Here's why:
* Trim Level Variations: Different trim levels of the 1991 Suburban may have slightly different fender well clearances.
* Existing Tire Size: The current tire size significantly impacts what size you can safely and comfortably upgrade to. Larger tires often mean more rubbing.
* Backspacing/Offset: The wheel's backspacing and offset will influence how far the tire sits in or out of the wheel well. A wheel with less backspacing will push the tire further out, increasing the likelihood of rubbing.
* Suspension Components: The condition of your suspension components also plays a role. Worn components might reduce available clearance.
General Guidance (with significant caveats):
Most people report that going more than one size larger than the stock tire size on a 1991 Suburban without a lift kit will likely result in rubbing, especially during turning and suspension articulation. You might be able to squeeze in a slightly larger tire (perhaps a 31-inch diameter tire depending on your stock size), but it's highly dependent on the factors mentioned above.
To find the best answer for *your* Suburban:
1. Check your current tire size: This information is usually on the sidewall of your tire.
2. Consult online forums: Search for 1991 GMC Suburban forums (e.g., on sites like GMC Sierra forums or dedicated truck forums). Owners have often documented their tire upgrades, both with and without lifts. Look for posts related to your specific trim level.
3. Measure your clearance: Carefully measure the space between your tires and the fenders, both at the top and sides.
Recommendation: Start with a conservative upgrade. Even a slightly larger tire can lead to significant rubbing if not carefully considered. It is always better to err on the side of caution to avoid damage to your vehicle. Consider a professional tire shop's opinion; they may have experience with similar vehicles and can assess your clearance.
