It seems that hard-top 3rd gens are prone to stress cracks in where the roof and quarter panel meet. It's a poor design because of the right angle there, which causes a high stress concentration. I am planning to put on a set of subframe connectors to minimize the body flex, but how do I take care of these cracks? My only thought is to hammer a small divit where the crack is, weld it, and grind it down, fill, etc. Has anyone tackled this any other way and been successful?

89 Transam GTA, a few bolt ons

 

That's the only way to do it, with one addition. Before you weld it, drill a small hole at the end of the crack.

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Kenney
82 Trans Am WS7 notchback
83 Trans Am WS6 T-tops
72 Vista Cruiser 455
90 Olds Trofeo
80 K-10 w/snow plow
Painter @ Chevy dealer
GM junkie

 

I was planning to drill the hole, but forgot to mention it. Thanks for the help.

 

yah, my car has those things too, on both sides of the car, gotta get em fixed. How much would it be to have it filled/sanded/painted do you think?

 

T-Top cars get em too.
My 83 Trans-am with the 305 CFI t-top got em
My 90 Formula 350 TPI t-top has em too.

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84 FIREBIRD-(undergoing rebuild)2.8 V6,5spd,T-Top
90 Formula Modded 350 TPI T-Top
WANTED:82-84 Firebird 2.5 4cyl,4spd-Just Cause

Previous 3rd gen's
83 Trans-Am 305 CFI auto T-TOP
84 Firebird 305 H.O. auto HARDTOP
87 Firebird 2.8 V-6 auto HARDTOP

 

if I remember right that's been a problem since the El Camino's, but GM never really took car of it until fourthgens

 

i have what looks to b a very small stess crack on the passenger side. i have a t-top car. i also have subfram conectors, but they r boted on. i am going to get them welded. im worryied about the crack tho. if its a little one how seriously is my fram twisted?

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89' Firebird Formula WS6 L98, MSD 6AL MSD Blaster, Hypertech chip, K/N filter cone,flowmaster 80 series, hypertech air foil, koni shocks, edelbrock trailing arms

 

My previous car was an 86 IROC. It has the cracks, but they never really got bad. I drove the car for 2 years, and I'm pretty sure they were there the whole time. The car also had Edelbrock springs and Koni shocks, and no subframe connectors. Talk about creaks and rattles. I could feel the car flex as I pulled into drivways. I don't think they're too much of an emergency to take care of, since mine didn't change much in 2 years, but fixing the cause is always a good idea.

As for how much to fix? probably pretty expensive. An hour or two of bodywork, and a lot of paint blending in the roof and the quarter. I'd guess at least $500.


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89 Transam GTA, 350TPI, auto, 3.27 rear, dual cats, gray.
Magnaflow cat-back,
K&N open element,
Best E.T. 14.63@95mph

 

Mine has those too, its an 83, only has it on the passenger side and this car had been beat to hell before I got ahold of it lol... I when I get mine fixed I'm thinking of getting something inside to add a bit more support on each side... anyone ever thought of doing that? I'm getting the entire thing repainted when I get done with the body work so its not like thats really gonna be a pain in the *** when I do it hehe

 

Does anyone know if stress cracks are a problem on v6 cars, or do they put out too little power to cause any harm?

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86 Sport Coupe, 2.8 V6, dead stock, but not for long!

Daily driver:
2000 Pontiac Grand Am SE2

"Little girls play with ponies!"
www.geocities.com/camman86

 

I think its more of flexing from a stiff suspension and a weak body, not the power of the engine. Most V6's has a softer suspension, so they probably had fewer problems, but i know of some with cracks.

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89 Transam GTA, 350TPI, auto, 3.27 rear, dual cats, gray.
Magnaflow cat-back,
K&N open element,
Best E.T. 14.63@95mph

 

My '86 V6 has the stress cracks, also.

Filler won't fix it, either... I tried. In fact, GM fills that area with lead, so when you're sanding it down, use a dust mask- I didn't. I found out about the lead later... I thought it was some odd Bondo put there by the previous owner.

Anyway, I tried fixing both sides with filler; it was fine until the car sat in the hot sun- then the filler cracked. Driving also cracked it. The only true fix is to have the cracks welded shut.


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-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

 

So what can be done to pevent them?

 

Welding in subframe connectors would probably help a great deal, since the car would twist less, but don't hold me to that! The cracks might show up anyway.

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-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

 

had an 84 Z28 HO305 that i cracked windshield and the top on it.
windshield cracked vertically near center, it was fun car

im worrying about the 82 T/A, i havent really looked hard to see if it has any cracking on the top, but im sure it does, or will have them anyways with the 350 thats going in it currently

if it cracks then it cracks- if not then ok, doesnt matter too much really.

 

i have had two t-top 350 tpi thirdgens and a hard top 350 tpi thirdgen i havent seem these kinda cracks yet, but i am glad i got sfc's on my 91. flex is one thing, cracks are another. i would guess a roll bar would help even more to prevent these cracks also.

 

ANOTHER thing I would suggest for any of you Hard top guys is to go to the junk yard and pick up some of the little Door jam wedges for T-top cars. This will help transfer the load... SFC's are the BEST idea.

John

 

yes... v6's get them too. mine popped up after owning my car for about 6 months. as for welding material behind to help stiffen things up, it occured to me, but when i took my headliner off to recover it i noticed that there is no way possible to see the affected area unless you remove the pillars along the roof, which would defeat the point

 

[QUOTE=TomP;401712]My '86 V6 has the stress cracks, also.

Filler won't fix it, either... I tried. In fact, GM fills that area with lead, so when you're sanding it down, use a dust mask- I didn't. I found out about the lead later... I thought it was some odd Bondo put there by the previous owner.QUOTE]

I was wondering what that was to when I was sanding I wish I would have know that was lead lol when I had my old car well I guess its to late now a little lead never hurt anyone

 

Major bump, but does anyone have any pics of the said wedges?

 

Here:

https://www.thirdgen.org/forums/conv...forcement.html

https://www.thirdgen.org/forums/atta...ighlighted.jpg

John

 

I need to get me some of these I always wondered what they were for on my t-top RS

 

If you pick them up in a junkyard they might even give them to you... Go around to a couple of cars and pick up more than one set. They use a sheet metal shim for gap spacing not all cars are the same, get some extra shims. Basically there are the following parts:

4 Screws
Door wedge
Body Wedge
Shims
2 Rubber pieces that go under both the Door Wedge and Body Wedge.

John

 

[QUOTE=okfoz;3590784]If you pick them up in a junkyard they might even give them to you... Go around to a couple of cars and pick up more than one set. They use a sheet metal shim for gap spacing not all cars are the same, get some extra shims. Basically there are the following parts:

4 Screws
Door wedge
Body Wedge
Shims
2 Rubber pieces that go under both the Door Wedge and Body Wedge.

for some reason my roof has no cracks but a bulge or a noticeable feel right on the drip rail. On the b pillar where it starts to slope down. Where the window is parallel to the roof that’s where it feels different it isn’t a slope it’s almost warped is this something I should be worried about? What can I do to fix it? Again there are no stress cracks anywhere on the car and this concerns me

 

[QUOTE=Formy_WS9_89;6422260]


Maybe a rust bubble starting to form?

 

[QUOTE=1989karr;6422311]I highly doubt it. It’s extremely clean except for that crease or bulge. I’m not sure if it’s the seam or a body line or actual damage

 

[QUOTE=Formy_WS9_89;6422260]Take a picture.
There is a Factory Lead line from the top of the doors to the rear window where they joined the roof panel to the rear quarter panels.