"Modernising" the 77

[77shortybawx]

Hey everyone. I have a chance at a couple c-10's in a junkyard 2 standard 80-87 models and 3 73-79 models, ones even a "Bonanza" Basically what i want to accomplish is put power windows, locks, overdrive transmission, cruise control, and intermediate wipers in my old truck. I am aware that the 700r4 transmissions have been known to have problems but this truck is my daily driver and the th350 is hard to on gas so if I can get the transmission cheap enough i'm gonna grab it. What am I gonna need to get with the transmission? are there any special computers that I should get with it? my question on the cruise control and intermediate wipers is there a single computer to control both or am I gonna need to grab others and will I be able to use my current wiper motor? I am fairly knowledgeable on electrics and have plenty of free time to do this project so that wont be an issue. I just need to know what to get and where it is generally located. And last but not least is it possible to put power locks and windows from a 80-87 model into a 77 without extensive modification? I already have the 80-87 style door panels on my truck now and I like the twist of the older body style with the newer features. Sorry if I confused anyone, its been a tiring day and I will try to explain What I am trying to do the best I can if needed. Thanks in advance. Alex.

[77shortybawx]

Terribly sorry about the double post but I forgot to add I will also post a build thread on this if it works out

[silvereagle07]

WIth the transmission you will need the crossmember, TV cable and intake throttle bracket. On the wipers system, you will need the motor and possibly the entire column (wiring is different). I'm not sure on the speed control.

[mhicks]

I just moved my crossmember back on my '73. Drilled some holes in the frame and bolted it back down.

[JohnC]

If you stay with the trucks before 85 you won't have any computers in them. with silvereagle regarding the tranny, and the wipers.

[mhicks]

I got this off of the board several years ago. Some of the parts needed for the tranny swap.

Which one to get?
The 700R4 was produced from 1982 until 1992. It was renamed the 4L60 for 1993, and I believe it's otherwise identical. 1994 brought the 4L60E, which requires a computer to run. The good years to get are any made in 1987 or later. Try to find a unit that has a mechanical speedometer as well, but if not, it's not a big deal to change one over. The 1987 and later units have quite a few improvements that do a lot for helping the 700's longevity.

If you're getting a rebuilt one, it's no different than any other kind of transmission - get it from a reputable shop. Ideally, the original core would be an '87 or later, but an older one with updated internals should work just as well.

Other Things Needed For Swap:
*Transmission cooler
*Cooler lines if there wasn't an auto in previously, or if the old ones are in bad shape
*TV (throttle valve) cable and a bracket to mount it - go to a dealer for these. P/N 25515598 Throttle valve cable @ $20.00 and Bracket P/N 22504927 @ $17.00 (GM) . Bracket has openings for accelerator cable and for the T.V. cable and bolts to back two bolts on Quadrajet.
*Speedometer cable - the one from my THM400 was just a few inches too short. Yours may work, but don't be surprised if it doesn't, the 700R4 is a long tranny.
*Automatic crossmember, shifter, and linkage if there wasn't an auto in previously
*New or modified driveshaft (chances are it will need to be cut and put a new yoke on it)
*Grade 8 hardware to bolt the crossmember in
*Metric bolts to attatch the torque converter to the flexplate - at least mine uses them, but given that the Chevy parts counter gave me SAE the first two times, my guess is not all 700's use them.
*Speedometer drive and driven gears, and possibly the sleeve, depending on the transmission and gearing/tire setup. There are two sleeves, depending on the size of the driven gear. Get the sleeve at a junkyard if you can; I didn't have the option of waiting and had to pay almost $60 for it over the GM parts counter!
*Patience

Tips for the swap:
For the most part, the 700R4 is a fairly straightforward install. There's nothing really special about the physical installation of the transmission; just drop the old one, put the new one in, bolt it all up, and drill holes for / bolt the crossmember in. Don't forget to mount the transmission cooler too! Call your driveshaft shop, measure the distance they want, and have yours modified to fit. (Now's a great time to go with a one-piece!)

The "tricky" parts, though, are the TV linkage and the TCC (torque converter clutch, aka lockup) wiring. I'm not even going to try to explain the TV linkage; this site does a GREAT job of explaining the details of it. It's also quite possible to "get it close" by just retracting the cable (it makes sense once you look at a cable, the end 'ratchets') and then moving the throttle hard to WOT (engine off, of course!), and then take it immediately to a transmission shop to have it adjusted. I set mine using the method in the page and it's working perfectly.


I have another good write up about the transmission itself if you want it. Give me your email address and I can send it to you.

[77shortybawx]

well everyone i scored a tilt column with all the needed switches, a complete wiring harness so i can upgrade from glass fuses to the spade type, a rear sliding window, (mine shattered yesterday) a gauge cluster, a wiper motor, 2 window motors, 2 power locks, 2 door panels that are not rotten, and an Edelbrock intake for a 350 for a grand total of... $30 i am going to practice everything on the passenger side door to make sure i am doing everything right before i take pictures so i am not giving anyone bad info. There is a 700r4 tranny down there yet. its on my list to get sometime soon.