Bathtub Drain Replacement Guide

A damaged or slow bathtub drain is one of the most common plumbing complaints in any home. Whether you are dealing with a cracked strainer, a broken stopper mechanism, a corroded drain body, or persistent slow drainage that cleaning cannot fix, the solution is often a complete drain assembly replacement.

This guide covers everything you need to know to remove an old bathtub drain and install a new one correctly — including the different drain types, the tools required, and the critical step that prevents the most common cause of post-installation leaks.

Understanding Bathtub Drain Systems

A bathtub drain is not a single component — it is an assembly of parts that work together to drain water from the tub and seal it when the stopper is closed. Understanding the full system helps you identify which components need replacement and which are fine.

Components of a Standard Bathtub Drain

Drain strainer / drain body: The visible part in the tub floor. A flanged fitting with a threaded shank that passes through the tub floor and connects to the drain shoe below. Made from chrome-plated brass, stainless steel, or plastic.

Drain shoe (drain elbow): Located underneath the tub, the drain shoe is the elbow-shaped fitting that connects the vertical drain body to the horizontal drain pipe. The shoe has a threaded socket that accepts the drain body’s shank and an outlet that connects to the P-trap.

Overflow plate: Located on the tub wall just below the rim, the overflow plate covers the overflow opening — the drain that prevents the tub from overflowing when the main drain is closed and the water level rises too high. The stopper mechanism in most tubs is housed here.

Overflow tube: The pipe that connects the overflow plate to the drain shoe below, allowing excess water to drain before it reaches the tub rim.

P-trap: Located below the drain shoe, the P-trap maintains a water seal that prevents sewer gases from entering the bathroom through the drain.

Types of Bathtub Drain Stoppers

Different stopper mechanisms require different replacement approaches. Identifying your stopper type before purchasing parts is essential.

Lift-and-Turn Stopper

A knob on the strainer is lifted and rotated to open or close the drain. The stopper sits directly in the drain opening. To remove: lift the stopper, hold the body steady, and unscrew the center knob counterclockwise. Lift the stopper out.

Push-Pull Stopper

Similar to lift-and-turn but opens and closes by pushing straight down rather than rotating. The stopper is removed the same way — unscrew the center knob.

Toe-Touch (Foot-Actuated) Stopper

Pushed down to close, pushed again to open via a spring mechanism. Remove by lifting and turning counterclockwise (the stopper unscrews from the drain body).

Trip Lever (Plunger Style)

The lever on the overflow plate connects via a brass linkage to a plunger inside the overflow tube. The plunger blocks or opens the drain shoe at the base of the overflow tube rather than at the strainer level. These are common in older homes. The visible strainer in the tub floor has no stopper function — it is just a screen.

To service a trip lever drain: remove the two screws on the overflow plate, pull the plate and attached linkage out of the overflow tube, clean or replace as needed.

Pop-Up Stopper

The overflow plate lever connects via a rocker arm and lift rod to the stopper in the drain opening. Pushing the lever down raises the stopper (opens the drain); pulling the lever up closes it. To remove the stopper: lift it out (it should come free with the attached rocker arm).

When to Replace vs. When to Clean

Replace the drain assembly when:

The drain body or strainer is visibly cracked, broken, or corroded through
The stopper mechanism no longer holds water or is mechanically failed and cannot be adjusted
There is water leaking under the tub from the drain body connection
The drain body threads are stripped or damaged
You are remodeling and want to update the finish

Clean first when:

The drain is slow but the hardware looks intact
The stopper does not hold water but the mechanism feels functional
There is hair and soap scum buildup

For cleaning: remove the stopper (see type-specific instructions above), use a drain snake or Zip-It tool to clear the P-trap, and clean the strainer and stopper seal with white vinegar to remove mineral deposits.

Tools and Materials You Will Need

Tools:

Drain wrench or drain extractor (essential — more on this below)
Channel-lock pliers (large)
Flathead screwdriver
Utility knife
Putty knife
Adjustable wrench
Wire brush

Materials:

New drain assembly (drain body + strainer, or complete kit)
Plumber’s putty
PTFE tape
Silicone caulk (tub-rated)
Bucket and towels

The Drain Wrench: The Right Tool for This Job

Removing the old drain body is the most physically challenging part of this project. The drain body has cross slots on its interior — like a giant flathead screw — that accept a specialized tool called a drain wrench (also called a drain extractor or tub drain remover).

Do not attempt to remove the drain body with a large screwdriver jammed into the slots. You will strip the slots and potentially crack the tub floor, making the job exponentially more difficult.

Recommended drain wrenches:

RIDGID 42577 EZ Change Drain Wrench — inserts into the drain body and grips from inside, turning the whole body out. Handles both standard and deep-set drains.
Danco 11065X Tub Drain Remover — a two-claw extractor that grips the cross slots. Affordable and works on most standard drain bodies.
General Wire TDX Tub Drain Extractor — professional-grade tool with an X-shaped head that grips all four cross slots simultaneously for maximum torque.

The drain wrench inserts into the drain opening, locks onto the cross slots inside the drain body, and is turned with a wrench or drill to unscrew the drain body counterclockwise from the drain shoe threads below.

Step-by-Step: Removing the Old Drain Assembly

1. Remove the Stopper

Based on the stopper type (see above), remove the stopper from the drain opening. For trip lever and pop-up styles, also remove the overflow plate by unscrewing the two screws securing it to the overflow box.

Set all stopper components and hardware aside.

2. Apply Penetrating Oil (If Needed)

If the tub is older or the drain body has not been removed in years, apply a penetrating lubricant (PB Blaster or WD-40) to the visible threads at the top of the drain body. Let it soak for 15 to 30 minutes. This can be the difference between a drain body that breaks free in 30 seconds and one that fights you for 30 minutes.

3. Insert the Drain Wrench

Insert the drain wrench into the drain opening so it engages the cross slots inside the drain body. For claw-type extractors, turn the center bolt clockwise to expand the claws and grip the slots.

4. Unscrew the Drain Body

Using a large adjustable wrench or pliers on the drain wrench handle, turn counterclockwise (when viewed from above). Apply steady, firm pressure. The drain body is typically threaded right-hand (lefty-loosey), so counterclockwise loosens it.

If it will not budge: Add more penetrating oil. Let it sit longer. Try applying heat with a hair dryer to the tub floor around the drain (if it is a fiberglass or acrylic tub, be conservative with heat). Impact driving the drain wrench (short sharp turns) can also break loose a stubborn drain.

5. Remove the Drain Body

Once loosened, remove the drain body by hand. Inside the drain opening, you will see the drain shoe below with its threaded center socket and old plumber’s putty or silicone around the flange.

6. Clean the Drain Opening

Use the putty knife to scrape away old plumber’s putty from the tub floor around the drain opening. Clean the tub surface thoroughly. Inspect the drain shoe threads below — they should be intact and free of debris.

7. Remove Old Overflow Plate (If Replacing)

Unscrew the two screws holding the overflow plate to the overflow box. Pull the plate and linkage assembly out of the overflow tube (it will pull straight out). Inspect the overflow tube for scale buildup and clean if necessary.

Choosing a New Drain Assembly

Full Replacement Kits

The cleanest approach is a complete drain kit that includes the drain body, strainer, overflow plate, overflow tube, stopper mechanism, and drain shoe. These kits ensure all components match and seal correctly together.

Recommended complete kits:

Watco 901-SS-BF Universal Tub Drain Kit One of the most popular and widely stocked drain kits available. The Watco 901 includes the drain strainer, overflow plate, overflow tube (adjustable length), and lift-and-turn stopper. It fits most standard tub configurations and installs without specialty tools beyond the drain wrench. Available in chrome, brushed nickel, matte black, and oil-rubbed bronze.

Overflow tube: Adjustable from 10 to 14 inches
Drain body thread size: 1-7/8-inch x 16 TPI (standard for U.S. tubs)
Compatible tub types: Fiberglass, acrylic, cast iron, steel

Dearborn Brass 101BC Trim Kit with Trip Lever Dearborn is a long-established brand in drain hardware. Their 101BC trip lever kit is a direct replacement for most original trip lever drain assemblies found in older American homes. The plunger-style stopper mechanism is robust and less prone to failure than some mechanical stopper designs.

Overflow tube: 10-1/2 to 14-1/2 inches (adjustable)
Stopper type: Trip lever plunger
Available finishes: Chrome, brushed nickel

Watco 707 PopUp Trim Kit For tubs where a pop-up stopper is preferred. The pop-up mechanism is operated by the overflow plate lever and uses a rocker arm linkage to the stopper in the drain opening. Clean, intuitive operation.

Drain Body Only (When the Shoe is Fine)

If only the drain body and strainer need replacement — the shoe below is intact and properly threaded — you can purchase a drain body alone.

Danco 9D00080462 1-7/8-Inch Tub Drain Strainer A straightforward chrome-plated drain strainer that threads into the existing drain shoe. Includes cross slots for the drain wrench.

Standard drain body thread size: 1-7/8 inches diameter x 16 threads per inch (TPI). This is the standard for virtually all U.S. residential bathtubs. The exception is some very old cast iron tubs which may use 1-7/8 inches x 11-1/2 TPI.

Step-by-Step: Installing the New Drain Assembly

1. Apply Plumber’s Putty to the Drain Flange

Roll a rope of plumber’s putty approximately 3/8-inch in diameter and press it around the underside of the new drain body’s flange (the flat ring that will sit on the tub floor). Apply it all the way around so there are no gaps.

Do not use silicone for this step. Plumber’s putty remains pliable and seals the gap between the flange and the tub floor. Silicone can also be used — and is required on some surfaces — but plumber’s putty is standard for most tub drain installations.

Exception: If the tub is acrylic or fiberglass, some manufacturers advise against plumber’s putty (it can stain these surfaces over time). In that case, use silicone caulk rated for tub applications, or use a drain kit that includes a rubber gasket instead of requiring putty.

2. Thread the New Drain Body In

Lower the drain body into the drain opening, engaging the threads with the drain shoe below. Turn clockwise by hand until snug, then use the drain wrench to tighten fully. The drain body is fully seated when the flange sits flat against the tub floor with the putty squeezing out evenly around the circumference.

How tight? Firm — the flange should not move or wobble — but not so tight that the tub floor flexes or the drain body cross slots strip. For cast iron tubs, you can apply considerably more torque than for fiberglass.

3. Remove Excess Putty

Once the drain body is tight, excess plumber’s putty will have squeezed out from under the flange. Remove it with your finger or a plastic putty knife. Clean up any residue with a damp cloth.

4. Apply PTFE Tape to Overflow Tube Threads (If Applicable)

If your kit includes a separate overflow tube that threads into the drain shoe or overflow box, wrap the male threads with two to three layers of PTFE tape before threading it in.

5. Install the Overflow Tube and Plate

If you removed the overflow tube, reinstall it into the overflow box (the access point behind the tub, inside the wall). Most overflow tubes have a slip nut connection at the drain shoe end and a threaded or friction-fit connection at the overflow box.

Set the overflow plate in position, connect the stopper linkage according to the kit instructions, and secure the plate with the two screws. Do not overtighten — you are threading into plastic or soft metal.

6. Install the Stopper Mechanism

Follow the kit-specific instructions for your stopper type. For lift-and-turn: thread the center post into the drain body. For trip lever: set the plunger depth by adjusting the threaded linkage rod (see below). For pop-up: connect the rocker arm to the stopper and set the linkage.

Adjusting a trip lever mechanism: The plunger must be adjusted so that it completely blocks the drain shoe opening when the lever is in the closed position, and fully clears it when open. With the overflow plate installed and the lever in the open position, pull the overflow plate slightly away from the wall and reach in to feel if the plunger is fully retracted. Adjust the linkage nut up or down on the threaded rod to achieve proper positioning.

7. Test Before Finishing

Fill the tub with several inches of water with the stopper closed. Check that:

The stopper holds water without significant loss over 5 minutes
The drain body is not leaking (check from below if you have access)
The overflow plate is properly sealed

Open the stopper and watch the water drain. It should drain freely without backing up or gurgling excessively.

If you have access from below (crawl space or basement), visually inspect the drain shoe connection during the water test for any drips.

Troubleshooting After Installation

Stopper does not hold water: On trip lever designs, the plunger is not seating correctly — adjust the linkage. On stopper-in-drain designs, check that the rubber gasket on the stopper is intact and seated correctly.

Drain leaks from under the flange: The plumber’s putty or silicone seal failed. Remove the drain body, clean the surfaces thoroughly, and reinstall with fresh putty applied evenly.

Drain body will not tighten fully: The drain shoe threads may be damaged or crossed. Remove the drain body and inspect the shoe threads. Minor cross-threading can sometimes be corrected by carefully re-engaging the threads straight. Significant damage requires shoe replacement.

Slow drainage after replacement: The new drain assembly is not the cause — the clog is in the P-trap or further down the drain line. Use a hand drain snake to clear the P-trap.

Plumber’s Putty vs. Silicone: Which to Use

Scenario	Use Plumber’s Putty	Use Silicone
Cast iron or steel tub	Yes	Optional
Fiberglass or acrylic tub	Check manufacturer — putty may stain	Yes (tub-rated)
Kit includes rubber gasket	Neither needed	Apply to flange rim if specified
Drain body will not be serviced again soon	Putty (stays pliable, easy to remove later)	Silicone (stronger initial bond)

Cost Summary

Component	DIY Cost	Plumber Cost
Basic drain strainer only	$8–$20	—
Complete drain kit (Watco, Dearborn)	$30–$80	$150–$300 installed
Drain wrench (purchase)	$15–$35	—
Plumber’s putty	$3–$6	—
Total DIY (complete replacement)	$50–$140	$150–$300

Renting a drain wrench from a hardware store is often possible for $5 to $10 if you do not want to purchase one.

Conclusion

Replacing a bathtub drain is a moderate-difficulty DIY project. The critical tools are the drain wrench (non-negotiable) and the right replacement kit for your stopper style. Using plumber’s putty correctly under the flange and verifying the installation with a water test before declaring the job done are the two steps that separate a lasting repair from one that leaks in six months.

Choose a quality drain kit from Watco or Dearborn — both have excellent track records and are widely stocked in hardware stores if you need to return for additional parts. The Watco 901-SS universal kit fits the vast majority of American bathtubs and installs cleanly in an afternoon.