Leaking water from the trasmissin

Need to know year and make of vehicle,but oil should not be coming from water pump mounting bolts ,check to see if oil is leaking from above the water pump .it may be just accumulating on water pump .steam clean engine and check, you could remove the bolt with oil around it take a mirror and check to see if the hole goes into crank case or if it's a blind hole ,if it goes all the way threw oil is running down into hole around threads of bolt and out to where you see it , when you replaced water pump do you remember seeing anything on the bolts (RTV, blue or orange color lock tight, if so remove bolt put RTV on bolt and reinstall it(if you decide to use lock tight do NOT use red the bolt will not come out ever again, make sure you use blue lock tight!!!

There is definitely no valve there - the only pressure relief valve would be inside the radiator cap. What you see is leakage from a water pump bolt or from the water pump itself. You could try applying a waterproof sealant to that bolt, but it's tricky - allow the engine to cool FULLY, then remove the bolt and hold your finger over the bolthole while a helper applies sealant to the bolt threads. Quickly put the bolt back in the hole so you don't lose very much coolant, tighten the bolt again.

If that doesn't do it, then the leak is really coming from the front seal of the water pump - meaning the water pump needs to be replaced.

You won't really know until you can see the bottom of the pump. Most pumps have a "weep" hole where coolant will leak from if the seal goes bad. It can leak and still function without symptoms until the bearing goes.

usaully a hole near the shaft of a water pump is a weep hole and if water or antifreeze is coming out, your water pump seal is bad and pump needs replaced.

a lot of stuff to fix here
oil: with the truck running hot, I would use a heavy oil, like 10-40
trans: where is the leak? If pan, tighten bolts. seals are much harder repair
water leak: possibly a freeze plug. Maybe you should pull the tranny and fix the water leak and the trans seal at the same time (if the seal is bad)
overheating: maybe just caused by the leak. Hard to tell until the leak is fixed. Might want to check the radiator for sludge and back flush if dirty.
hard sound: probably loose flange seal at exhaust manifold. check hole exhaust pipe to locate leak. If not along pipe, unbolt the flange and put in a new gasket.
engine problems: is the engine light on? If yes, have the truck scanned for trouble code and report them back to us. Autozone does free scans.
More questions, please let us know

There should be a tube that comes up from the auto trans with one tab to secure it to the bell housing bolt (trans bell housing bolt goes through tab, then through the bell housing) to the engine block. Pass side.

Sounds like your water pump is leaking and your engine is overheating due to the lose of coolant.have someone top off your cooling system and pressure test it to find the leak.Which I am thinking is the bearing hole or Intake gasket corner which are both common on these vehicles.

you have water in the trans lube drain the trans and refill.

What you are seeing is the water pump (often mistaken as an idler pulley). It is a very simple change. Remove the belt, loosen the two bolts on the water pump ("diamond shape with pulley on front"), pull the water pump out, and reverse steps. You may want to drain your coolant into a very clean or new bucket first or you will loose good coolant when you pull out the pump. Once water pump is in place, replace belt and your good to go. Tools needed : Belt removal tool or 3/8 inch drive/ratchet with extra long hangle or cheater bar, and i believe a 10 or 13 mm socket for the pump. NAPA carrys a lifetime warranty pump...i suggest it.

you have a leaking water pump... there is a "weep" hole at the bottom of it and when the inner seal goes bad it starts slowly leaking out of it as a warning sign to replace it. It will do that for a few days, or months even, until it starts leaking profusely.