Assembling an automatic transmission - GIF

[Altair]

Assembling an automatic transmission.




Previously:

ZF 8HP70 8-speed transmission cutaway - photo
Aisin AA80E eight-speed transmission cutaway - photo
Hydra-Matic 3L80 transmission cutaway - photo
Split transfer case - GIF
Go-kart continuously variable transmission - GIF

[Frank S]

She did real good until right at the end while tightening the pump housing. I'll wait to see if there are any gearheads who saw what I saw before explaining

[bob_3000]

She did real good until right at the end while tightening the pump housing. I'll wait to see if there are any gearheads who saw what I saw before explaining

I remember watching our auto trans guy doing "shift kits" for our late 60's street cars (Mopars) and the only difference I remember is Gerry used a screw driver at the end, no power tool and that didn't look like a good tightening pattern.

[mr mikey]

You got it.

[ductape]

She did real good until right at the end while tightening the pump housing. I'll wait to see if there are any gearheads who saw what I saw before explaining

Using an impact driver to randomly slam the bolts in instead of using a torque wrench with the right sequence?

[Frank S]

Seems like the ones who posted caught the problem as I saw it right away.
While I don't have a problem running down the fasteners with a power driver as long as it is just to run them down but you have to take note of the shape and pattern the fasteners are arranged, and running them down in a sequence just to touch or lightly snug usually this is done in a somewhat circular pattern radiating out from the center but alternating to the opposite side of the circle like drawing a multipoint star without raising the pencil each point would be the next fastener to run down then the sequence should be repeated in 2 or more torquing stages.
On assemblies where a gasket is incorporated not following a proper sequence or following torque procedures can cause the gasket to be crushed in one area and not in another castings have been cracked and assemblies ruined... When there is a matting boss and O ring is used the tight machined surfaces can be damaged if a single fastener is run down tight while the others are still loose again possibly ruining the components, I whenever possible prefer to lightly tap the assembly together until it is fully mated before running down the fasteners.