The 1968 Cadillac Commercial Series came from an era when Cadillac chassis underpinned professional and specialty coachbuilt vehicles built for long service, substantial weight, and unmistakable presence. Buyers approaching one today are usually balancing roadworthiness, proper stance, and a presentation that suits a hearse, ambulance, or other commercial-bodied Cadillac of the period. This application uses a 890-15 bias-ply tire on a 15-inch rim, keeping the fitment firmly in traditional full-size American tire territory. Available choices include blackwall and wide whitewall presentations from Firestone and Avon. For restoration-minded use, the key is choosing the right appearance while confirming wheel condition and load suitability before putting the vehicle back into service.
Which Tire Size Is Right for The 1968 Cadillac Commercial Series
The 1968 Cadillac Commercial Series uses one primary tire size: 890-15. It is a bias-ply fitment built for a 15-inch rim, and the same size carries across the covered Commercial Series application here, including the Base sub-model. That means the main decision is not which primary size fits, but which 890-15 tire best matches the vehicle’s appearance, intended use, and wheel setup.
An 890-15 is a vintage numeric bias-ply size where the leading number represents the tire’s nominal section width in inches, while the final number identifies the 15-inch rim diameter. Its bias-ply construction matches the traditional fitment style associated with a late-1960s Cadillac Commercial Series and preserves the tall, substantial look these large professional cars and specialty vehicles typically carry. In this size, choices include Firestone Classic Bias Ply wide whitewall versions and an Avon Turbospeed Mk4 blackwall. Selecting among them comes down to the visual character you want and whether the wheel and vehicle setup suit the tire’s intended load and service role.
Tire fitment is straightforward for the covered 1968 Cadillac Commercial Series sub-models. The Base application uses the same primary size, so the focus stays on choosing the right 890-15 tire style and confirming the vehicle’s actual wheel setup.
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1968 Cadillac Commercial Series Base
The 1968 Cadillac Commercial Series Base uses the 890-15 bias-ply tire size on a 15-inch rim. That keeps selection centered on whether a blackwall or wide whitewall better suits the vehicle’s presentation, along with checking wheel condition and service readiness before road use.
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.
Best 1968 Cadillac Commercial Series Tires for Sale
Available 890-15 choices include Firestone and Avon offerings in different visual styles. Buyers can compare Firestone Classic Bias Ply wide whitewalls and the Avon Turbospeed Mk4 blackwall, along with rim-width compatibility and load-related specifications where shown.
Owners of a 1968 Cadillac Commercial Series usually need clear answers on 890-15 fitment, 15-inch rim use, bias-ply construction, sidewall appearance, and what to inspect before returning a large collector vehicle to the road.
Tire Size & Fitment
What tire size fits a 1968 Cadillac Commercial Series?
The 1968 Cadillac Commercial Series uses a 890-15 tire size. This is a numeric bias-ply fitment used on a 15-inch rim, and it is the primary size associated with the covered Commercial Series application, including the Base sub-model.
That makes the first job fairly simple: confirm that the vehicle still has the correct 15-inch wheels and has not been altered with later rims or suspension changes. Once that is established, the choice becomes more about sidewall appearance, tire series, and service suitability than about sorting through multiple original tire sizes.
What size rim does a 1968 Cadillac Commercial Series use?
The primary tire fitment for a 1968 Cadillac Commercial Series is built around a 15-inch rim. The 890-15 size itself points to that rim diameter, and available products in this fitment are also built for 15-inch wheel use.
Rim diameter is only part of the check on a large coachbuilt Cadillac. Wheel condition, actual rim width, and whether the vehicle still carries its proper wheels matter before mounting new tires. That is especially important on commercial-bodied vehicles, where years of service, storage, or modification can leave the actual wheel setup different from what the tire size suggests.
Does the 1968 Cadillac Commercial Series Base use the same tire size?
Yes. The 1968 Cadillac Commercial Series Base uses the same 890-15 bias-ply tire size as the covered Commercial Series application. There is no separate primary tire size here for the Base model within this fitment grouping.
That consistency simplifies shopping, but it does not remove the need to inspect the vehicle itself. Professional and specialty Cadillacs can have long service histories, so it is worth confirming the wheels on the car, checking for body or suspension changes, and choosing the tire style that fits the vehicle’s intended restoration or road-use presentation.
Choosing the Right Tire
What should I consider when choosing a 890-15 tire for a 1968 Cadillac Commercial Series?
Start with the basics: the 1968 Cadillac Commercial Series uses a 890-15 bias-ply tire on a 15-inch rim. After confirming that size and construction, compare the available options by sidewall style, tire series, and any load-related details that matter for a large commercial-bodied Cadillac.
A wide whitewall can create a more formal period-style presentation, while a blackwall gives a more restrained look. It also helps to verify actual wheel width and overall wheel condition before making a final choice, since appearance alone should not outweigh fitment, service demands, or the vehicle’s real-world use.
What sidewall styles are available for 1968 Cadillac Commercial Series tires?
The available 890-15 tires for a 1968 Cadillac Commercial Series include both wide whitewall and blackwall styles. Firestone offers wide whitewall versions in this size, while Avon offers a blackwall option through the Turbospeed Mk4 line.
That gives the owner a meaningful appearance choice without changing the primary tire size. Whitewalls usually suit a more formal restoration-oriented presentation, while blackwalls can make sense for a more understated look. The right decision depends on how the vehicle is being presented and whether the rest of the wheel-and-trim combination supports that visual direction.
What brands offer tires for the 1968 Cadillac Commercial Series?
Firestone and Avon both offer tires in the 890-15 size for the 1968 Cadillac Commercial Series. Firestone appears here in the Classic Bias Ply series, while Avon is represented by the Turbospeed Mk4, giving buyers more than one traditional bias-ply path in the correct primary size.
Brand choice should be considered alongside sidewall style, tire series character, and wheel compatibility rather than treated as a ranking exercise. A buyer choosing between Firestone and Avon should also think about whether the goal is a wide-whitewall presentation or a blackwall look, since that visual decision may narrow the field quickly.
Restoration & Appearance
Which tire should I choose for a period-style 1968 Cadillac Commercial Series?
A period-style approach starts with the correct primary size and construction, which for the 1968 Cadillac Commercial Series is 890-15 in a bias-ply design. From there, the most visible choice is sidewall treatment, with wide whitewall and blackwall options offering two distinctly different presentations.
For many restoration-minded owners, the tire should support the body style, trim level, and intended visual era of the vehicle rather than simply fill the wheel opening. If exact historical authenticity matters, compare the tire choice against marque references, coachbuilder history, and surviving vehicle examples before settling on one sidewall style.
How does tire construction affect the appearance of a restored 1968 Cadillac Commercial Series?
The 1968 Cadillac Commercial Series uses a bias-ply tire fitment, and that construction plays a large part in the vehicle’s visual character. A 890-15 bias-ply helps maintain the traditional profile and stance expected on a large late-1960s Cadillac commercial chassis.
Appearance is not just about width or whitewall treatment; the construction itself influences how authentic and era-appropriate the overall presentation feels. On a restoration-oriented vehicle, keeping the bias-ply format usually preserves the intended visual impression more naturally, especially when paired with a sidewall style that suits the body and trim.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 1968 Cadillac Commercial Series?
Yes. Even though the 1968 Cadillac Commercial Series uses a 890-15 tire on a 15-inch rim, modifications can still affect how that fitment works in practice. Aftermarket wheels, suspension changes, altered ride height, or bodywork repairs can all change clearance and wheel compatibility.
A commercial-bodied Cadillac deserves an especially careful check because these vehicles often lived long working lives before becoming collectibles. Looking at wheel width, steering clearance, fender space, and general suspension condition before mounting new tires can prevent fitment surprises and help the vehicle sit and drive as expected.
What should I inspect before driving a 1968 Cadillac Commercial Series on new tires?
Before putting a 1968 Cadillac Commercial Series back on the road, inspect the wheels for damage or corrosion and make sure the 15-inch rims are appropriate for the 890-15 tire. It is also wise to check suspension wear, steering components, and brake condition on a vehicle of this size and age.
Tires should then be examined regularly for proper inflation, air loss, cuts, bulges, and any signs of uneven wear after installation. Since collector and specialty vehicles may sit for long periods, a careful pre-drive inspection matters just as much as the initial mounting, especially before carrying passengers or taking a longer trip.
How should 890-15 tires on a collector 1968 Cadillac Commercial Series be maintained?
Maintain 890-15 tires on a collector 1968 Cadillac Commercial Series by checking air pressure regularly, watching for visible aging or cracking, and inspecting the tread and sidewalls even when the vehicle is driven only occasionally. Collector mileage can be low while tire aging still progresses over time.
Storage conditions matter almost as much as road use on a vehicle like this. Keeping the Cadillac away from prolonged sunlight, moisture, and ozone sources helps protect the tires, and moving or driving the vehicle periodically can help avoid long-term flat spotting. Frequent visual inspection is especially important on older specialty vehicles.
