If you were standing in a Buick dealership back in 1987, you had a choice that would haunt your resale value for the next four decades. You could stick with the rigid, "boring" hardtop, or you could tick the box for the Grand National T top configuration. It seemed like a no-brainer at the time. Who wouldn't want to feel the wind hitting their face while that Garrett AiResearch turbocharger whistled like a tea kettle from hell? It was the peak of 80s cool. It turned a sinister, Darth Vader-esque coupe into something you could actually enjoy on a coastal drive.
But man, things got complicated fast.
The Buick Grand National wasn't just a car; it was a middle finger from the engineers at Flint to the rest of the performance world. It shouldn't have worked. A 3.8-liter V6 pushing out enough torque to embarrass a V8? In a chassis that was basically a glorified grandmother's Regal? It was glorious. Yet, when you cut two massive holes in the roof of a G-Body frame, you change the physics of the machine. Honestly, it’s kind of a miracle these cars didn't just fold in half the first time someone launched them on sticky tires.
The Reality of G-Body Flex and the T-Top Trade-off
You’ve gotta understand how these cars were built. The GM G-Body platform was a body-on-frame design. It’s tough, sure, but it isn’t exactly a paragon of torsional rigidity. When you have a Grand National T top, you’re removing a significant chunk of the structural integrity provided by the roof skin and the B-pillar bracing.
People think the "T-bar" in the middle does a lot of work. It doesn't.
It's mostly there to hold the glass. When you're pushing 15+ psi of boost and that torque hits the rear wheels, the whole car wants to twist. Hardtop owners usually just deal with a bit of body roll. T-top owners? They get to hear the seals squeaking, the glass rattling, and in extreme cases, they might even see the dreaded "A-pillar crack." This is a real thing that haunts the Buick community. If you see a Grand National with a tiny hairline fracture in the paint at the base of the A-pillar or the corner of the T-top opening, you know that car has spent its life at the drag strip.
It’s a trade-off. You get the open-air experience, which is undeniably rad, but you lose that rock-solid feeling of a closed cockpit. Does it matter if you're just cruising to a Saturday morning Cars and Coffee? Probably not. Does it matter if you’re trying to run 10s in the quarter-mile? Absolutely.
👉 See also: Sleeping With Your Neighbor: Why It Is More Complicated Than You Think
The Leak Factor: It’s Not If, It’s When
Let’s talk about the Fisher T-tops. These weren't the Hurst hatches found on earlier GM models; by the mid-80s, Buick was using the factory Fisher setup. They look better and they’re generally more reliable, but "reliable" is a relative term when talking about 1980s GM weatherstripping.
If you own a Grand National T top, you are basically a part-time amateur hydrologist.
The seals are complex. They have multiple channels designed to divert water away from the interior, but after thirty or forty years, that rubber turns into something resembling dry beef jerky. Once the seal loses its suppleness, the water finds a way in. It usually starts as a drip on your left knee during a heavy downpour. Then it migrates to the floorboards.
- The Problem: Water gets trapped under the thick factory carpeting and the sound deadening.
- The Result: The floorpans start to rot from the inside out, often hidden from view until you pull the seats.
- The Fix: You’ve basically got to spend $500 to $800 on a high-quality weatherstripping kit from a specialist like Highway Stars or Kirban Performance.
Installation is a nightmare, too. You can't just slap the rubber on. You have to adjust the "blow-out" clips and ensure the glass sits at the exact right angle. It’s a game of millimeters. Most guys end up using a bucket of soapy water and a shop vac just to find where the air whistles are coming from at 70 mph.
Performance vs. Aesthetics: The Great Debate
There is a weird hierarchy in the Buick world. The hardtop cars are almost always worth more to the "purists" and the racers. Why? Because they’re lighter and stiffer. A hardtop 1987 GN is the ultimate "tuner" starting point. It’s the "WE4" or the lightweight option that people hunt for.
But wait.
✨ Don't miss: At Home French Manicure: Why Yours Looks Cheap and How to Fix It
The Grand National T top has a different kind of gravity. When you see a GN with the tops off, showing off that grey and black interior, it looks like a million bucks. It softens the "brick" aerodynamics of the Regal body style. It makes the car feel more like a grand tourer and less like a getaway car for a bank heist.
I’ve talked to guys who have owned both. The consensus is usually this: if you want a car to keep forever and take to shows, get the T-tops. If you want a car to modify until the turbo is the size of a watermelon, get the hardtop.
There’s also the "S-body" reinforcement issue. GNX models (the legendary 547-unit run) were almost all hardtops. In fact, only a tiny handful of T-top GNXs were ever rumored to exist, and even then, McLaren Engines (who did the GNX conversion) had to add significant bracing to the rear to keep the frame from twisting under the power of that upgraded ceramic turbine. That should tell you everything you need to know about the factory's opinion on roof holes and high horsepower.
Buying a Grand National T-Top: What to Look For
If you’re in the market, you can't just check the oil and kick the tires. You need to be a detective.
First, check the trunk. Not for bodies—though it’s big enough—but for the original T-top storage bags. They’re made of a specific vinyl material and they’re often missing. Replacing them with authentic versions isn't cheap.
Second, look at the "rim" of the T-top opening. Take the glass out. Look for bubbling paint. Because water sits in those channels, rust can start in the metal lip that holds the weatherstripping. If that lip is gone, you’re looking at a massive bodywork bill involving cutting and welding. It’s the stuff of nightmares.
🔗 Read more: Popeyes Louisiana Kitchen Menu: Why You’re Probably Ordering Wrong
Third, check the RPO codes. You’re looking for "CC1" on the underside of the trunk lid. That’s the factory code for the T-top roof. If a car has T-tops but doesn't have that code, someone took a Sawzall to a hardtop car. Run away. Fast.
Maintenance is a Lifestyle
Owning a Grand National T top means you're now a hobbyist in rubber maintenance. You’ll become intimately familiar with Krytox or Honda Shin-Etsu grease. These are specialized lubricants that keep the rubber from sticking to the glass and prevent that "creaking" sound when you go over a driveway apron.
Honestly, it’s a labor of love. There is something uniquely 1987 about reaching up, flicking the heavy chrome handle, and lifting out a slab of tinted glass. It’s tactile. It’s mechanical. It feels like you’re prepping a fighter jet for takeoff.
Does it make the car slower? Technically, yes, due to the extra weight of the glass and the reinforcements. Does it make it leak? Probably. But when you’re cruising down a backroad with the V6 humming and the wind swirling through the cabin, none of that matters. You’re in one of the baddest cars ever to come out of Detroit.
Actionable Steps for Owners and Buyers
If you’re serious about the T-top life, don't just wing it.
- Verify the Frame: Before buying, put the car on a lift. Look for any signs of frame repair or wrinkling in the rear quarters. This indicates the car was launched hard without proper "missing link" braces or aftermarket suspension.
- Seal Maintenance: If you already own one, don't use Armor All on your seals. It contains silicone that can actually dry out some types of rubber over time. Use a dedicated weatherstrip conditioner.
- Storage Matters: Never leave your T-tops lying on the garage floor. They shatter easily and the trim pieces are getting harder to find. Always use the bags and secure them in the trunk brackets.
- Brace Yourself: If you plan on adding more boost (which, let’s be honest, you will), invest in a set of "K-braces" and "Rear Seat Braces." These are simple metal bars that bolt into the chassis and trunk area. They significantly reduce the "G-Body shuffle" and keep your T-top opening from twisting out of alignment.
- Check the Drain Holes: There are tiny tubes designed to let water escape the T-top channels. If these get clogged with pine needles or dirt, water will back up and dump into your lap the first time you take a hard left turn. Run a piece of weed-whacker line through them to keep them clear.
The Buick Grand National is a legend, regardless of the roof. But the T-top version represents a specific era of automotive excess. It’s flawed, it’s noisy, and it’s a bit temperamental—but that’s exactly why we love it. You aren't just buying a car; you're adopting a piece of 80s engineering that demands your attention. Give it that attention, and it’ll give you the coolest ride on the road.