Broke another flexplate, what am I missing?

[idahovette]

I have a real hard time getting rid of anything..(just ask my bride) You never know when your tastes are gonna change, so think it over before you sell ...... you may find another square to buy that you need them for!!!!

 

[82sbshortbed]

I've got another th350 in the garage and was wondering if I should rebuild it to how I want or should I look for a th400 because of the BBC 454 in it now. I came across this article and think I'm gonna go ahead and build the one I have in the garage.

https://www.hemmings.com/stories/article/th350-transmission-swap

I've never done it but, think I can handle it and seems fairly inexpensive to build one to handle 400+ hp.

An interesting read tho

 

[Rusty Nail]

I’ve got 2 setups, this is with the stock 235/75/15’s. I have a second set of wheels where I am running 285/75/16’s out back and they don’t chirp as bad, but they are also like 3 or 4” TALLER, they help tone down the rear gears which is a huge part of why I run such a large back tire. It coasts around 3k rpm on the highway with the 285/75/16’s as opposed to about 3,800 rpm with the 235/75/16’s. I experience A LOT of wheel hop with the 285’s, so I don’t really do anything crazy with the bigger tires on.

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Wheel hop huh?
Go on...
It...hops?

 

[79dentside]

Wheel hop huh?
Go on...
It...hops?

Yep. I really don’t want to put caltracks or traction bars on because I don’t ever race it, but there are times that I get wheel hop if I goose it a little too hard off the line and the tires slip, the axle will wrap a little.

 

[Ricko1966]

Pix?

I'm sorry I didn't know was going to be a quiz. JK. Never thought to take pics when I did it, but when the snow melts I'll go mock everything up the way I did it. Basically I built a table under the truck like 18 inches wide 5 foot long turned sideways under the truck.I pulled the transmission backwards onto the table then lowered the table 1 side at a time to the ground.Then slid the transmission out under the drivers door. Even left the drive shaft in the transmission and just drug it out with the transmission. No mess I put it in on the same ramp I was using scissor jacks to raise and lower each side until it was real low then it was just my arms. But seriously this was so much easier than trying to balance the transmission on a jack and get it under the truck, or try to wrestle the transmission on to the top of the jack under the truck. The transmission was sitting on a stable platform the whole time I just had to slide it around.

 

[bucket]

Yep. I really don’t want to put caltracks or traction bars on because I don’t ever race it, but there are times that I get wheel hop if I goose it a little too hard off the line and the tires slip, the axle will wrap a little.

Something else is going on to cause that I think. It's not normal to have a wheel hop issue, no matter the tire size. Maybe look for some cracked leaves.

 

[Ricko1966]

Something else is going on to cause that I think. It's not normal to have a wheel hop issue, no matter the tire size. Maybe look for some cracked leaves.

Or a loose nut at the steering wheel.

 

[79dentside]

Something else is going on to cause that I think. It's not normal to have a wheel hop issue, no matter the tire size. Maybe look for some cracked leaves.

Yes you are correct. Before I lowered the truck, I had 2 broken leafs.

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Since it’s a heavy half, I just pulled them out and equaled the sides out as it had an 8 stack on each side. I’m not worried about it, just something that I thought I noticed a time or 2. Its got a spool in the diff, I could see that contributing. It skips the inside tire when turning anyways even when coasting, so it’s probably related. Now that I think about it, the time that I definitely remember the hop was on a turn where I was accelerating harder than normal to get up to highway speed and that was right after I got new tires and the spool so I probably just wasn’t used to how it handled when accelerating harder than I normally I would on a slower speed city street for the same 90 degree turn. I haven’t noticed a scenario that bad since, but I also now know how the spool/tires act on turns so I am ginger with it. I wonder how much of this “wheel hop” was just the tires skipping from the spool haha. The really old 235’s screech constantly on the majority of radius of a turn, the new 285’s grip harder and do kind of a repetitive/pulsing slip and grab deal until the turn is completed when making normal turns.

Or a loose nut at the steering wheel.

Might be a little heavy footed from time to time because the flowmaster’s just sound so dog gone good, but I’m certainly not a loose nut when it comes to operating a vehicle on the road.

 

[Rusty Nail]

Or a loose nut at the steering wheel.

Lolol - I see what you did there...very clever

 

[80BrownK10]

Lolol - I see what you did there...very clever

I didn't get it at first, till Op posted. I was thinking what does a loose but have to do with any of this. Haha

 

[79dentside]

Hey guys, just an update and a bit of humor for you all.

Ordered a flexplate and got it in this afternoon. Good idea whoever suggested the long bolt trick. That saved me BIG time and I will tell you why. I think I have resolved any guessing on why I keep breaking flexplates.

Basically, I was having issues with the tranny separating from the motor on the passenger side and was nervous about breaking the dreaded “repair” that we have all seen on my casing.. so I carefully ran a long prybar vertically in between the block and the trans to gingerly persuade it and then pieces fell off of the “repair”... I though, geez oh Pete, I’m in trouble. I had determined that this was a JB weld repair, but that is not the case at all. This was actually a cobbled aluminum repair that someone stuck BONDO over the top off.. BONDO ON A TRANS CASING!!!!

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Here is one of the bondo pieces that came off the corner of the bell housing.

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I then see a bead of weld from the ugly repair all the way back to the trans cooler line fitting. Trans was cracked and broken at one time. Someone welded what they could, then fabricated a mess of aluminum at the mating surface

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This casing has had a hard life, I am certain that all of this welding and junk is my misalignment issue that cause my broken flex plates.

So then when I try to get the trans mated to the motor again, it won’t go. I finally realized that the tail shaft was too high which couldn’t be the case since the trans was resting on the bolted in crossmember.... which meant the motor was too low. I raised the motor, then everything lined up right away. My thinking is the bad motor mounts caused extra stress on the casing which may have been why the casing cracked, which is why it was repaired, and is why said repairs are causing flexplate fiascos.

Conclusion... I am now sourcing a new tranny hahah.

Thanks for the help.