What Are Wheel Tubs and Why Do You Need Them?

Wheel tubs are the inner wheel housings that surround your rear tires. You need them when the tire you want to run is wider than your stock wheelhouses can clear.

Factory wheelhouses are sized for factory tires. Step up to a wide drag radial or slick, and the tire can rub the inner sheet metal. Aftermarket rear wheel tubs move that inner wall inboard to give the tire room.

Tire choice drives every tub decision. If you haven't picked rubber yet, compare drag radials vs. slicks before you order tubs or start cutting.

Tubs are also part of a bigger sheet metal job. You'll often trim, weld or replace nearby panels, so plan the whole rear section with our sheet metal and body panels, including quarter panels. Settle tire width, tub size and panel work up front so you don't cut twice.

Mini Tubs vs. Full Wheel Tubs: Which Fits Your Build?

Choose mini tubs if you want more tire while keeping your stock frame and rear seat. Choose full wheel tubs if you're running large drag slicks and you're ready for major chassis work.

A mini tub kit usually fits inside the existing frame or subframe, though some cars need frame notching. Mini tubs typically gain you 2-3 in. of backspacing, and some kits reach 4 in. You'll often need to move the leaf springs and shocks inboard to make room.

Full tubs clear much bigger tires, but they require extensive modification. Most builds need a rear frame rail kit, and the larger tubs cut into rear seat space. JEGSTER offers chassis components such as 4-link rear frames and roll cages that pair with a full-tub build.

If your car still sees the street, start with mini tubs. If you're chasing quarter-mile times on slicks, plan for full tubs.

Steel, Aluminum, or Carbon Fiber Wheel Tubs?

Pick steel if you want a weld-in tub, aluminum if you'd rather glue or rivet, and carbon fiber for a composite race tub. Here's how the materials compare, with specific tubs you can shop.

• Steel wheel tubs: Competition Engineering 247-3008 tubs use 24-gauge steel, measure 38" L x 23-1/4" W x 19" H, and have a Pittsburgh locking seam and bead-rolled ribs.
• Aluminum wheel tubs: Rhodes Race Cars offers a 40 in. aluminum tub, and the Competition Engineering 3007 measures 36" L x 23-1/4" W x 18" H.
• Carbon fiber wheel tubs: Wildside Composites tubs combine a carbon fiber front with fiberglass backing in 36, 40 and 46 in. lengths.
• Stamped steel mini tubs: Detroit Speed mini-tub wheel housings use 18-gauge stamped steel and retain a stock exterior appearance.

Your install method matters too. Steel tubs are welded in, while aluminum tubs can be glued or riveted. Compare each tub's length, width and height to your wheel opening before you order.

How Do You Measure for Rear Wheel Tubs?

Start with the tire and wheel you plan to run, then work inward to the frame. Your tire width, wheel backspacing and the distance between the frame rails decide which rear wheel tubs will fit.

Measure in this order:

• Tire width: Confirm the section width of the tire you'll run, since it sets the minimum tub width.
• Wheel backspacing: Measure from the mounting pad to the inner lip, since more backspacing pushes the tire inboard.
• Frame rail distance: Measure the clearance between the tire's inner sidewall and the frame rail.
• Springs and shocks: Check whether leaf springs and shocks must move inboard to clear the wider tire.

Wheel size and tire size work together, so review what size racing wheels to run for drag racing before you finalize numbers. Then shop wheels and tires that match your backspacing target.

If the frame rails are in the way, you're likely looking at notching or full tubs with a rear frame rail kit.

Wheel Tubs for Trucks and Classic Muscle Cars

Vehicle-specific mini tub kits are the simplest way to add tire width to a classic muscle car or pickup. They're built for your chassis, so fitment is more predictable than a universal tub.

Detroit Speed mini-tub wheel housings for 1967-1969 GM F-Body cars clear up to a 335 mm tire, up to 3" wider than stock. Its 1962-1967 Chevy II kit fits up to a 315 mm tire, 2.5" wider than stock. You'll also find kits for 1968-1974 GM X-body cars and 1970-1981 Camaros.

For wheel tubs for trucks, look at a +4 in. wide inner wheelhouse mini tub panel for 1973-1986 GM C/K pickups. It's made from 18-gauge steel with an EDP coating.

Suspension changes usually come with the tubs. Moving springs and shocks inboard, or switching to a 4-link, changes how the rear end locates. Read our 4-link suspension setup guide, then shop chassis, steering and suspension parts.

Finish the job with matching fenders and inner fenders so the new tubs tie cleanly into the rest of the body.