Broke a 4L80e mounting ear

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Daveo91Burb

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Good news: I dropped in my 383 today and with some effort and monkeying around we got it on the motor mounts with bolts thru them. And then it seemed to be pretty easy to get the tranny to line up. Got the lowest bolts in on both sides, not too much trouble. Then next one up on passenger side, no issues either. But the next one up on DS there was a 1/16” or less gap and since I couldn’t see the gap while I was torquing the bolt I ended up cracking the mounting ear. CRAP. That’s the bad news. Really bad???? Options??

Get it TIG welded? JB weld? Got that from a multiple google searches - not sure I’d go that way. If I get the ****** out from under the truck I think I’d get it fixed right. Hopefully it is fixable? And I’m not thinking I’d go this way, but what’re the consequences if I just run it with five bellhousing bolts?

And I saw on another site someone said the guy that did this same thing ruined his front pump. I think I’m OK there - I made sure the TC was pushed all the way back and I had it zip tied to hold it in position. I think my misalignment is from just a little slop in the motor mounts, even though they’re new.
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Many times I've seen only 5 bolts installed (or less) and everything was functioning fine.

However, I'd be very concerned about what caused it to bind and break when running the bolt tight.
 

Daveo91Burb

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Many times I've seen only 5 bolts installed (or less) and everything was functioning fine.

However, I'd be very concerned about what caused it to bind and break when running the bolt tight.

Yeah, I haven’t gone out to verify but I think I know why now. Before I even pulled the old motor I pulled t-case because it needs its input seal replaced. I ended up putting the cross member back in to support the back of the tranny without a jack stand. (Front supported by jack stand after motor pull) But I don’t think I bolted down the mount - it’s just sitting up there and it might be a tiny bit cockeyed. Possibly just enough to cause the gap I was seeing. Big price to pay, stupid mistake.

Thanks. I’m going to sleep on using 5 bolts. Not a big fan of doing things that way, but time and budget might dictate.
 

Obwonkonobe

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Who ever sold me my truck didn't tell me that my trans had the same problem(look at the passenger side). So naturally I beat on the thing like it owed me money for 6 months until the trans went out before noticing the cracked ear, you should be fine.

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Daveo91Burb

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Who ever sold me my truck didn't tell me that my trans had the same problem(look at the passenger side). So naturally I beat on the thing like it owed me money for 6 months until the trans went out before noticing the cracked ear, you should be fine.

Cool, thanks. So trans went out for other reasons? Missing bolt/chunk out of bell housing had no effect?
 

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I would be tempted on finding on someone to weld it, but likely the whole transmission has to come apart to not oberheat things. Or just leave it alone/add spreader plate and a longer bolt
 

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I would be tempted on finding on someone to weld it, but likely the whole transmission has to come apart to not oberheat things. Or just leave it alone/add spreader plate and a longer bolt
Is it just one ear for one bolt hole? Did it break off clean? Meaning, can just put the piece back in like a puzzle piece and it fit good? If it's just one bolt hole and it fits back in there like a puzzle piece it, just JB weld it and call it a day. For real. I had one do that on a Th400. Actually it was a build I did and the guy said he'd get another core and told me to keep that one for spare hard parts. I JB Welded it and used it. It was even holding strong when I pulled that transmission back out months later and is still holding to the this day. I might even have pics of it somewhere. The piece is almost as big as a pack of smokes.
 

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Is it just one ear for one bolt hole? Did it break off clean? Meaning, can just put the piece back in like a puzzle piece and it fit good? If it's just one bolt hole and it fits back in there like a puzzle piece it, just JB weld it and call it a day. For real. I had one do that on a Th400. Actually it was a build I did and the guy said he'd get another core and told me to keep that one for spare hard parts. I JB Welded it and used it. It was even holding strong when I pulled that transmission back out months later and is still holding to the this day. I might even have pics of it somewhere. The piece is almost as big as a pack of smokes.
:pics-stfu:
 

HotRodPC

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Can't seem to find them. The story on that one, this guy I was building a trans for bought this core. He brought it to me telling me he bought it as a working transmission off Craigslist but it didn't work. He called the guy up wanting his $100 back. The guy said Sorry, done spent the cash and he didn't know that he got it from a friend and was told it was good. I immediately said, ********, then why did he paint it this awful silver and about 6 coats. The **** is so damn thick and he painted right over all the grease. Back at the ranch. I took it to a machine shop to have cleaned after I stripped it down. Machine shop calls and says I need to come see this broken case. After the paint and grease came off, the piece was barely hanging from a piece of packing tape. The dude knew it was broke, taped it and painted it to not look broke. I thought I had pics of that too, and the repair I did to it.
 

Daveo91Burb

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Thanks for all the help guys. It fits like a puzzle piece although I can’t see the entire crack line. I’m pulling it this week ( trying to decide on either buying or borrowing tranny jack - guy at work has one) and hopefully good ol JB will do just fine.
 

HotRodPC

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Thanks for all the help guys. It fits like a puzzle piece although I can’t see the entire crack line. I’m pulling it this week ( trying to decide on either buying or borrowing tranny jack - guy at work has one) and hopefully good ol JB will do just fine.
If that's the case, I'll think you'll be fine. I honestly had no faith in the JB Weld, but it did surprise me. So long as it holds that piece in place, then it's there doing what's it's intended to do when you put the bolt through the hole and clamp down on the bellhousing against the engine block. The thick heavy guidepins are what is holding most of the weight once the bolts are snugged up.
 

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Thanks for all the help guys. It fits like a puzzle piece although I can’t see the entire crack line. I’m pulling it this week ( trying to decide on either buying or borrowing tranny jack - guy at work has one) and hopefully good ol JB will do just fine.
If you have wood longer than the width of the pan you'll be fine to use a standard jack, I just pulled my th350 like that and will install a 700r4 the same way in a few hours
 

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do not JB weld it, that isnt fixing anything. Have it tig welded if you cant do it.

There wont be any problem with tig welding it together with the trany together, if your concerned about heat, put a wet rag down by the pump to get rid of any heat. if it were min, i would grab a piece of steel flat strap about 1/2" thick, clamp it across the flat surface wher it meets the motor, clamp the broken piece in place and tig weld it up. On the thicker areas i would grind the alum into a "V" shape and tig weld that up so i penetrates all the way through.

i would also find out why it was binding up, it shouldn't break just by having the trans a little low in the back when you bolt it up, was there something pinched in between the block and the trans, converter not in all the way? there should always be a little room between the converter and the trans when it trany is bolted up and the converter is loose. you should be able to spin the converter by hand.
 

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I'd agree, tig is best but JB Weld sure as hell fixed mine to my surprise. I'm pretty damn sure that's the transmission I ended up putting in my own truck because I damn sure wouldn't sell it to a customer and it's been in there for several years now. It was 1 bolt hole and a chunk I'd say just smaller than the size of a tennis ball. It's not a daily driver by any means, but it's been driven plenty and hasn't fallen out yet.
 

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