Filter & Pan Gasket
Kit by Model

A fluid-and-filter service is the cheapest insurance you can buy for an automatic transmission, and it is the single job most often botched at home. Not because it is hard, but because people buy the wrong filter, reuse a crushed gasket, or pick a kit that ships with a paper gasket when the pan needs RTV. The result is a fresh leak, a clean garage floor turned into a slick, and a comeback within a week.

This guide is organized the way you actually shop: by transmission model. Find your unit, see what filter style it takes, what gasket seals it, and what is in the kit worth buying.

Filter Style by Model — Read This First

There is no universal transmission filter. The style is dictated by the pan and the pump pickup. Buy the wrong one and it either will not seat or it starves the pump. Three families:

• Felt / fiber pickup filter: the classic GM and Ford style. A flat pan filter with a rubber-grommeted neck that presses into the pump bore. 4L60E, 4L80E, 4R70W, AOD all use this. The grommet is the part that fails — buy a kit that includes a new one.
• Deep-pan / extended filter: if you run an aftermarket deep pan you need the matching tall filter, or the standard filter sits an inch above the fluid and sucks air on hard corners. Never mix a stock filter with a deep pan.
• Cartridge / spin-on: many late-model units (ZF 8HP, some 6L80 service kits, 68RFE has both an internal and a spin-on external) use a serviceable cartridge plus a separate external spin-on. Miss the external one and you have only done half the service.

Kits by Transmission

Note the ZF 8HP line: on most 8HP applications the filter is bonded to the plastic pan, so you replace the entire pan-and-filter as one assembly. Trying to reuse the old pan to save money is false economy — the integrated gasket does not reseal.

RTV vs Rubber Gasket — The Leak Decision

This is where most home services go wrong. The rule:

• Reusable molded rubber gasket (4L60E, 4L80E, 6L80): install dry. No RTV. The gasket is designed to be torqued to spec and reused for several services. Smearing silicone on it makes it slip and squeeze out, which is exactly how you get a leak you blame on the gasket.
• Cork or paper gasket: a thin film of RTV on the pan side only, to hold it in place during install. Never goop both sides.
• RTV-only pans (no gasket called out): some units seal with anodized aluminum pan-to-case and a bead of OEM-spec gray RTV. Clean both surfaces to bare metal, lay a 1/8-inch continuous bead inside the bolt holes, and torque within the RTV skin time.

And the universal mistake regardless of gasket type: over-torquing the pan bolts. A transmission pan bolt is usually 8 to 12 ft-lbs, not 30. Crank them down and you dish the pan rail between bolts, which guarantees a leak no gasket can fix. Use a quarter-inch torque wrench and a star pattern.

1/4-inch torque wrenches

What to Buy

OE-Style Filter Kits (GM Units)

For a 4L60E, 4L65E, or 4L80E, buy a kit that ships the felt filter, a fresh pickup grommet, and a reusable rubber pan gasket together. ACDelco and Pioneer kits both include the grommet, which the cheapest no-name kits skip. A reused or dry-rotted grommet leaks air into the pump and causes a slip that looks like a failing transmission but is a five-dollar part.

4L60E filter and gasket kits4L80E kits →

68RFE — Do Not Forget the External Spin-On

The 68RFE has an internal filter inside the pan AND an external spin-on cooler-return filter near the bell housing. People drop the pan, change the internal, and skip the spin-on because they did not know it existed. Buy the kit that includes both, and a fresh pan gasket.

68RFE complete filter kits

6L80 / 6L90

The 6L80 uses a cartridge filter and a one-piece molded gasket. This unit is sensitive to fluid level and uses a fill-from-below procedure with no dipstick, so do the service right or you will be chasing a shudder afterward. Buy the kit with the molded gasket, not a paper substitute.

6L80 filter kits

Deep Pan + Tall Filter

If you are upgrading to a finned aluminum deep pan for towing, you must run the matching tall filter or a filter spacer/extension. The pan brand usually lists the correct filter. Order them together.

Deep pan and filter combos

Service Checklist

• Confirm filter style and grommet are correct for your exact model and pan.
• Clean the pan magnet and the pan rail to bare metal.
• Install reusable rubber gaskets dry; light RTV only on cork or paper.
• Torque pan bolts to spec in a star pattern (typically 8 to 12 ft-lbs).
• Refill with the exact OE fluid spec, then check level at the correct temperature window.

FAQ

Do I really need a new gasket every service?

Not always. Molded rubber gaskets on 4L60E, 4L80E, and 6L80 are reusable if they are not torn or dished. Cork, paper, and bonded gaskets are one-time use — replace them.

Can I reuse the old filter if it looks clean?

No. The filter media loads up with clutch material you cannot see, and the pickup grommet hardens with age. A filter is a few dollars; reusing it to save money risks the whole unit.

Why does my pan leak after I changed the gasket?

Almost always over-torqued bolts dishing the pan rail, or RTV on a gasket that should have gone in dry. Pull it, inspect the rail for warpage, and reinstall to spec.