350 turbo transmission problem. need help

[dbmx66]

ok so i have a 84 k10 350/350 4x4 setup.

dropped a freshly built 355 in. engine runs perfect.

first thing is when i tried to shift into drive i had to give engine a good amount of gas just to get it to go. it went in other gears fine. after we added soma fluid and let it warm up it was fine, kickdown needed some adjustment, ran down the driveway, then the hole truck started to clank and shake, brother sed its prolly the auto (junk)hubs trying to engage. but it only did at 5mph or so (drive and reverse). after the truck gets going its fine. so we took it around the block everything was fine, it shifted at 2200-2500 it was good. brought back up to the shop, shut it off cuz it was getting hot, (low in coolant) let her cool down added coolant, fired her back to take it to get inspection, wont go into reverse. and after you find reverse it takes a decent amount of gas to get it to even budge (like it did first time in drive). you can get to drive fine but it doesnt wanna go into reverse. and the actual column linkage is tight to shift.

checked trans fluid, it looks like a strawberry milkshake (moisture in trans). when it was idling in park after it was kinda clanking, but the engine is fresh with under 5k miles on it. (its def not a knock).

what do i do! even if there is moisture in the trans, that doesnt explain why it wont find reverse and go into drive fine, but yet an hour before it wouldnt go into drive but would go into reverse fine. it doesnt make sense, what should i do thank you

[csb#356]

You must have a problem with the transmission cooler leaking into the transmission or water got in there some other way. I would atleast change the fluid and filter and see what happens. But i'd investigate that leak for sure. I think water in your transmission fluid would cause all sorts of problems for shifting

[James McClure]

THM350 holds 13 QT's of fluid. converter has to be drained out for a full fluid change. Also, is there the posibility the motor got to hot and it poped a head or intake gasket? If the eng is ok, replace the radiator. First, fix linkage. No matter trans good or bad, linkage has to be right. Next, the "clunk". May be a bad flex plate, check that before condeming trans for the noise. I hate to say this, when you put the trans back in did you get the converter drive hub properly indexed into the trans front pump? If you didn't, that would explain the noise ans odd operation. Lastly, think carefully, were any of these problems evident before the eng change? Offen we humans take a simple task and turn it into a nightmare. jim

[dbmx66]

i thought it might be a leak in the rad, but the coolant is still bright green, no trace of trans fluid at all.