4L80E Damage--Need Advice

[tom.mcinerney]

I think i 'sprung' my transmission case...
After R&R'ing the motor mounts [I jacked up the motor for clearance] i noticed (horrified) transmission fluid leaking from the rear of the case, vehicle stationary.
I assume i should pull tranny and inspect, maybe swap components to another case?
Any suggestions per procedure, or relevant TDP article reprints welcome. Particularly, I'm wondering if the entire case tends to buckle/deform, or if damage more likely localized, as at fastenings....
{This also posted to members forum-}

[britannic]

They're very strong cases and should move with the engine when jacked up - I've lifted my engine by about 4 inches several times without any tranny case problems. Did you check that you didn't snag/stretch/break a tranny cooling line? Is your truck a 4x4?

On my 4x4 there are 2 engine mounts and one adaptor mount for the tranny and t-case, so once the engine mounts are free, the tranny will pivot on the rear mount. If you have a 4x2, it may be different - maybe someone else can chime in here...

Check everything is tight, if the t-case is loose where it bolts to the tranny, ATF can drip out at the join.

[Johnny B.]

Could the fluid be coming from the tail "output shaft?" Can't imagine breaking a case and not hearing it snap.

[Uncle Wally]

Depending on which way you jack the engines (ie. lifting the drivers side) you can get oil out the dipstick tube seal. Especially if it has high miles and the rubber seal gets hard and brittle.

Waldo

[rjschoolcraft]

Seriously doubt that you have sprung your case. May have damaged the lip seal for the output shaft? May have a loose/poorly sealed pan? (Aside from the other good suggestions above).

[kowsoc]

Should be easy to locate the source of the leak. I suspect the dipstick tube O-ring. You may have bent the tube against the firewall when lifting. As mentioned, the O-ring, if disturbed will leak and the fluid may be running back along the trans before dripping off at the back. Have a close look.

[tom.mcinerney]

Many thanks. I will follow up each suggestion.