Metric bolt to bolt up the mount to the case.

Bellhousing is universal or multi-bell etc.

So you need the TH400 Crossmember and the TH350/ST300 driveshaft

I have heard that you just need to change out the TH400 slip yoke to a TH350 unit? Maybe.. Also, If you don't have the detent or kickdown cable adjusted correctly the trans will die in a mile of driving or less. So be sure to use the kickdown cable. Use a TH350 kickdown cable bracket for this.

[Karch]

Originally Posted by Donovan

200 4r is the same length as a TH350

Transmission mount pad is the same as the TH400

Spline is the same as the TH350

There is a part of the trans pan that hits the crossmember but you will space it up just enough to clear. Or cut and mod (heat and hammer) etc... the crossmember. Be sure you use Metric bolt to bolt up the mount to the case.

Bellhousing is universal or multi-bell etc.

So you need the TH400 Crossmember and the TH350/ST300 driveshaft

I have heard that you just need to change out the TH400 slip yoke to a TH350 unit? Maybe.. Also, If you don't have the detent or kickdown cable adjusted correctly the trans will die in a mile of driving or less. So be sure to use the kickdown cable. Use a TH350 kickdown cable bracket for this.

I was told you can use your old driveshaft but use a 700R4 yoke, it's longer to make up for the length.