Deck lid misalignment theory!
#1
Deck lid misalignment theory!
We're all familiar with the deck lids on these cars being misaligned and having a bit of an overhang, sometimes a little, sometimes ALOT.
I have a theory as to how this happened. . .
When you order hatch struts for these cars there are multiple options to choose from (spoiler, no spoiler, rear wiper, etc. etc.). My theory is based on the assumption that each different strut option has a different lifting capacity (similar to fiberglass vs steel hood struts).
I would wager that installing any of the stronger hatch struts can cause the struts to slowly "push" the deck lid towards the rear of the car, causing the misalignment/overhang. The decklids would have all been torqued down the same amount whether they had a spoiler, wiper, or whatever so the wildcard factor is what struts were attached. (for anyone who hasn't taken a deck-lid off, the deck lid attaches to the rear glass via elongated holes that allow for forward/back adjustment of the lid. The struts attach directly to the decklid.)
"But some came from the factory like that!" - Yes, and I would also guess that, because it was the 80's, the line workers weren't exactly paying attention to what hatch struts went on which cars. I can imagine someone asking for another box of hatch struts, the new guy saying "There's 3 different ones, which do I get?" and someone telling that person "Ah, it doesn't matter, a strut is a strut!"
That's my theory. Think it carries any weight?
I have a theory as to how this happened. . .
When you order hatch struts for these cars there are multiple options to choose from (spoiler, no spoiler, rear wiper, etc. etc.). My theory is based on the assumption that each different strut option has a different lifting capacity (similar to fiberglass vs steel hood struts).
I would wager that installing any of the stronger hatch struts can cause the struts to slowly "push" the deck lid towards the rear of the car, causing the misalignment/overhang. The decklids would have all been torqued down the same amount whether they had a spoiler, wiper, or whatever so the wildcard factor is what struts were attached. (for anyone who hasn't taken a deck-lid off, the deck lid attaches to the rear glass via elongated holes that allow for forward/back adjustment of the lid. The struts attach directly to the decklid.)
"But some came from the factory like that!" - Yes, and I would also guess that, because it was the 80's, the line workers weren't exactly paying attention to what hatch struts went on which cars. I can imagine someone asking for another box of hatch struts, the new guy saying "There's 3 different ones, which do I get?" and someone telling that person "Ah, it doesn't matter, a strut is a strut!"
That's my theory. Think it carries any weight?
#2
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Re: Deck lid misalignment theory!
We're all familiar with the deck lids on these cars being misaligned and having a bit of an overhang, sometimes a little, sometimes ALOT.
I have a theory as to how this happened. . .
When you order hatch struts for these cars there are multiple options to choose from (spoiler, no spoiler, rear wiper, etc. etc.). My theory is based on the assumption that each different strut option has a different lifting capacity (similar to fiberglass vs steel hood struts).
I would wager that installing any of the stronger hatch struts can cause the struts to slowly "push" the deck lid towards the rear of the car, causing the misalignment/overhang. The decklids would have all been torqued down the same amount whether they had a spoiler, wiper, or whatever so the wildcard factor is what struts were attached. (for anyone who hasn't taken a deck-lid off, the deck lid attaches to the rear glass via elongated holes that allow for forward/back adjustment of the lid. The struts attach directly to the decklid.)
"But some came from the factory like that!" - Yes, and I would also guess that, because it was the 80's, the line workers weren't exactly paying attention to what hatch struts went on which cars. I can imagine someone asking for another box of hatch struts, the new guy saying "There's 3 different ones, which do I get?" and someone telling that person "Ah, it doesn't matter, a strut is a strut!"
That's my theory. Think it carries any weight?
I have a theory as to how this happened. . .
When you order hatch struts for these cars there are multiple options to choose from (spoiler, no spoiler, rear wiper, etc. etc.). My theory is based on the assumption that each different strut option has a different lifting capacity (similar to fiberglass vs steel hood struts).
I would wager that installing any of the stronger hatch struts can cause the struts to slowly "push" the deck lid towards the rear of the car, causing the misalignment/overhang. The decklids would have all been torqued down the same amount whether they had a spoiler, wiper, or whatever so the wildcard factor is what struts were attached. (for anyone who hasn't taken a deck-lid off, the deck lid attaches to the rear glass via elongated holes that allow for forward/back adjustment of the lid. The struts attach directly to the decklid.)
"But some came from the factory like that!" - Yes, and I would also guess that, because it was the 80's, the line workers weren't exactly paying attention to what hatch struts went on which cars. I can imagine someone asking for another box of hatch struts, the new guy saying "There's 3 different ones, which do I get?" and someone telling that person "Ah, it doesn't matter, a strut is a strut!"
That's my theory. Think it carries any weight?
The solution was I replaced my newish strong arm hatch struts rated for spoiler and wiper with AMS4967 rated for no spoiler and wiper from Rockauto and hatch overhang was nearly completely eliminated ( it would be perfect if I pushed in a little past flush as the Factory service manual recommends) but I will call it close enough. As you mentioned the psi ratings for each strut are different and I went with the lowest one I could find.
One thing to note on my car is I have the Hawks fiberglass aerowing spoiler which is much lighter than factory but the those AMS struts work perfect on my car and look great.
#3
On Probation
Re: Deck lid misalignment theory!
NAH...........I still have the weak original OE struts on my 84.
My deck lid is crooked.
Nobody notices it anyhoo.
Unless your one of those "driveway queen naysayers" that is!
So for the extra strong replacement china/mexico junk stretching the lid
from the glass theory dont hold water for me.
NOS replacements are out there and very $pendy.
My deck lid is crooked.
Nobody notices it anyhoo.
Unless your one of those "driveway queen naysayers" that is!
So for the extra strong replacement china/mexico junk stretching the lid
from the glass theory dont hold water for me.
NOS replacements are out there and very $pendy.
#4
Re: Deck lid misalignment theory!
NAH...........I still have the weak original OE struts on my 84.
My deck lid is crooked.
Nobody notices it anyhoo.
Unless your one of those "driveway queen naysayers" that is!
So for the extra strong replacement china/mexico junk stretching the lid
from the glass theory dont hold water for me.
NOS replacements are out there and very $pendy.
My deck lid is crooked.
Nobody notices it anyhoo.
Unless your one of those "driveway queen naysayers" that is!
So for the extra strong replacement china/mexico junk stretching the lid
from the glass theory dont hold water for me.
NOS replacements are out there and very $pendy.
You are of course welcome to disagree.
#5
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Car: 1988 Trans Am GTA
Engine: 5.7 L98
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Axle/Gears: Borg Warner 9 bolt 3.27
Re: Deck lid misalignment theory!
NAH...........I still have the weak original OE struts on my 84.
My deck lid is crooked.
Nobody notices it anyhoo.
Unless your one of those "driveway queen naysayers" that is!
So for the extra strong replacement china/mexico junk stretching the lid
from the glass theory dont hold water for me.
NOS replacements are out there and very $pendy.
My deck lid is crooked.
Nobody notices it anyhoo.
Unless your one of those "driveway queen naysayers" that is!
So for the extra strong replacement china/mexico junk stretching the lid
from the glass theory dont hold water for me.
NOS replacements are out there and very $pendy.
Each car is different but I do agree these things never had perfect panel gaps from the factory so to expect it 30 years later is a big expectation.
#6
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Re: Deck lid misalignment theory!
NAH...........I still have the weak original OE struts on my 84.
My deck lid is crooked.
Nobody notices it anyhoo.
Unless your one of those "driveway queen naysayers" that is!
So for the extra strong replacement china/mexico junk stretching the lid
from the glass theory dont hold water for me.
NOS replacements are out there and very $pendy.
My deck lid is crooked.
Nobody notices it anyhoo.
Unless your one of those "driveway queen naysayers" that is!
So for the extra strong replacement china/mexico junk stretching the lid
from the glass theory dont hold water for me.
NOS replacements are out there and very $pendy.
#7
On Probation
Re: Deck lid misalignment theory!
But the hatch is closed and held in the center by the lock so how would a overstrong
struts stretch the lid crooked on the glass?. Maybe a Friday hatch and glass assembly
job by a lazy employee? Could be many unknown reasons..............
struts stretch the lid crooked on the glass?. Maybe a Friday hatch and glass assembly
job by a lazy employee? Could be many unknown reasons..............
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#8
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Re: Deck lid misalignment theory!
When I tried the weaker pressure struts the alignment improved. Once again this was on my car and each car is different.
#9
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Re: Deck lid misalignment theory!
Once closed with the struts removed the alignment was perfect, when I reinstalled them the alignment was pushed out.
#11
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Re: Deck lid misalignment theory!
the wiggle room is the deck lid itself, not the hinges. it bolts onto the glass thru oval holes in the glass. Maybe 3/4” long? And those allow for the forward/back movement of the deck lid.
#13
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Re: Deck lid misalignment theory!
Anyone got pics of the holes for the decklid?
I wonder if you put some kind of rubber grommet to revent the decklid from moving...
I wonder if you put some kind of rubber grommet to revent the decklid from moving...
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#15
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Re: Deck lid misalignment theory!
check the last 30 seconds of this video and you can kind of see them. also this guy does a really good in depth series on deck lid replacement.
https://youtu.be/iJjJmLOtwm8
https://youtu.be/iJjJmLOtwm8
I'm getting anxiety watching him remove the decklid lol
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#18
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Re: Deck lid misalignment theory!
Yes!
KINDA like how the top hinge bolts that go through the glass.... my worry would be any pressure from the decklid moving or whatever that could crack the glass though...
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#19
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Re: Deck lid misalignment theory!
A very valid concern. Maybe something whittled from a urethane sway bar bushing, or something similar. Firm enough to hold it's shape against the pressure of the struts, elastic enough to bounce back and return to it's original shape if momentarily deformed, and soft enough to absorb impacts and vibrations to save the glass.
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1989karr (06-27-2022)
#20
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Re: Deck lid misalignment theory!
I removed mine completely before I painted the car. I spent an absurd amount of time lining it and the spoiler up before paint. Test fit it after paint had my glass guy seal it and install. Of course it all moved and now looks like I never lined it up!! I may now thing its the struts to cause mine was perfect before I put them back on. I never thought they would cause it. Its gonna stay that way now. Im not risking damaging the paint or breaking the glass to fix it. I searched for a non-defrost back glass when I did it to. I didnt want the defrost lines when I tinted it.
#21
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Re: Deck lid misalignment theory!
I removed mine completely before I painted the car. I spent an absurd amount of time lining it and the spoiler up before paint. Test fit it after paint had my glass guy seal it and install. Of course it all moved and now looks like I never lined it up!! I may now thing its the struts to cause mine was perfect before I put them back on. I never thought they would cause it. Its gonna stay that way now. Im not risking damaging the paint or breaking the glass to fix it. I searched for a non-defrost back glass when I did it to. I didnt want the defrost lines when I tinted it.
What did you use to seal it?
They say you need to let the sealer cure a while before reattaching the struts.
#24
Moderator
Re: Deck lid misalignment theory!
The alignment issue with the hatch is well known on TGO. The hatch struts push back on the deck lid over time and the adhesive used at the factory wasn't strong enough to keep the deck lid from moving. The only fix is to remove the deck lid, clean up the old adhesive, and apply new. Do not use the weaker struts on a car with the spoiler, louvers or rear wiper.
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#25
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Car: 89' Firebird
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Re: Deck lid misalignment theory!
The alignment issue with the hatch is well known on TGO. The hatch struts push back on the deck lid over time and the adhesive used at the factory wasn't strong enough to keep the deck lid from moving. The only fix is to remove the deck lid, clean up the old adhesive, and apply new. Do not use the weaker struts on a car with the spoiler, louvers or rear wiper.
Do you know what type of adhesive is recommended?
I was thinking a thin layer of the stuff professional shops use for windshields.... but that stuff hardens really hard and would seem impossible to remove if need be in the future?
#26
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Re: Deck lid misalignment theory!
The alignment issue with the hatch is well known on TGO. The hatch struts push back on the deck lid over time and the adhesive used at the factory wasn't strong enough to keep the deck lid from moving. The only fix is to remove the deck lid, clean up the old adhesive, and apply new. Do not use the weaker struts on a car with the spoiler, louvers or rear wiper.
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1989karr (07-01-2022)
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#28
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Re: Deck lid misalignment theory!
I had a minor saga dealing with the hatch overhang and after replacing the hinges, attempting to shim the hinges which did nothing (but apparently some cars were shimmed at the factory) taking the decklid off to realign/re-seal all to not fix the problem( however the alignment was perfect with the struts disconnected) but when I reconnected the hatch struts I came to the same conclusion that they are pushing out the decklid.
The solution was I replaced my newish strong arm hatch struts rated for spoiler and wiper with AMS4967 rated for no spoiler and wiper from Rockauto and hatch overhang was nearly completely eliminated ( it would be perfect if I pushed in a little past flush as the Factory service manual recommends) but I will call it close enough. As you mentioned the psi ratings for each strut are different and I went with the lowest one I could find.
One thing to note on my car is I have the Hawks fiberglass aerowing spoiler which is much lighter than factory but the those AMS struts work perfect on my car and look great.
The solution was I replaced my newish strong arm hatch struts rated for spoiler and wiper with AMS4967 rated for no spoiler and wiper from Rockauto and hatch overhang was nearly completely eliminated ( it would be perfect if I pushed in a little past flush as the Factory service manual recommends) but I will call it close enough. As you mentioned the psi ratings for each strut are different and I went with the lowest one I could find.
One thing to note on my car is I have the Hawks fiberglass aerowing spoiler which is much lighter than factory but the those AMS struts work perfect on my car and look great.
Thanks
#29
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Re: Deck lid misalignment theory!
[QUOTE=TABBOO;6475175]I also have the Hawks spoiler and I am interested to know if when using the AMS4967 strut if it is strong enough to hold up the hatch when using the interior hatch release switch so that the hatch doesn't reclose.
Thanks[/QUOTE
I haven’t really experimented much with that as I don’t open the hatch a lot but the struts have no trouble holding the hatch up when it’s opened.
Thanks[/QUOTE
I haven’t really experimented much with that as I don’t open the hatch a lot but the struts have no trouble holding the hatch up when it’s opened.
#30
Re: Deck lid misalignment theory!
I'm glad I found this thread because I have about 1/4" of overhang on my rear hatch, but it's worse on the right than the left side. It looks like the whole hatch (and not just the decklid) on mine is pushed back because there is a HUGE gap between the car top and the top of the hatch, especially on the right side. I'm thinking there must be something wrong with that hinge; either the pin is worn out or the hinge got bent somehow. Am I on the right track?
#31
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Re: Deck lid misalignment theory!
I'm glad I found this thread because I have about 1/4" of overhang on my rear hatch, but it's worse on the right than the left side. It looks like the whole hatch (and not just the decklid) on mine is pushed back because there is a HUGE gap between the car top and the top of the hatch, especially on the right side. I'm thinking there must be something wrong with that hinge; either the pin is worn out or the hinge got bent somehow. Am I on the right track?
Also if you recently changed trunk hatch struts that can cause the lid to push out too.
#32
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Re: Deck lid misalignment theory!
It looks like the whole hatch (and not just the decklid) on mine is pushed back because there is a HUGE gap between the car top and the top of the hatch, especially on the right side.
#33
Re: Deck lid misalignment theory!
I have the hatch to roof hinge adjusted as far forward as it will go but still have a 1/2" or so gap there, so something must be really wrong. I thought I would take the right strut off and see if I can push the right side forward and backward to find out if there is play in the hinge. I wish it would be as simple as making the adjustments at the bottom of the glass as in the video, but it seems like there is something different that is the (main) problem in my case.
Did GM just use one model rear hatch assembly (including the hinges) for the entire 3rd gen. f-body run? There is evidence of two large stripes being on my decklid, but I can't find evidence of stripes on the hood, like the rear hatch might have been replaced at some point. I was wondering if this might have something to do with my problem, although the gaps on the left side of the hatch seem to be better, which makes me think it might not be this that is making any difference in how it mounts.
Did GM just use one model rear hatch assembly (including the hinges) for the entire 3rd gen. f-body run? There is evidence of two large stripes being on my decklid, but I can't find evidence of stripes on the hood, like the rear hatch might have been replaced at some point. I was wondering if this might have something to do with my problem, although the gaps on the left side of the hatch seem to be better, which makes me think it might not be this that is making any difference in how it mounts.
#34
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Re: Deck lid misalignment theory!
I would suggest that if the glass itself is physically mis-aligned to the car, meaning larger gap on ONE side than the other, it would HAVE to be a hinge issue. If I may make a suggestion about board etiquette, why don't you start a specific thread. Since it appears your issue isn't the typical misaligned hatch problem, you'll likely get more traction with a new thread. ...that being said though, I don't see how it's NOT the hinges, at least in your case.
#35
Re: Deck lid misalignment theory!
I would suggest that if the glass itself is physically mis-aligned to the car, meaning larger gap on ONE side than the other, it would HAVE to be a hinge issue. If I may make a suggestion about board etiquette, why don't you start a specific thread. Since it appears your issue isn't the typical misaligned hatch problem, you'll likely get more traction with a new thread. ...that being said though, I don't see how it's NOT the hinges, at least in your case.
#36
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Re: Deck lid misalignment theory!
I considered starting a new thread, but thought what I have going one was relevant to this thread. I certainly wasn't trying to hijack this one. I'll go ahead and start a new thread when I know more about what I think the problem is.
#38
Re: Deck lid misalignment theory!
too strong a strut will push the deck lid back in the elongated holes causing misalignment.
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Bob88GTA (12-10-2022)
#39
Junior Member
Re: Deck lid misalignment theory!
I know I am late to the party but I just replaced my struts. Before replacement my alignment was perfect. After I have the alignment issue and came to the same conclusion as the original poster. Then I saw this tread.
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RedLeader289 (12-10-2022)
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