ATP TF-29 Automatic Transmission Filter Kit | GM TH400 (Turbo 400) 1968-1990

ATP TF-29 Automatic Transmission Filter Kit — GM TH400 (Turbo 400)

Servicing a classic GM Turbo Hydramatic 400? Dark, dirty, or burnt-smelling ATF, sluggish engagements, and a whining pump are all signs your TH400 is overdue for a fluid and filter service. The ATP TF-29 kit gives you the two parts every TH400 pan-drop needs: a replacement filter and a new pan gasket.

The TH400 (also known as the Turbo 400, TH375, M-40, or 3L80) is one of GM's most widely used three-speed automatics, found across GM cars, trucks, and vans from roughly 1968 to 1990 — and even in Rolls-Royce, Bentley, and Jaguar models that bought the transmission from GM.

Part Numbers

• ATP TF-29
• TF29

Application: GM Turbo Hydramatic 400 automatic transmission (TH400 / TH375 / M-40 / 3L80).

Aftermarket Cross Reference

• WIX 58890
• FRAM FT1020

Verified TH400 service-kit equivalents. Always match the filter to the transmission (TH400), not the vehicle model alone.

When to Service (Common Symptoms)

• Scheduled ATF service — fluid dark, dirty, or with a burnt smell
• Delayed or harsh gear engagements
• Pump whine caused by a clogged, starving filter
• Any pan-off repair — always install a fresh filter and gasket

Product Highlights

• ✔ Complete service kit: transmission filter plus pan gasket
• ✔ ATP "3rd Hand" fiber pan gasket — undersized bolt holes grip the bolts and hold the gasket in place during installation
• ✔ Fits the GM Turbo 400 used across GM cars and trucks, approx. 1968–1990
• ✔ OE-quality replacement for routine fluid and filter service
• ✔ Made in USA

Condition

New

Product Type

Automatic Transmission Filter Kit (filter + pan gasket)

Function

The transmission filter sits inside the pan and screens debris out of the ATF before it reaches the pump and valve body. A clogged filter starves the pump, causing whine, delayed engagement, and accelerated wear. On the TH400 the filter is serviced by dropping the pan — plan for roughly 6 quarts of fresh fluid — and the kit's new gasket seals the pan on reassembly.

Compatible Vehicles

Vehicles equipped with the GM TH400 automatic transmission, approx. 1968–1990, including:

• Chevrolet / GMC C/K and G-series trucks and vans, Suburban
• Chevrolet Corvette, Camaro
• Buick (incl. Skylark 1968–1969)
• Cadillac
• Oldsmobile
• Pontiac
• Full-size Jeep models with TH400
• Rolls-Royce, Bentley, and Jaguar models equipped with the GM TH400

Important: Fitment is determined by the transmission, not the vehicle model — confirm your vehicle has a TH400 before ordering. Please verify fitment with your VIN before ordering.

Package Contents

• 1 × Automatic transmission filter
• 1 × Transmission pan gasket

Technical Specifications

Brand	ATP
Part Number	TF-29
Alternate Part Number	TF29
Seller SKU	RA_TF29
Product Type	Automatic Transmission Filter Kit
Transmission	GM TH400 / TH375 / M-40 / 3L80 (Turbo Hydramatic 400)
Application Years	approx. 1968–1990
UPC	00740993903062
Country of Origin	USA
Condition	New

Warranty

Manufacturer warranty may vary by supplier, seller, and region. Please contact us before purchase if warranty confirmation is required.

Installation Video

▶ TH400 Transmission Oil & Filter Change — Class A Living

FAQ

Which transmission does this kit fit?

The GM Turbo Hydramatic 400 — also badged TH400, Turbo 400, TH375, M-40, or 3L80 — used in GM vehicles from roughly 1968 to 1990.

Will it fit a TH350, 700R4, or 4L60E?

No. Those transmissions use different filters and gaskets. This kit is for the TH400 family only.

What is included in the kit?

A replacement transmission filter and a pan gasket — everything a standard TH400 pan-drop service needs.

How much transmission fluid will I need?

A pan-drop service on a TH400 typically takes about 6 quarts of ATF.

What is the "3rd Hand" gasket?

ATP's fiber pan gasket with slightly undersized bolt holes: the gasket grips the pan bolts and stays aligned while you lift the pan into place — like having a third hand during installation.