1980 Gmc Transmission swap

[iaminsman]

I have never done a swap before, but I purchased a new th350 to swap the old th350.  I purchased a service manual and want to try this myself.  How long does a swap take, and are there any special tools needed?  How difficult is this to do for a newbie??  Any advice would be apprecitated.  If it is too difficult, I will just take it to a shop and spend the $$$ although I don't want to.  Thanks....

[Firebird_TA]

I am hoping that you are working on a two wheel drive truck here, because it is a lot easier.  First, set the parking break and put a log behind each rear wheel.  Then, jack the fron of the truck up so that an 18" tall part will clear everything(enough room for you and the tranny to get out easily.  Next, remove the speedometer cable from the back of the trans(channel locks help).  Then, using a 1/2 or 9/16" wrench(line wrench if you have one), loosen and remove the transmission cooler lines from the side of the trans.(watch out, fluid will leak out a lot)  Then, loosen the transmission mount bolt(s) and support the trans with a floor jack and a 2x4 under the pan(don't want to crush the pan and risk another leak).  Then, go to the front of the trans and remove the dust shield, followed by turning the engine over(by hand preferrably) and removing the tree torque converter bolts(2 nine sixteenth wrenches).  Then, remove the crossmember that is under the back of the transmission by the tail cone.  These are out of order, sorry.  Remove the driveshaft from the back of the trans by loosening the carrier bearing and dropping it from the frame.  Remove the shaft from the rearend also and go ahead and install new u-joints all around.  Now the trans is almost ready to come out.  Next, up by the carb, there is a kickdown cable, remove it and pull it down to the trans with you.  Then disconnect the vaccuum line on the side of the trans.  Then remove the shift linkage from the transmission.  Now, with the jack still under the trans and you as far away from the trans as possible, remove the starter and the six bolts holding the trans to the back of the block.  Then pull the trans back and allow it to slowly drop using the jack and a friend.  Then pull it out from under the truck, shake hands with buddy, go clean up, order pizza or chicken and some kind of cold beverage and come back in an hour or two and do all of this in reverse to get the new trans in.  Then drive it easy for a while until the trans breaks in, about 500 miles ought to do.  Then, playtime.

[red4wd]

Just a thought here but you might want to wait until the end to remove the cooler lines

[Lt.Del]

It really is simple if your arne't new to turning bolts. Just remember how you take the old out.  I like to use my digital camera and take pics of everything...linkage, lines, etc..That way you can use your laptop, once you tranfer pics there, as reference when putting the new one in.

The hardest part, aside from lining up the tranny to the engine, to start a few bolts to pull the tranny in, is getting the top two bolts of tranny to the top of the engine.  The side bolts can be done with a long extension on your ratchet and a swivel, but the top ones, man, you best take your time and just use a box wrench. Dont bust your knuckels