Cracked transmission case: Grassroots Motorsports forum: Grassroots Motorsports Magazine

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Oct. 22, 2011 11:27 p.m. fornetti14 HalfDork

I have a cracked transmission case. It's a 2005 Mazda 6i with a 5-speed manual.
I have fluid coming from inside the bell housing and it looks like something broke off the pressure plate, spun around and cracked/broke the mofo.

I'm going to yank it out and replace the clutch... plus the trans depending on what you guys/gals say. If it's a hole I know I'm replacing it. In fact, judging from the fluid that's coming out of this thing it might be a total loss.

Anyone JB weld one of these?
Oct. 22, 2011 11:35 p.m. mad_machine SuperDork

I take it you are out of warrenty?
Oct. 22, 2011 11:41 p.m. fornetti14 HalfDork

Bought it used and never had a warranty. The car is really nice and worth fixing. It's just going to be a PITA for me.
Oct. 23, 2011 8:12 a.m. Don49 Reader

I have successfully welded transmission cases. If the damage doesn't affect any critical operating area, it should be able to be TIG welded. You won't know until you pull it.
Oct. 23, 2011 11:15 a.m. iceracer SuperDork

Transmission shop fixed my ZX2SR with JBweld when the pinion shaft(spider gears) wore a hole in the case.
Oct. 23, 2011 1:39 p.m. N Sperlo Dork

Cracked the bell housing of my F150 with a wobble in the drive shaft at the output. Payed $600 on a rebuilt tranny and haven't had a bad shift since. Its a perfect time to add some lightweight toys in there.

Cheapest option, go get a rebuilt. (If it cant be otherwise fixed.)
Oct. 23, 2011 4:20 p.m. Twin_Cam SuperDork

A junkyard or rebuilt trans will probably be easier and may be cheaper (in the case of the JY route).
Feb. 2, 2012 8:35 p.m. JohnyHachi6 Reader

Any news on this? I have a cracked trans case and welded up most of the crack, but there are some areas I can't get in to with the torch and was thinking about just JB welding it to keep the trans fluid in. Any thoughts?
Feb. 3, 2012 5:48 a.m. fornetti14 HalfDork

It was more than cracked and had a time size hole in it. Pressure plate broke and sent metal bits everywhere. I just replaced it with a use one from a salvage yard. Car runs and shifts great now!
Feb. 3, 2012 6:20 a.m. JohnyHachi6 Reader

Oh man, sorry to hear that. Hope everybody was ok and minimal damage to the car. Glad to hear its working well now though.

I worry about that sort of thing myself having seen a few bellhousings where the flywheel let loose and decided I'll be running a trans blanket on this project car I'm working on even though I was able to weld up most of the crack in my trans case.