GM Blazer/Jimmy/Typhoon/Bravada 1983-1993 Repair Guide

Tires and Wheels


See Figures 1, 2, 3 and 4

Inspect your tires often for signs of improper inflation and uneven wear, which may indicate a need for balancing, rotation, or wheel alignment. Check the tires frequently for cuts, stone bruises, abrasions, blisters and for objects that may have become embedded in the tread. More frequent inspections are recommended when rapid or extreme temperature changes occur, or where road surfaces are rough and/or occasionally littered with debris. Check the condition of the wheels and replace any that are bent, cracked, severely dented or have excessive run-out.

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Fig. Fig. 1: Uneven tire wear can be caused by variables from tire/vehicle condition to driving style

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Fig. Fig. 2: Tread depth can be checked using an inexpensive gauge

The tires on your truck have built-in wear indicators molded into the bottom of the tread grooves. The indicators will begin to appear as the tire approaches replacement tread depth. Once the indicators are visible across 2 or more adjacent grooves at 3 or more locations, the tires should be replaced.

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Fig. Fig. 3: If a gauge is not available, a penny may be used to check for tire tread depth; when the top of Lincoln's head is visible, it is probably time for a new tire

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Fig. Fig. 4: If tires a used beyond the point of tread life, built-in wear indicators will begin to appear as lines perpendicular to the tread

Wear that occurs only on certain portions of the tire may indicate a particular problem, which when corrected or avoided, may significantly extend tire life. Wear that occurs only in the center of the tire indicates either overinflation or heavy acceleration on a drive wheel. Wear occurring at the outer edges of the tire and not at the center may indicate underinflation, excessively hard cornering or a lack of rotation. If wear occurs at only the outer edge of the tire, there may be a problem with the wheel alignment or the tire, when constructed, contained a non-uniformity defect.


Tire rotation is recommended every 6,000 miles or so, to obtain maximum tire wear. The pattern you use depends on whether or not your truck has a full-sized usable spare or an undersized "donut" spare. Because the compact or donut spare tire is designed for limited emergency use, it should not be included in normal tire rotation.

Due to their design, radial tires tend to wear faster in the shoulder area, particularly in the front positions. Radial tires in non-drive locations, may develop an irregular wear pattern that can generate tire noise. It was originally thought the radial tires should not be cross-switched (from one side of the truck to the other); because of their wear patterns and because they would last longer if their direction of rotation is not changed. The manufacturer's tire rotation recommendations for most late model trucks covered by this vehicle now allows for, and even suggest, cross-switching radial tires to allow for more uniform tire wear.

Some specialty aftermarket tires may be directional (certain snow or off-road tires), meaning they may only be mounted to rotate in one direction. Some snow tires and special performance tires/wheels will fall into this category and will be marked with directional rotation arrows on the tire sidewalls. NEVER switch the direction of rotation on tires so marked or poor performance/tire damage could occur. This should be taken into consideration in choosing a rotation pattern for directional tires.


For maximum satisfaction, tires should be used in sets of five. Mixing of different types (radial, bias-belted, fiberglass belted) should be avoided. Conventional bias tires are constructed so that the cords run bead-to-bead at an angle. This type of construction gives rigidity to both tread and sidewall. Bias-belted tires are similar in construction to conventional bias ply tires. Belts run at an angle and also at a 90° angle to the bead, as in the radial tire. Tread life is improved considerably over the conventional bias tire. The radial tire differs in construction, but instead of the carcass plies running at an angle of 90° to each other, they run at an angle of 90° to the bead. This gives the tread a great deal of rigidity and the sidewall a great deal of flexibility and accounts for the characteristic bulge associated with radial tires.

Most of these trucks are capable of using radial tires and they are recommended. If they are used, tire sizes and wheel diameters should be selected to maintain ground clearance and tire load capacity equivalent to the minimum specified tire.

Most snow tires should not be operated at sustained speeds over 70 mph.

Although mixing tire sizes and tread patterns is not recommended for all vehicles, it is even less wise on four wheel drive trucks. On four wheel drive trucks, tires of the same size, type, and tread pattern are necessary to provide even traction on loose surfaces, to prevent driveline bind when conventional four wheel drive is used, and to prevent excessive wear on the center differential with full time four wheel drive.

When buying new tires, give some thought to the following points, especially if you are considering a switch to larger tires or a different profile series:

  1. All tires must be of the same construction type. This rule cannot be violated, radial, bias, and bias-belted tires must not be mixed or vehicle handling and safety may be seriously jeopardized.
  3. The wheels should be the correct width for the tire. Tire dealers have charts of tire and rim compatibility. A miss-match will cause sloppy handling and rapid tire wear. The tread width should match the rim width (inside bead to inside bead) within an inch. For radial tires, the rim should be 80% or less of the tire (not tread) width.
  5. The height (mounted diameter) of the new tires can change speedometer accuracy, engine speed at a given road speed, fuel mileage, acceleration, and ground clearance. Tire manufacturers furnish full measurement specifications.
  7. The spare tire should be usable, at least for short distance and low speed operation, with the new tires.
  9. There shouldn't be any vehicle body interference when loaded, on bumps, or in turns. If the tire hits the wheel-well under load, wear and the possibility of a blow-out will be significantly increased.


Store the tires at the proper inflation pressure if they are mounted on wheels. Keep them in a cool dry place, on their sides. If the tires are stored in the garage or basement, DO NOT let them stand on a concrete floor; set them on strips of wood.


Tire inflation may be the most ignored item of auto maintenance. Gasoline mileage can drop as much as 0.8% for every 1 pound/square inch (psi) of under-inflation. Tires should be checked weekly for proper air pressure. A chart should be located either in the glove compartment, on one of the vehicle's doors or door jambs and/or in the owners manual. This chart will provide the recommended inflation pressures. Maximum fuel economy and tire life will result if the pressure is maintained at/near the highest figure given on the chart.

Pressures should be checked with the tires cold (before driving 1 mile or more) since pressure can increase as much as six pounds per square inch (psi) due to heat buildup as the tire is warmed. It is a good idea to have your own accurate pressure gauge, because many gauges on service station air pumps cannot be trusted. When checking pressures, do not neglect the spare tire. Note that some spare tires require pressures considerably higher than those used in the other tires.

While you are about the task of checking air pressure, inspect the tire treads for cuts, bruises and other damage. Check the air valves to be sure that they are tight. Replace any missing valve caps. Dirt and moisture gathering in the valve stem could lead to an early demise of the stem and a subsequent flat tire.

Before starting a long trip with lots of luggage, you can add about 2-4 psi to the tires to make them run cooler, but never exceed the maximum inflation pressure on the side of the tire. Factory installed wheels and tires are designed to handle loads up to and including their rated load capacity when inflated to the recommended inflation pressures. Correct tire pressures and driving techniques have an important influence on tire life. Heavy cornering, excessively rapid acceleration and unnecessary braking increase tire wear. Underinflated tires can cause handling problems, poor fuel economy, shortened tire life and tire overloading.


If your truck is equipped with aluminum wheels (such as from an aftermarket application), they are normally coated to preserve their appearance. To clean the aluminum wheels, use a mild soap and water solution, then rinse thoroughly with clean water. If you want to use one of the commercially available wheel cleaners, make sure the label indicates that the cleaner is safe for coated wheels. Never use steel wool or any cleaner that contains an abrasive, or use strong detergents that contain high alkaline or caustic agents, as they will damage your wheels.