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DetroitDan · 12-10-2010, 01:59 AM

I'm interested in this too, I have a 454 with a th400 and I would seriously consider swapping to a 700r4 if I could be convinced it would be strong enough. I've always heard bad things about the 700s, but I've also heard it was due to people towing in OD, and other heat related lockup issues. My 83 owners manual actually recommended driving and towing in OD all the time. Maybe that's why by 1985 all the 700s were blown and they had a bad rep. I like the idea of wiring it into the brakelight circuit for automatic on and off, but honestly I wouldn't mind having to switch it either. Anything to try to improve the fuel economy at this point.
I had a 66 Impala with a 2004r in it with a toggle switch operated OD, seemed simple enough, basically just provided 12v to the trans plug iirc.
Will a 700 bolt up to a 205 case? I'm already leery about losing the strength of the th400, if I have to give up the 205 and change to a 208 I don't think I'd even bother. I'm pretty hard on drivelines, that's why I have 1 tons for daily drivers in the first place. I know the 4l80s are stronger, but I think they require a computer to run the electronic OD.

12-10-2010, 01:59 AM	#9
DetroitDan Registered User Join Date: Dec 2009 Location: Epping, NH Posts: 605	Re: 700r4 lock up question I'm interested in this too, I have a 454 with a th400 and I would seriously consider swapping to a 700r4 if I could be convinced it would be strong enough. I've always heard bad things about the 700s, but I've also heard it was due to people towing in OD, and other heat related lockup issues. My 83 owners manual actually recommended driving and towing in OD all the time. Maybe that's why by 1985 all the 700s were blown and they had a bad rep. I like the idea of wiring it into the brakelight circuit for automatic on and off, but honestly I wouldn't mind having to switch it either. Anything to try to improve the fuel economy at this point. I had a 66 Impala with a 2004r in it with a toggle switch operated OD, seemed simple enough, basically just provided 12v to the trans plug iirc. Will a 700 bolt up to a 205 case? I'm already leery about losing the strength of the th400, if I have to give up the 205 and change to a 208 I don't think I'd even bother. I'm pretty hard on drivelines, that's why I have 1 tons for daily drivers in the first place. I know the 4l80s are stronger, but I think they require a computer to run the electronic OD.