Welding transmission case

[Mach1]

My 3550 case has 2 cracks in it near the top/front ears, I went to buy another later model tko500/600 case and it had a crack in the same spot on one side.

I am just going to weld the cracks in my case, my plan was to drill a small hole at the end of the cracks, try to vgroove the crack a bit, weld it up, grind it flat, then weld a plate on top of the crack to reinforce it a bit.

Does anyone have any advice on cleaning up the case for welding? I was going to heat it up with a propane torch to try to get some of the oil to seep out then hit it with a abrasive wheel, then clean with acetone. My previous experience with welding aluminum that had contact with oil was a bit of a disaster. Any tips or tricks would be great

[Chas_svo]

My 3550 case has 2 cracks in it near the top/front ears, I went to buy another later model tko500/600 case and it had a crack in the same spot on one side.

I am just going to weld the cracks in my case, my plan was to drill a small hole at the end of the cracks, try to vgroove the crack a bit, weld it up, grind it flat, then weld a plate on top of the crack to reinforce it a bit.

Does anyone have any advice on cleaning up the case for welding? I was going to heat it up with a propane torch to try to get some of the oil to seep out then hit it with a abrasive wheel, then clean with acetone. My previous experience with welding aluminum that had contact with oil was a bit of a disaster. Any tips or tricks would be great

There is a specific grinding disc to use for alum. Don't use anything steel on it. Acetone or any good cleaner/degreaser is a good start. It's very hard to make a welded fix stronger than it was without some added thickness or bracing.

Good luck.

[Matt]

Preheat for sure. Preheat a lot of the area around the spot you are going to weld. If it cools off too quick, then it will just crack again

[thesource]

It's a pretty common repair on the Tremec cases. As long as you get the bolt hole back in line and the surface that mates to the bell housing flat, its not really an issue other than looking like shit.

[Mach1]

It's a pretty common repair on the Tremec cases. As long as you get the bolt hole back in line and the surface that mates to the bell housing flat, its not really an issue other than looking like shit.

Any ideas on preventing the crack(s)?

[TexasT]

I'd drill the ends as you stated. Get a new wheel and don't get anything else on it.
Clean, clean, and more clean.