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I want to clean my TH400 so I can paint it. It has 45 years of accumulated dirt and grime. The engine cleaners, brake cleaners barely make a dent.
I'm reluctant to use a pressure washer for fear of getting water in it. I have thought about media blasting it.... quick and easy.
I have also thought about taking it to Aamco to see what they can do.
What have you guys done??
Purple Power for most of it than mineral spirits and a good supply of different size brushes and some tooth brushes for those hard to reach areas.Also a few brushes that you can put on a drill. I would not blast the trans unless it was just the bare housing that stuff gets into everything and would wreck all the insides.
Meguiar's Mag Wheel cleaner (gray bottle). Soak it down, let it set until it's almost dry, soak it again and scrub with a stiff brush, rinse with water. I used it on an aluminum intake that was way nasty. Looks new again. On a trans, I'd plug the holes.
soak with your choice of degreaser, cap off all openings including vent tube and rear yoke, leave torque converter installed. hit it pressure washer it will be fine.
This is after 2 cans of oven cleaner from the dollar store and pressure washing. Then Gunk engine cleaner, Simple Green and a tooth brush.
I think I want to paint it...but aluminum seems too bright and "cast" seems too dark.... maybe a shade of grey.....suggestions??
Gunk (spray cans) and a pressure washer is about as easy as it gets. Just don't direct hi-pressure spray directly at any seals; otherwise there is no way to damage anything. Oh, seal up the vent at the top of the case; or remove it and install a pipe plug. If you remove the torque converter, you will have to seal off that input shaft area. Probably best to just use Gunk, garden hose and a brush inside the bell housing.
P.S. Don't do this on your driveway.....unless you want to shoot it after you do the tranny.
Last edited by 7T1vette; Jul 26, 2017 at 10:37 PM.
Gunk (spray cans) and a pressure washer is about as easy as it gets. Just don't direct hi-pressure spray directly at any seals; otherwise there is no way to damage anything. Oh, seal up the vent at the top of the case; or remove it and install a pipe plug. If you remove the torque converter, you will have to seal off that input shaft area. Probably best to just use Gunk, garden hose and a brush inside the bell housing.
P.S. Don't do this on your driveway.....unless you want to shoot it after you do the tranny.
Only way to do it. Scrubbing for hours sucks. I might soak it with Simple Green and then spray it off a second time. Gunk and the oil and grease it's removing leave the surface with a little residue, Simple Green or Purple Power will cut that and it rinse away.
I used lacquer thinner and a stiff brush on mine. Put the trans on a dolly with some newspapers underneath, and a couple of hours later it looked good as new...AND it made the rebuild MUCH more pleasurable
While I had mine out and clean, I painted it with VHT 'Cast Aluminum' color paint. I did wipe it down with lacquer thinner right before painting, as there was still some light film of residue on the surface...and I didn't want 'fish eyes' looking back at me.
And I'll bet it looked really nice once you finished too...real pretty sitting out there on the garage floor, sparkling like a TH400 diamond...an object d'art, am I right?
...and then you re-installed it, where it now sits, waaaaaay up in that trans tunnel "vault"...hidden for all time from any and all who could appreciate all of your work and efforts.
I know this to be true. For I too, have walked that path.
Orange: Did the lacquer thinner leave it that nice or did you paint it? Mine is clean but still looks dirty, I will probably paint it like 7T1vette did. I'm not rebuilding just filter change and replacing all of the seals.
Your project looks to be in about the same stage as mine. I took it apart years ago and now trying to put it back together.
The lacquer cleaning left it like that. I thought about painting it, but then rethought it when I realized it would be hidden from view once re-installed.
Even when you get under the car you can barely see the trans...just a little around the bottom and the pan is all that's really visible.
That pic was taken from earlier this year, and I'm happy to report that the car is officially complete and the trans works great after the rebuild...for which I am grateful, because this was my very first TH400 rebuild. I would not hesitate to do it again, either!
The lacquer cleaning left it like that. I thought about painting it, but then rethought it when I realized it would be hidden from view once re-installed.
Even when you get under the car you can barely see the trans...just a little around the bottom and the pan is all that's really visible.
That pic was taken from earlier this year, and I'm happy to report that the car is officially complete and the trans works great after the rebuild...for which I am grateful, because this was my very first TH400 rebuild. I would not hesitate to do it again, either!
Congrats, feels great when everything comes together and works as planned.
I rebuilt my 350, first ever, and just did the cam break in a few weeks ago. After weeks of getting it setup on a run stand and worrying if I missed something in the rebuild, it started right up. Now that was a good feeling
Cleaning a TH400
Only way to do it. Scrubbing for hours sucks. I might soak it with Simple Green and then spray it off a second time. Gunk and the oil and grease it's removing leave the surface with a little residue, Simple Green or Purple Power will cut that and it rinse away.
its clean now