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74 Chevy Truck Want To Install 700r4

07-23-2004, 12:45 PM
Hi! I Just Got This 74 Chevy Truck With A 350 2bbl It Has A Turbo 350 Transmission On It And I Wanted To Know Of I Could Install A 700r4 Of A 87 Chevy Truck With The 6.2 Litre Diesel. I Got The 87 For Parts,i Want To Know If Would Be A Problem If I Currently Don Have A Lock Up Switch On This Current One.if Any Body Is Intrested In The 6.2 Diesel Just E-mail Me.(was Running),another Thing If I Can Change The Tranny Would It Improve My Fuel Economy And Performance I Am Currently Getting Around 10 To 14 Mpg Depends How I Drive.
Thanks Ray.

07-23-2004, 04:42 PM
It will probably improve the fuel ecomony, ya know with the overdrive it couldn't hurt :) You do or don't have a lock up on your trans? If you run the 700r4 without you will risk burning it up.

10-18-2004, 01:34 PM
It will probably improve the fuel ecomony, ya know with the overdrive it couldn't hurt :) You do or don't have a lock up on your trans? If you run the 700r4 without you will risk burning it up.

I should be getting my truck finally ready with the 700 r4 transmission on it and i will get back with the MPG.

10-20-2004, 08:01 AM
They make a kit for the Lockup for a 700R4 for older vechiles without the computer. Seen them in Summitt and Northern. around $ 100 worth it to keep from burning the Trans up.

10-20-2004, 11:59 PM
Im not sure but I think you can get the lock up kit cheaper at

10-21-2004, 01:38 PM
Thanks for the info and jegs is cheaper

10-21-2004, 02:23 PM
I ran my 1992 c1500 x-cab 5.7 with the converter lock up disconected for 30,000 miles due to a faulty converter after the converter was replaced the trans was still good for at least 60,000 miles and was still good when I sold the truck

10-21-2004, 05:33 PM
you still run the chance of burning it up.... it is there for a reason.

11-11-2004, 10:04 AM
Well the transmission has been installed and the transmission guy got the lock up to work. He added a power wire from the fuse block to the lock up.
He said that this would work since the lock-up only work in OD. Does this sound right. I have since ordered the lock up kit and waiting for it to come in.

I am a little dissapointed that the performance seamed to have dropped. When I go from 60 to 80 it seems to take much longer that before. So I might just go back to the 350 and have it rebuilt. Also it does not smoke the tires on take off like it use to. It feels wimpy.
Please advise.

11-11-2004, 10:20 AM
yeah, that sounds like a 700r4 to me. Are you accelerating hard enough to activate the detent cable and kick it down a gear?

11-11-2004, 10:25 AM
It will smoke the tires but then it will up shift to second pretty quick unless i leave it in first. The detent cable seems to be adjusted properly because I thought that was the problem. But when I got to checking it seems to be on with no slack and it feels hard to pull on it should I take it back to the guy that put the transmission on.

Yes I have the pedal to the metal when I take off and for it to down shift when I want to go pass someone sometimes it will down shift. When it does it only jumps out of overdrive and not to second gear.

11-11-2004, 12:39 PM
I have done this 700 r4 swap in my 69 Chevy. My input would be getting the b&m lock-up controller.
You can adjust the speed that the converter locks up at and you can by-pass that only in 4th gear crap justIncase you want to tow something. My experience with the 700r4 is that it will help with wear & tear on your motorbeing able to cruze at low rpm. But the first gear is steep and it shifts out quick. Second is long. This makes the 350 seem like it is faster b/c first & second gear seem equal under hard acceleration. If you want to see the benefit of the 700r4 put some 340 gears in the rear end. The steep first gear will rap up you motor quick and the over drive will have you cruzing 80mph at 2000rpm.

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