If a th350 pump goes bad. First thing to check is fluid level, first with the eng not running the level should be high on the stick. Then start the engine and quickly check fluid level again, if the level does not change pump may be suspect. If the vehicle moves at first then stops moving the filter may be clogged (a definite internal trans problem indicator) if a trans pressure gauge is avail ,test the port @ rear of pass side of case behind the round cover
M38 (th350)
That would be the 4L80E
Any Chevy transmission will bolt to any Chevy motor. At least RWD. 1955 to current. A 454 should really have a 400 transmission but a 350 will work. Depending on what you are putting it in there may be an issue with the driveshaft length and the yoke that goes into the trans.
If you have a Chevy 5.7 liter almost all Chevy transmissions 700r4 th350 th400 etc will fit. You can run a newer transmission 4l60e 4l70e or 4l80e basically they are electric overdrive versions of the older th350 and th400. the 4l60 and th350 is the half ton. The 4l65e is the corvette transmission and th400 and 4l80e is 1 ton. I believe the 4l70 is 3/4 ton and some half ton trucks like the ss and vortec max. the newer style transmission would need a stand alone controller which they sell and a aftermarket flywheel which will adapt the 2. Although all the bolt patterns are the same the 4l series one bolt on the top wont match up but its not a big deal and there are thousands of them out there. Your best bet is a beefed up 700r4 they can handle up to 450hp and don't need stand alone controller and have an overdrive. I would recommend a 2000 stall unless you have a rock crawler.
Pump assembly to case- (5/16-18) 15 ft/lb
That would be a 4L60E transmission. That is what belongs in the truck and came in that truck from the factory. NEUTZ.
If you are talking about where the driveshaft goes into the back of the transmission That would be called the transmission tail shaft housing.
That will be a 4L60E transmission.
4L60E
700r
Dextron
700r4