The 1968 Buick Riviera came at a time when personal luxury cars were blending dramatic styling with substantial road presence, and the Riviera stood apart with a distinctly tailored Buick character. Owners today often approach one as both a driver and a preservation piece, which makes tire choice especially important. The 1968 Buick Riviera uses an 8.45-15 bias-ply tire on a 15-inch rim, keeping the fitment rooted in the period sizing and construction style the car was built around. That puts the focus on selecting the right period-style presentation and construction approach for the way the car will be used. For restoration-minded owners, appearance, wheel compatibility, and overall stance all deserve a careful look before changing anything.
Which Tire Size Is Right for The 1968 Buick Riviera
The 1968 Buick Riviera uses one primary tire size: 8.45-15. It is a bias-ply fitment for a 15-inch rim, and the covered Riviera sub-model shares that same sizing. That means the main decision is not which size fits, but which 8.45-15 tire best matches your goals for appearance, construction style, and the way the car will be driven and maintained.
An 8.45-15 tire uses a vintage numeric bias-ply size system, where 8.45 refers to the nominal section width in inches and 15 identifies the wheel diameter. On a 1968 Buick Riviera, this size keeps the car in its proper period-style fitment category and preserves the traditional bias-ply construction that suits many restoration-oriented setups. Buyers looking at this size typically focus on how the tire complements the Riviera’s stance, sidewall appearance, and intended use as either a show car or an occasional road car. The right choice starts with the correct 15-inch wheel and a clear idea of whether maintaining original-type construction is part of the plan.
Tire fitment is straightforward for the covered 1968 Buick Riviera sub-model. The shared sizing keeps the focus on selecting the right 8.45-15 tire for the car’s appearance, wheel setup, and intended road use rather than sorting through multiple factory size combinations.
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1968 Buick Riviera Base
The 1968 Buick Riviera Base uses the same 8.45-15 bias-ply fitment that defines this page. For the buyer, that makes tire selection more about staying true to the car’s traditional sizing and confirming the 15-inch wheel setup than comparing multiple primary fitment sizes.
The tire sizes listed on this page assume factory-standard vehicle configuration. The following modifications may affect tire fitment and are not reflected in this guide:
Suspension changes (lowering, lift kits, spring replacements)
Body alterations (fender modifications, custom bodywork)
If your vehicle has been modified from factory specifications, verify tire clearance before purchase.
Frequently Asked Questions
Owners of a 1968 Buick Riviera usually want clear answers on 8.45-15 sizing, 15-inch rim fitment, bias-ply construction, restoration appearance, and the wheel and suspension checks worth making before regular road use.
Tire Size & Fitment
What tire size fits a 1968 Buick Riviera?
The 1968 Buick Riviera uses an 8.45-15 tire size. This is a vintage numeric bias-ply fitment, so the size follows an older sizing convention rather than a modern metric radial format.
That makes the first step fairly simple: confirm that the car still has the proper 15-inch wheels and that no previous owner changed the wheel or suspension setup. Once size is confirmed, the real decision becomes choosing an 8.45-15 tire that suits the Riviera’s intended use, visual style, and restoration goals.
What size rim does a 1968 Buick Riviera use?
The tire fitment for the 1968 Buick Riviera is built around a 15-inch rim diameter. The 8.45-15 size uses that 15-inch wheel diameter as the foundation for proper mounting.
Rim diameter should always be verified on the car itself, especially if the Riviera has seen wheel changes over the years. A matching diameter alone is not the only consideration, so wheel width, condition, and overall compatibility with the selected tire should also be checked before mounting a new set.
Does the 1968 Buick Riviera Base use the same tire size?
Yes. The 1968 Buick Riviera Base uses the same 8.45-15 bias-ply tire size as the core Riviera fitment shown here. There is no separate primary size to sort through for that covered sub-model.
That consistency simplifies the buying process because the question is not about choosing between multiple factory sizes. Instead, attention can shift to selecting the right tire within the 8.45-15 category and confirming that the car still retains a wheel and suspension setup compatible with traditional bias-ply fitment.
Choosing the Right Tire
What should I consider when choosing a 8.45-15 tire for a 1968 Buick Riviera?
Start with the basics: the tire should be the correct 8.45-15 size and suited to a 15-inch wheel. Since this Riviera fitment is bias-ply, many owners also consider whether they want to preserve the car’s traditional construction type and period-style look.
After that, think about how the car will actually be used. A Riviera headed to shows may call for a different presentation than one that sees occasional weekend road miles, so wheel condition, overall stance, tire appearance, and the car’s current setup should all be weighed before making a final selection.
How do I choose between available 8.45-15 tires for a 1968 Buick Riviera?
The right choice depends on the kind of Riviera you are maintaining. With one primary size, the comparison usually centers on traditional appearance, construction style, and how closely the tire suits the character of a late-1960s personal luxury car.
A careful buyer should also compare wheel compatibility and the condition of the car’s suspension and steering components before settling on a tire. Even when the size is correct, an older vehicle can respond differently depending on alignment condition, ride-height changes, and how closely the rest of the chassis remains to stock.
What does 8.45-15 mean on a 1968 Buick Riviera?
The 8.45-15 designation is a vintage numeric bias-ply size. In this format, 8.45 refers to the tire’s nominal section width in inches, while 15 identifies the wheel diameter the tire is meant to fit.
That matters because the size does not read like a modern metric radial marking, and it should not be interpreted the same way as a P-metric tire. Understanding the older format helps you stay focused on proper period-style fitment and avoid choosing a tire simply because its markings look familiar by modern standards.
Restoration & Appearance
Which tire should I choose for a period-style 1968 Buick Riviera?
For a period-style 1968 Buick Riviera, the natural starting point is the original-type 8.45-15 bias-ply sizing and 15-inch rim fitment. That keeps the car aligned with the sizing system and construction style associated with its era.
Appearance matters on a Riviera because the tire has a visible effect on stance and overall presentation. Owners pursuing a highly exact restoration should also compare their choice against marque-specific references and vehicle history, since period-style fitment is a strong foundation but not the same thing as proving exact factory delivery details.
Does correct tire fitment matter for a 1968 Buick Riviera restoration?
Yes, correct tire fitment matters on a 1968 Buick Riviera restoration because tire size and construction affect both the car’s appearance and how authentically it presents. The 8.45-15 bias-ply format supports the traditional visual balance expected on a car from this period.
Using the right size also helps preserve the relationship between wheel opening, sidewall profile, and overall stance. Even on a driver-quality restoration, it is worth confirming that the wheels match the intended tire and that past modifications have not changed the way the car sits or clears the tires at full steering travel.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 1968 Buick Riviera?
Yes. Modifications can change tire fitment on a 1968 Buick Riviera even when the intended size remains 8.45-15. Aftermarket wheels, altered ride height, suspension work, or body changes can all affect how much space the tire has and how it sits on the car.
A Riviera that has been lowered, fitted with different wheels, or repaired with non-original parts deserves a careful check before new tires go on. Wheel diameter is only one part of the equation, so steering clearance, fender clearance, and the actual wheel dimensions should all be confirmed on the car itself.
What should I inspect before driving a 1968 Buick Riviera on new tires?
Before putting a 1968 Buick Riviera back on the road with new tires, inspect the wheels, valve stems, lug hardware, and the overall condition of the suspension and steering system. Tire pressure should also be set correctly, and the tires themselves should be checked for any mounting or seating concerns.
An older car that has spent long periods parked can have issues that a fresh set of tires will not solve by itself. It is smart to look over alignment, brake condition, signs of rubbing, and any aged chassis components so the new tires are not being asked to compensate for unrelated mechanical problems.
How should 8.45-15 tires on a collector 1968 Buick Riviera be maintained?
Collector-car tires should be inspected regularly even if the 1968 Buick Riviera is driven only occasionally. Pay attention to air pressure, visible cracking, tread condition, bulges, cuts, and any signs that the car has been sitting long enough to affect the tires’ shape or behavior.
Storage habits matter just as much as mileage on a collector vehicle. Keeping the Riviera away from prolonged sunlight, excess heat, moisture, and ozone sources can help protect the tires, and periodic checks before each drive are a sensible habit because age and storage can matter as much as road wear.
