Broke another flexplate, what am I missing?

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79dentside

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I’ll be honest with what I could hear and see it looks fairly normal to me I didn’t really see any side to side movement. Wobbling I mean.

That case is a botched repair job. It looks like it was broken during removal or installing it at one time in its life.

The picture of the starter looks like something has been grinding against the nose cone.

If that case has been repaired in a way that miss aligned it to the block that is going to put it all in a bind.

I think if there is excessive play in the main shaft that it is a result of a mis alignment issue.

Meaning it caused the excessive wear and damage to the internal hard parts of the trans.

As I said before keep checking and eliminating the causes as you go.

I would think your next step would be to remove the trans and get a birds eye view of the back of the engine and the front of the trans. More than likely that botched repair spot and your symptoms are related.

Last question does it have a vibration at idle, under a load, letting off the accelerator while at hwy speeds.

Another words if you play with engine rpm or vehicle speed can you feel a vibration?

Before you pull the trans, fire up the truck with the converter unbolted (just at an idle) and see if your whine disappears and or is different.

Good input and you are making good progress keep checking I’m confident you are gonna get it figured out your on the right track.

I am thinking about just buying a used trans or maybe even a junkyard th350, then going and having it rebuilt or maybe even try it myself? This thing is rigged, but I can see why if the bell housing is part of the casing.. The picture only does it some justice guys, it is REALLY bad... it appears to be the whole section in between the top bolt and the bottom bolt when I was looking at it. I really don’t want to keep pulling the tranny because of damage/alignment issues now that I see this MESS. I will look at the trans because it’s coming out anyways, but I have accepted that I may have to look for a trans. Unfortunately, I don’t have a trans jack or the parts. I will acquire those and then go at it again, but the truck will be sitting for a few weeks before I can do anything more to it.

My buddy did have a trans jack so when we did this the first time, the trans stayed elevated under the car where we didn’t have the best light, but I didn’t notice it at all. Maybe he was trying to be nice and didn’t want to tell me that my transmission looks like junk lol.

On the converter, I notice more horizontal movement than vertical movement, but who knows.

I don’t have any major vibrations, I really have no complaints? It’s possible that I am not noticing something, the truck is very loud and rattles and vibrates everything anyways.

As far as the whine, it is so intermittent. In and out, I can’t just start it and immediately hear it. It randomly appears while driving.
 

BigDaddy72

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Ahhhh. Intermittent noises are always pesky.

As was said by others I think you are at the point of pulling that sucker (when time and equipment you feel comfortable with permit)

Lots of good advice here. I bought a th350 the other day off market place for $100.00

Not saying that is the normal price but if you find one for the right price you certainly could tackle the rebuild yourself if cuba is willing to walk you through it or anyone else for that matter that is a trans tech I’m sure between them and good ole YouTube you can rebuild it yourself.

Me personally I have zero experience with auto trans rebuilds. But would not hesitate to climb into one if the circumstances made it necessary.

I’m sure you can handle it when the time comes, especially with all the help and knowledge from the group of good folks here.

Best wishes buddy!!
 

Blue Ox

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His short bits came on one radio station i listened too in college. From the Golden Corner of SC. I always liked hearing them. That was the early 00s.

Mike Rowe is keeping up the tradition with his "That's How I Heard It" 'casts. Check them out, they're pretty good.
 
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Blue Ox

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I am thinking about just buying a used trans or maybe even a junkyard th350, then going and having it rebuilt or maybe even try it myself? This thing is rigged, but I can see why if the bell housing is part of the casing.. The picture only does it some justice guys, it is REALLY bad... it appears to be the whole section in between the top bolt and the bottom bolt when I was looking at it. I really don’t want to keep pulling the tranny because of damage/alignment issues now that I see this MESS. I will look at the trans because it’s coming out anyways, but I have accepted that I may have to look for a trans. Unfortunately, I don’t have a trans jack or the parts. I will acquire those and then go at it again, but the truck will be sitting for a few weeks before I can do anything more to it.

My buddy did have a trans jack so when we did this the first time, the trans stayed elevated under the car where we didn’t have the best light, but I didn’t notice it at all. Maybe he was trying to be nice and didn’t want to tell me that my transmission looks like junk lol.

On the converter, I notice more horizontal movement than vertical movement, but who knows.

I don’t have any major vibrations, I really have no complaints? It’s possible that I am not noticing something, the truck is very loud and rattles and vibrates everything anyways.

As far as the whine, it is so intermittent. In and out, I can’t just start it and immediately hear it. It randomly appears while driving.

You don't "need" a trans jack (there's that expression again :rolleyes:) to R&R an auto. You can use a conventional hydraulic jack and a section of 2 x 8, or 6, or 4 for that matter. Put the board over the jack pad across the pan and use the long bolt or threaded rod trick mentioned earlier to back it out and get it balanced.

Thousands of gearboxes have been pulled this way. Just take your time and exercise some judgement.

If you're feeling adventurous these vintage slushboxes aren't that hard to rebuild. They do require a few decent tools like larger snap-ring pliers, but if you can follow a manual they don't require Jedi skills to do a stock overhaul. If you run in to an issue just ask here. We've got some really experienced guys that can get you steered right.
 

Cuba

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Agreed. They aren't too bad to overhaul. But I've now grown a bit accustomed to a foot press and always had a floor trans jack & 2 ton press. There are tricks to things, removing pistons, etc. Also, there are easy to make 'tools' using long bolts, washers, nuts and all thread rods.

I suggest if attempting to rebuild it yourself. Take many pics along the way. Get familiarized by watching YT vids. Gary Ferraro (channel under his name), for one. & Hiram Gutierrez under Automatic Transmission... both are good friends of mine. Though Hiram no longer makes vids. Purchase the ATSG book as well... they aren't that expensive and a terrific reference & repair manual.

It's a good way to get your feet wet, before you jump in... only you know how mechanically inclined you are. Me? I've been turning wrenches more than half my life. Lol in biz about 25. Don't hesitate to reach out, for sure.
 

Cuba

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These are Hiram's links part 1

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Part 2

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And Gary's link

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Blue Ox

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If you run in to an issue just ask here. We've got some really experienced guys that can get you steered right.

And gals.

Sorry @Cuba for leaving the very capable females on this site out. I'm an unwoke dinosaur, as you can tell by the use of the expression "gals."
 

Rusty Nail

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I wouldn't do it yourself...i'd buy a warranty instead...says the guy on turbo350 NUMBER THREE - in one year. The costs rise quickly.

Did I mention about the warranty?
You might wanna buy one instead of a book, just sayin.
 

Cuba

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And gals.

Sorry @Cuba for leaving the very capable females on this site out. I'm an unwoke dinosaur, as you can tell by the use of the expression "gals."
Hahaha... no worries. No offense taken here! Believe me. It's not many of us in the field and good at it or enjoy it. Heck, and only 10% of technicians continue to go to training once employed. "They know it all and throw parts at things".

I respect your thoughts and commentary throughout this post. Top notch.
 

Cuba

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I wouldn't do it yourself...i'd buy a warranty instead.
I agree with this, because I know builders who have issues. If they are eating the mistakes, even though it costs more upfront due to labor & experience, it's well worth it. Plus, defective parts are more easily replaced under warranty Etc. Then there's the time factor. Most guys have this broken down in an hr or 2 tops, know all that it needs... then back together just as fast after parts arrive. The added bonus of THEM (the builder) test driving & verifying the repair is also well worth it.
 

79dentside

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Good advice all. Really I’m not opposed to a warranty deal... it’s just more money than a self rebuild.


To be honest guys, I wasn’t planning on a trans swap in the dead of winter, I am thinking about trying that long bolt trick, throw another $53 flexplate in and then I can accumulate the trans and do the swap when and where I want. I understand it may break again, I will just try to be easy on it.

On a serious note about the new tranny, I would like to include a shift kit to firm the shifts. Are there stages of aggressive ness? My truck is almost too aggressive, not really sure I want it as harsh. It does not thud into gear, but it rips the tires out from under it when you get on it and I don’t need that at all. I am more looking to increase the life of the clutches with firmer shifts.

Thanks
 

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In your first picture it looks like the flexplate is "bowed" forward ? Like the converter had been pushing on it real hard if it could.

Have you checked to make sure that the crankshaft does not have too much end play ? You really should not be able to move the crankshaft back and forth any noticeable amount. The end play is only about .007" so you might barely feel it move but no more.

When you get it back apart post a picture of the back of the crankshaft.
 

79dentside

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In your first picture it looks like the flexplate is "bowed" forward ? Like the converter had been pushing on it real hard if it could.

Have you checked to make sure that the crankshaft does not have too much end play ? You really should not be able to move the crankshaft back and forth any noticeable amount. The end play is only about .007" so you might barely feel it move but no more.

When you get it back apart post a picture of the back of the crankshaft.
First thing I checked. I have about a 30”steel breaker bar that I pryed back and forth on probably 10 times. Zero visual movement at all. I understand we are talking thousands of an inch for spec, but the converter has probably just shy of 3/4” of movement if the converter is all the way back in the bell housing, not sure that crank end play is my issue. Plausible potential cause though.
 

Cuba

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Good advice all. Really I’m not opposed to a warranty deal... it’s just more money than a self rebuild.


To be honest guys, I wasn’t planning on a trans swap in the dead of winter, I am thinking about trying that long bolt trick, throw another $53 flexplate in and then I can accumulate the trans and do the swap when and where I want. I understand it may break again, I will just try to be easy on it.

On a serious note about the new tranny, I would like to include a shift kit to firm the shifts. Are there stages of aggressive ness? My truck is almost too aggressive, not really sure I want it as harsh. It does not thud into gear, but it rips the tires out from under it when you get on it and I don’t need that at all. I am more looking to increase the life of the clutches with firmer shifts.

Thanks
Yes... shift kits come with a various springs or even drill bits to adjust the shift. In your shoes, just install a simple TransGo kit to prolong life and lubrication. Keep everything else mid range firmness, if anything.

I'll go over that Sk350 kit again to be sure on your specific trans & shift desires though.
 

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