# Transmission swap



## hyfye (Jul 15, 2013)

I have a 67 GTO with a built 68 400. I just blew up my 700R4 transmission and am trying to decide to put the turbo 400 back in or install a 4L80E. Has anyone done this conversion? I am kinda scared of the computer control.
Socrates


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## PontiacJim (Dec 29, 2012)

hyfye said:


> I have a 67 GTO with a built 68 400. I just blew up my 700R4 transmission and am trying to decide to put the turbo 400 back in or install a 4L80E. Has anyone done this conversion? I am kinda scared of the computer control.
> Socrates



Not a transmission guy, but from what I have read, the 700R4 is not a strong trans in stock form. Don't know if yours was stock or aftermarket.

The TH400 will be much cheaper, and certainly very strong, but will need a good rebuild with HD parts, and new converter. You will lose the great low first gear ratio of the 700R4 and the OD. I don't think I would want to give that up. 

Seeing you already have the 700R4 fitted into your ride, why not simply go with another trans built to handle the HP and torque? I personally don't care for things controlled by computers, but the electronic controlled transmissions can be used with a computer/wiring kit - which is another additional cost.

Check out this guy and all the info he has up about the 700R4 trans. I don't have one, don't know anyone with one, and am not endorsing this guy, but he seems to offer a heavy duty trans for your HP & torque levels that sounds like it will hold up with no problems. I am sure other companies offer a built trans, but I found this guy. The 4L80E may be an option, but I am just thinking that you have the 700R4 already fitted and you know how it works behind your engine. Going another route may mean more work or more $$.

Check it out. 700 Raptor 700r4 700r4 Transmission 700r4 700r4 700r4 PATC 700r4 700r4 700r4 700r4 700r4 700r4 700r4 700r4 700r4 700r4 700r4


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