trans swap

[gafiredog]

i have a 83 c10 with a 250, and three speed. i want to put in a o/d trans. like a 4l60 ,etc. does this type of trans have a lock up converter? and doesn't it shift by a computer module of some sort ? what do i need to put it in my truck? thanks, Art

[piecesparts]

You could go to a 700 R4 tranny and hook that up, so that you don't have to purchase a computer link setup. The 700 R4 trannys evolved to the 4L60, then on to the 4L60E trannys over the years. Yes, the trannys do have a converter lockup feature and the 4L60 and later are computer controlled. I am running built up 700s in my trucks, one has a lockup converter and the other does not have the lockup feature---both ways CAN be done, but you have to decide on what you want to do when you build it. What will be needed to lock up the converter is a switch connected to the throttle or the trannys pressure lines to give a lockup signal when needed. There are numerous systems on the web or schematics available.

[COMP]

have seen T-5 swap's to

[LEEVON]

You probably want to use a 700r4. like piecesparts said, there are kits available for the lock-up. I found it to be simple enough to piece together for
free from the junkyard. The later 700's already have the internal provisions for lock up, it's just a matter of providing 12v power through a vacuum switch and brake swith for a factory-like install. Both of these can be had at almost any junkyard, easy to find in later blazer and 'burbs. The swap should be straightforward, maybe an x-member move and driveshaft modification depending on application.

[D13]

The biggest problem with the 700 swap will be the TV cable. GM never put it behind an L6 in the US (might have in Argentina). The TV cable is critical for 700 (controls line pressure like the old vacuum modulator on a TH350) and the geometry of the cable to the carb is critical for good driving and trans life.
Assuming its a 3 speed manual, you will need an auto column or a floor shift. Since it's an 83 you probably have a cable acellerator and a staged 2bbl carb and you can rig a way to drive the TV cable (look at TCI and Lokar for some ideas). I have not done this personally but I understand that the cable connection at the carb can be difficult to make and route. The calbe itself will probably have to be longer (custom) since your carb is further away from the trans. You will have to measure the trans and your existing shaft and eiter cut it or put in a shaft from an OD equipped truck, and possibly the trans support too. If you can find a junk yard donor 83-86 with the OD trans set up (very common) and get the xmember and shaft you'd be way ahead.

[gafiredog]

thanks for the info D 13

[gchemist]

Ditch the electrical wire up. Install an aftermarket stall converter. I used two and they work great.

[LEEVON]

Originally Posted by gchemist

Ditch the electrical wire up. Install an aftermarket stall converter. I used two and they work great.

He's probably going for increased gas mileage judging by the fact he's using a 250 I6. The lock-up will decrease highway rpm's and reduce tranny heat. Both will create better mileage and longer life.