Please help ... is my 4L80E damaged?

[stutaeng]

You will need a puller to remove the pump. Everyone (including myself) just stick a big flat screwdriver on the casting near where the red arrow is shown to gently pry out the pump. Be careful. The pump is heavy. Yes just remove the lockup oring, remove the bolts and pry out.

Get a new pump-to-case seal, lockup oring and the little seals on the pump bolts. It is recommended to install a bit of RTV on the bolts when installing as extra precaution to prevent leaks at the bolt heads.

I'm still confused though. Have you determined that the transmission is not burned up? Remove your oil pan. No sense in changing the front main seal if you find all the clutch material is on the pan...

How many miles or Km are on your truck BTW?

 

[seza]

The mileage is about 350K,
as for the state of trany, I went about it the wrong way started with difficult bit and left easy bit!
I should have dropped the pan first but I went for the seal - that turned out to be ok.

what worries me more is the fact that the reverse is one that is proving problematic.

 

[Schurkey]

Perhaps a moderator will move this thread out of the ENGINE section and into the TRANSMISSIONS section.

 

[BeXtreme]

Often reverse is one of the first things to burn out when you run them low on fluid. It is one of the most common causes of transmission failure. It doesn't help that the factory dipstick might have full at the wrong level to begin with. Pull the pan, see if the pan is full of junk and the fluid smells burnt. Then check to make sure the dipstick has the full hot level even with the pan rail. I have seen factory dipsticks with markings up to an inch too low. That, combined with you needing to add 4 quarts after your trip, means you could have been up to 6 quarts low on fluid while driving. I'd be very surprised if it didn't burn up at that low fluid level.

 

[seza]

Thank you all guys for your constructive input and sorry for posting in the wrong section,
just to recap ... 4L80E with a GM6.5TD on a 1994 burban been loosing ATF for little while I kept topping it up,
up to few days ago when she refused to go into reverse and sometimes even forward:
1. we dropped the trany, it seems like the loss was coming from the sump seal, the main oil pump seal looked OK
2. the oil in sump looked black and had some powdery residue (no larger chunks)
3. when poring oil it "glisten" in the light - indicating metal powder mixed in
4. the magnet at bottom of sump was covered [see pics]

My questions to you guys with experience of these beasts:
what are my chances of success if I put it back together again with good seals, oils etc ...?
where is the metal shaving coming from? the oil pump?
if so can it be rebuilt? easy? difficult?
I am in N Africa, we have little access to parts and mechanics here no experience rebuilding auto tranies let alone US ones
having said that - if there is a kit that can be installed easily without much equipment/calibrations then I can order it
off say Rockauto or where ever?

PLEASE HELP ... AM STUCK!

THANK YOU.

 

[seza]

bump

 

[Schurkey]

That magnet doesn't look too horrible to me. The metal there is probably stuff worn off of the clutch steels. No big pieces in the pan is a hopeful sign.

If this were me, I would pull the oil pump seal to verify that the converter bushing hasn't moved forward. That was a common problem on Ford transmissions. The bushing would move forward, blocking off an oil-return hole. The fluid at the bushing had nowhere to go but out the front seal. If you're CERTAIN that the front seal isn't leaking...you'd better find out what was.

There's about a dozen leak-points on a transmission. Most of them drool downward and look like a seeping oil pan gasket.

If I were stranded in North Africa, I'd clean the pan and magnet, put it back together with a fresh filter and 5 quarts of fresh fluid, and drop the lower cooler tube at the radiator. Add a section of hose to the tube, so you can direct the spray into a drainpan. Open ten more quarts of fluid, and put them within easy reach. Start the engine, dump fluid down the dipstick tube as fast as you can pour it. When the fluid coming out of the tube, spraying into the drainpan looks virgin-clean, shut off engine, re-connect cooler tube. Top off fluid as needed. GET THE FLUID LEVEL AS CLOSE TO "RIGHT" AS YOU CAN. Then hope for the best. Drive it--if it will go into gear--get the fluid warmed-up, assure the level is correct.

If that doesn't work...you're in trouble. The Turbo-Hydramatic 400 that the 4L80E is based on is one of the easiest automatic transmissions to overhaul. All the clutches in front, all the gears in back, no clutch pistons in the case, no devastating problem areas in normal use. The 4L80E is going to be more-complex, more pieces, more precision, and more electronic. Not a good combination where you are.

Beyond that, there's entire service manuals dedicated to pressure testing, solenoid testing, (do you have access to pressure gauges and a multimeter and scan tool?) teardown, inspection, and reassembly.

There's also this--I haven't read it, I don't know if it's any good. And I refuse to buy a Printed-In-China book at Printed-In-USA pricing, especially with SA Design's formula of small photos and too-few pages. So I'll be waiting a couple of years before I buy a used copy.

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Good luck.

 

[seza]

Schurkey, thank you for that,
I think the leak is emanating from either sump seal and/or oil pump lower bolts
the issue we are having - the front seal (oil pump) is proving difficult to remove from the front,
is there any easier way?
if we pull out the entire oil pump to expose all the gearing inside for inspection would that cause a problem?
would we loose any calibration?

 

[stutaeng]

You need to hit that seal lip with a flat head screwdriver and hammer and start deforming it. Work around it and it should eventually pop off. The leak may be from the pump-to-case seal or the bolts may be leaking, as I pointed out on my eailer post.

By the way, this is what a burnt up transmission looks like when you drop the pan.

You must be registered for see images attach

If you decide to rebuild it I posted some information that may be useful to you on this thread:https://www.gmt400.com/threads/99-silverado-4-3-to-5-3-swap-with-4l80e-bonus.51060/page-4

I didn't see any metallic particles. The magnet looks normal. A bit of that black paste-like material is normal.

Remove the pump since you know it's leaking. There's no calibration to reinstall. Inspect your pump bushing, but with many miles, it's likely going to have wear. How does the hub of torque converter look like?

 

[seza]

wow ... what a helpful bunch, thank you all guys,
the mystery deepens with this ol girl !?

... bit of background to the issues - I am having:

I drove here to N Africa from Spain about 2 months ago, no problems,
here there are multiple hazards on the road, especially slow speed bumps that you can even find
on InterState highways!
I must admit I went over few of those at considerable speed - at one of those it caused the
trany unit to break at the two upper bolts [pics]
that probably explains loss of traction and shuddering when in OD mode that I experienced intermittently for at least a month,
I even posted something about it on a different forum.
Not aware of the breaks I changed the oil [ATF] and filter but I reused the old sump seal [not a good idea - I come to realise],
after that I kept loosing fluid and topping it up and driving on until couple of days when she lost the reverse and even forward motion was difficult,
adding fluid made very small difference and finally we dropped the trany and discovered the breaks,
here is the thing ... the copper shims around the oil pump looked ok ... I though as a result of bolt break that would destroy the shims

we are going to weld the thing and put it back together again as advised by you good guys ...
but I am at loss here .... none of the issues explain the loss of gears?
and I my other question ... in the pic of the side of pump [finger pointing to], is that a seal that need replacing or is it a ring of some sort that should be left alone?

what are my chances of getting this ol girl back on the road?