crack in transmission case

[jcal87]

my tranny was leaking pretty bad so i pulled it out thinking it was a seal and turns out i have a hair line fracture in it can you weld this shut or jb weld it shut for a temp fix

[jcal87]

also it is a muncie 4 speed m21

[98ssnova]

As a temp repair I guess so but your case has damage and will only progress and get worse I wouldn't want a gear fraging out through the at 70 mph . I could be wrong but you need to address this ASAP. If you are driving the car daily.

[jcal87]

is there any kind of mig weld i can do on an aluminum case?

[98ssnova]

I would imagine that you could but with all of the rotating that goes on there is some pressure that builds up. Brfore you have it welded I would get it checked for cracks. Honesly buy the time you get done with this you probaly could have just bought a very nice used one. Just my .02:cheers:

[War]

I would imagine that you could but with all of the rotating that goes on there is some pressure that builds up. Brfore you have it welded I would get it checked for cracks. Honesly buy the time you get done with this you probaly could have just bought a very nice used one. Just my .02:cheers:

That's a nice way to say quit while your ahead

[jcal87]

well it is cracked and i own a welder but can you mig aluminum or can i jb weld it

[98ssnova]

OK bro well weld it up and run it I am not a pro welder but i though you just put a brand new motor in your car and I'm sure it has some power. When that get transfered through the tranny it will over time exposed the weakness in the metal. But please weld it and I hope it lasts forever but if it doesn't sorry for your luck. Also have you figured the cost of removing all the gears and plates in the tranny I'm sure you wouldn't weld it with all of that still in the case. BUt good luck to you sir.:thumbsup:

[jcal87]

well i figured when welding aluminum low voltage is a must and didn't think it would effect the gears inside the casing but if you think different please tell me that's why i posted on here to learn but the engine is not new by any means and this car is not a daily driver i just need it to get by until one day i upgrade the engine and tranny

[Vegas69]

Sounds like you found your noise.

[jcal87]

lol ya i think so

[98ssnova]

Well then weld it up and let see whats happens. Not trying to be a smartass:cheers:

[68protouring454]

you will need to pull it apart and clean both sides very very well. the heat will attract the gear oil/fluid and contaminate the weld quickly. also you want to watch heat input, but you also need to have enough to weld properly.

[98ssnova]

:yes: :yes: This is why I was telling it might be cheaper to find a nice used one.


you will need to pull it apart and clean both sides very very well. the heat will attract the gear oil/fluid and contaminate the weld quickly. also you want to watch heat input, but you also need to have enough to weld properly.

[jcal87]

yeah i have started looking i posted a wanted ad on here to

[JodysTransmissions]

I would suggest getting a new Autogear Supercase. They are a lot more beefier than a stock case. I have seen cracks turn into broken gearsets.

TIG welding is the best method for this job. To do the welding on the case, you should tear down the trans if you choose this option.