How to reseal the 6F55 transmission.

802SHO

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Now that I’ve sealed up the transmission twice I think it would be a nice gesture to share how I went about doing it. Tools needed. Permatex automatic transmission gasket maker, shop towels/rags, 3m “moderate” stripping pad, razor blade, optional pick, Acetone, shop vac, gloves and optional but recommended digital torque wrench and pneumatic fluid extractor. 25B7EA43 97AE 4236 83BB CFD8E2ACA57FE3CF11A5 7B23 42D2 A798 D7503079306A6637B033 3BFB 40B5 B11F B728594D452C41568FBB 3524 4FDF 9D2C 3E9518270E50
First thing you’re going to want to do is hopefully have the trans slightly off the ground and get yourself sitting on a small creeper/roller seat instead of on the ground on your knees. A table would be even better if applicable. Start by using the razor blade and shop vac, slowly scrape away the old gasket maker residue 9AC68A9D 06DC 4FDE 893A 91121A88236E4A5ED3DA D73F 4676 9FCB E93C05630470
Until you’ve got it pretty well cleaned up. The vac to catch as many small particles as possible from landing inside the trans as you work your way around. Not a bad idea to go ahead and take out the front diff and pinion gear set and set aside on some towels.22F71415 AEDB 4696 9F5B 002CAED49A07
From here cut a smaller piece off the 3m medium stripping pad and work your way around, still vacuuming as you go to keep trying to keep the inside of the trans as clean as possible. Once done it should look similar to this.F5125A8D 38D1 46BD 9746 69A31DE2A059
Now you’re going to clean it up with Acetone and a clean shop towel/rag. It will look nice and clean like this.A9A26C9A 99E6 4DD3 82BA DEA3EE677A6F
Now this is where I decided to also drain out the old fluid that also might contain anything that could have accidentally fallen in while getting to this point.BA289600 49E7 46BC 9472 AB1E31CE545B
This is the same thing I did for the other half of the trans and got it looking the same way.0AFE2F29 F771 417E 8E62 5A8C40AEC6FC
No need to rush through this. Take your time and be thorough. Now take the gasket maker and lay a fairly small bead all the way around, and try to also get some around the bolt holes as well. This time I chose to lay the gasket maker down on the oil pump side.88CADE9C 26CA 409C 9A46 1D49BB17EE95
The next part is pretty critical and where you can run into alignment issues. The pinion gear and diff intertwine, you’ll need to put them in at the same time, they can only go in one place and if you try you can rock them around, however they should stay in one spot and lay pretty darn flat. Old pic for reference.867BB399 5263 46F9 B9EF 423D59B4AB38
This shaft pin can be removed and may be stuck to the other side of the trans. I prefer to have it on this side, through the diff and slightly sticking out. B59EE83C 020F 4D43 BB99 EDF37F27AFAB1F46FCC8 BBBF 4ACA A041 0FBCF35E6FFF
Next thing you may notice is this inner ring found on the reactor could be on the diff side, or it might be on the reactor side. I prefer to keep it on the reactor and if it’s not there, pick it up and put it here, and slowly lower the reactor side on the diff side and it won’t fall off, but if it does fall off it will throw off the alignment of the two halves seating properly.BFE890E9 FA43 4CA2 BEBD F82E494D18C1
There are two dowel pins as well, which should really only aid you in alignment. But there’s one more potential issue putting these two half’s together. It’s possible this gear needs to rotate slightly.10FC1FEA CEB4 4B2F 9D37 81E63F873657
You’ll know that’s the case when it seems like it’s about 1/4” from fully seated and seems stuck. Lift it back up only to get a hand in there and rotate it one tiny turn. Lower back on and wiggle that side of the trans and it should finally fall into place.

Now you’re going to want to hand thread each bolt back in hand tight in a large cross pattern. Next you really need a digital torque wrench. I torqued the bolts down to about 16 ft/lbs in a cross pattern. Waited about 5 min to let the gasket maker setup a little more. Then I torqued all the bolts to 38 ft/lbs in whatever cross pattern I came up with, finishing up by checking them all once again. You should end up with a nice bead of gasket maker that flows just outside the seal all the way around. 9359C1E5 E696 47D3 BEE4 3A9D5120FAA9
At this point it should be safe to put the trans back in but you shouldn’t add any fluid for at least 24 hours. I’m going to take it a step further and let it cure for 24 hours before I even get it sitting up straight on a hoist and in the car. Just in case any residual fluid could possibly pool on the bottom and not allow the gasket maker to do its job.

Hope that helps anyone in the future possibly doing a limited slip front diff conversion modification.
 
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bpd1151

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A stellar, well written "How-To" tutorial.

@ADMIN ...... can this be placed as a "sticky" into the maintenance section for the GEN4 / GEN5 area?

Can't remember if there is still a "How-To" section since the revamp, but maybe added there too.
 

76FoMoCo

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Thanks for the write up!
Did a drain and fill yesterday and found above average brass shavings in the fluid. Now what is brass in the 6F55? :(
 

Bronco2fan

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Man, you are way too ambitious for me. If I only had half your energy and knowledge, I'd be in the poor house lol. Keep it up, it's definitely good reading.
 

FrankK

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802SHO,

Good job, everything looks great. A couple of questions.

Did you do all this work yourself? How much do the halfs of the transmission weigh?

Frank
 

802SHO

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802SHO,

Good job, everything looks great. A couple of questions.

Did you do all this work yourself? How much do the halfs of the transmission weigh?

Frank
Yes I removed my trans by myself with a hoist. I set it down on a spare pallet. I think the whole trans weighs close to 300 or so. It’s awkward too. First time was picking up my used trans which is the one that is pictured above and now has the limited slip diff. Im saving my original trans to use as my official transmission build.

I had the used trans sent freight to UPS close by. They loaded it in the bed of my truck with their forklift. When I got home I used a ramp I have to load and unload my sons 110cc dirt bike. I slid it down that slowly. From there just sliding it around on a pallet, up on the hoist and it’ll go back in. I pick it up by leaving the top trans mount attached and running a cable through it.

The side of the trans with the clutches, ring/pinion and valve body is definitely the heaviest. The other half or bell housing side is a lot lighter. I pick that side up and move around, it’s the half I pull off and the half I put back on by myself.

Pretty sure I can just pick up the whole thing but I don’t see any reason to do that lol! It’s awkward and I’m passed my ego years where I would pick it up just to prove it. I don’t think I’ll be walking around with it and putting it on top of a table. I’ll just slide it around on a pallet and use a hoist lol. Work smarter not harder is a mantra I tend to execute more consistently these days.

Not sure if you meant if I did all the work so far on the trans myself. I had my cousin from NH over and he helped me open my trans. He helped me open my ptu. I’m always happy to have a helping hand especially when it’s free! Messing around with the valve body swap, the resealing and diff conversion stuff I did by myself.
 
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FrankK

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Thanks 802,

Doing what you do, you show everyone what one person can actually do. And that they shouldn't be afraid to try to work on this themselves.

Thank you,
Frank
 
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