3FE Rear Main Seal (1 Viewer)

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jonheld

jonheld

Joined
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I'm reaching out to those who have done this on a 3FE equipped 80 Series. I'm looking for input and "gotchas" only learned by experience.

I will be in a very well equipped shop with a lift and rolling transmission jack, and all the amenities. I plan to drain all fluids and I have a new oil pan gasket standing by (OEM of course).

Any tidbits of wisdom would be welcome, as well as any parts I should order in addition to the oil seal.
 
Jon--

I would also do the input seal to the A440F while you are at it. Easy to access.

While the tranny is out, I would clean the filter and reseal the pan as well.

90311-42010 (seal)

00295-01281 (red FIPG)
 
You could order an h55 and bolt it up in place of the a440...

If you remove the rear main bearing cap you can easily remove and install the rear main seal by hand. detailed in this thread:

https://forum.ih8mud.com/40-55-series-tech/139889-h55-splitcase-into-02-79-40-series-2.html

Also, my 1992 fsm conveniently left out the two bolts connecting the top of the transmission to the engine in the section on transmission removal. they can't be seen from below and I had to access them with several extensions through the floorboard. I had to look in a 93 fsm to find out that they were there.
 
Pan was off and filter cleaned during the front end kersplosion. After 20 years with regular interval ATF drain and refills the filter and bottom of the pan were spotless.

I'll look into the tranny input seal as well.
 
bhmmapping said:
You could order an h55 and bolt it up in place of the a440...

If you remove the rear main bearing cap you can easily remove and install the rear main seal by hand. detailed in this thread:

https://forum.ih8mud.com/40-55-series-tech/139889-h55-splitcase-into-02-79-40-series-2.html

Also, my 1992 fsm conveniently left out the two bolts connecting the top of the transmission to the engine in the section on transmission removal. they can't be seen from below and I had to access them with several extensions through the floorboard. I had to look in a 93 fsm to find out that they were there.
Click to expand...

THAT'S WHAT I'M LOOKING FOR!!!
Thanks man. Any other "omissions"?
 
jonheld said:
THAT'S WHAT I'M LOOKING FOR!!!
Thanks man. Any other "omissions"?
Click to expand...

Not that I remember. The writeup in the FSM was actually so detailed and complete up to that point that it really tripped me up and cost me several hours of frustration. I thought it was just rusted together for some reason. IIRC the 93 writeup was exactly the same except for the addition of the step with those two bolts.

I also remember looking at the pile of parts I had to remove to get the auto out and thinking that I really hope the manual works so I don't have to put all that back in there. If I had known I was going to reinstall the auto I would have been more careful removing everything - lots and lots of bolts and parts have to come off.

Having a lift will make it exponentially easier. Needless to say the a440 doesn't easily roll out from under even a lifted 80 when it's sitting on a transmission jack.
 
as far as the torque specs I'm not sure if it is exactly the same, but the rear cap holds the seal the same way. The pan seals on the bottom of the rear cap and the rear cap holds the bottom of the rear main seal. I think I remember seeing that trick in one of the 62 h55 swap threads but couldn't find it with a quick search. I think there was also a thread in the 80 forum recently about the torque specs on the rear bearing cap.
 
I would also second the front pump seal as mine is leaking badly, but not badly enough to pull transmission. Just make sure(really important here ) to fully seat the torque converter if you do this.
 
krzyabncanuck said:
I would also second the front pump seal as mine is leaking badly, but not badly enough to pull transmission. Just make sure(really important here ) to fully seat the torque converter if you do this.
Click to expand...

The tranny is the ONE box that doesn't leak on my truck. I am somewhat hesitant to start screwing with it. My shop time will be limited and I need to get back on the road ASAP.
 
So at the end of day 3 of the rear main seal saga, the transmission is ready to go back in tomorrow. I severely underestimated the time involved for this job. Dealing with corroded and rusted parts adds days to the removal process. I should have figured this, but I was just being foolishly optimistic.

This is now the 3rd rear main in 240K miles. The first replacement was done around 100K miles under warranty by Caldwell Toyota in West Caldwell, New Jersey. It was installed incorrectly as it was not flush with the mating surface and slightly skewed as well. When they removed the original one, they did a superb job of trying to destroy the crank seal surface. It was gouged with screwdriver marks both on the rear edge and on the seal surface. What a fine job from a dealership by factory trained mechanics. This is why I never let anyone touch anything on my truck. Freaking idiots. Oh, and let’s not forget the missing transmission mounting bolt. Apparently the top passenger side bolt hole was too difficult to get to so they decided just to leave that one out. Pretty scary stuff.

Luckily, since the old seal wasn’t seated correctly, the new one is actually riding on a fresh spot on the crank seal surface and is further inboard of the longest screwdriver score mark. Dave and I both feel this seal should last a good bit longer than the last one. On a positive note, we had a chance to look at the lower half of the 4th main bearing and it was in pristine condition as was the crank journal. Not too bad for 240K miles over 21 years. Oh what a feeling. The motor is now sporting a fresh rear main, a fresh oil pan gasket, after spending hours cleaning the front and rear pan arch surfaces. I was never able to really get to the rear one before. Also I bought all new (22) oil pan bolts as every single one I removed was stripped. Once again, thank you to the previous guerrillas that call themselves mechanics. Also the use of hub studs screwed into the block in 4 or 6 spots really makes locating the gasket super easy when you’re trying to wrestle the giant oil pan into place. Spent a good half day cleaning all parts as well.

While the tranny was out I rebuilt the wiring harness and cleaned up all the connections to the unit, drained the transfer case oil, repaired any damages to O2 sensor wiring. Dave welded up the holes in the exhaust. Having all that room underneath really makes everything so much easier. If I had more time to spend, I would sound/heat insulate the transmission tunnel. That’s not going to happen.

Below are some pictures for your amusement.
1st pic is the old rear main.
2nd pic is the A440F and HF2a on the forklift.
3rd pic is the new rear main in and the tranny mounting plate going back on.
OldRearMain.jpg
A440FwithTransfer.jpg
NewRearMain.jpg
 
More pictures of stuff.
1st pic is a cleaned (sort of) and rewired tranny/transfer. The bar across the front is to prevent that pesky torque converter from falling out while we move the tranny around.
2nd pic is the flexplate and all associated spinny bits buttoned back up to FSM torque specs with red locktite.
CleanedAndRewired.jpg
FlexPlateBackOn.jpg
 
Nice work.
 
Is that Sasquatch wearing a flannel ?
 
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