8F35 Overhaul Kit 2018-2025

If your Ford Edge, Escape, Bronco Sport, Maverick, Lincoln Nautilus or Corsair has an 8F35 that slips when hot, engages Drive or Reverse late, or weeps fluid at the case, the unit is coming out and it needs to be resealed. This is a new Precision overhaul kit for the 8F35, listed for 2018-2025, with the gasket set, sealing rings and seals plus replacement pistons. It is the sealing side of a rebuild, the parts that let every clutch circuit hold pressure again after the hard parts are inspected.

What the overhaul kit does in an 8F35

The 8F35 builds eight forward ratios by applying clutches and brakes around its planetary sets, and every one of those apply circuits is a rubber-sealed piston fed through sealing rings on rotating shafts. The fluid is Mercon ULV, a very thin oil, so a seal that has taken a set or a ring with worn edges leaks more than it would with a heavier fluid. The valve body then has to apply a clutch through a leaking circuit, and the PCM sees slip time it keeps adapting around until it runs out of room. Bonded pistons are the other weak point: the rubber is molded to the metal, so when the lip hardens or tears the whole piston gets replaced, not just a seal. Having the pistons in the same box as the gaskets and rings means the teardown does not stall waiting on them.

Symptoms that point to a reseal

• Delayed engagement into Drive or Reverse after the vehicle sits overnight
• Slip or flare on upshifts once the fluid is fully hot
• Harsh or banging engagement as the PCM raises pressure to cover leakage
• Fluid at the case seams, pan or side cover
• Slip-related codes that come back after a fluid change and adaptive reset

How to confirm before you buy

Not every 8F35 complaint is a seal problem. Ford fixed a low-speed shudder with PCM software and traced P0766 with intermittent no reverse to a contaminated separator plate orifice, and neither needs an overhaul. Units built on or before December 20, 2021 can also lose the output planet carrier needle bearings, which fills the transmission with debris. Pull the pan and look at the fluid and filter before you commit. Our 8F35 bulletin guide lays out each fix and which build dates it covers, so you can tell a reseal job from a software or carrier repair.

Fitment

The kit is listed for 8F35 transmissions from 2018 to 2025. Ford's 8F family went into production for 2019, and in the US the 8F35 is found in the 2019-up Edge and Nautilus, 2020-up Escape and Corsair, 2021-up Bronco Sport and 2022-up Maverick. If your vehicle is a 2018, it almost certainly has an earlier six-speed, so check before you order. The 8F24, 8F35, 8F40 and 8F57 are related units with different solenoid layouts and valve body castings, so read the transmission tag or send us your year and VIN, and compare the pistons and gaskets to your originals at teardown. Everything else we carry for this transmission is in the 8F35 parts collection.

Install notes

• This is a gasket, seal and piston kit. If the clutch packs are burnt or glazed, pair it with the 8F35 kit with frictions, steels and filter.
• Soak lip seals and piston seals in clean Mercon ULV before assembly, size the Teflon rings so they do not cut on installation, and air-check every clutch circuit before the case is closed.
• The pump drive chain and gear can drop out of place when the converter housing and torque converter go on, leaving a no-pressure unit. Support them and install the converter with the transmission standing vertical.
• Inspect the output carrier needle bearings and replace the carrier on affected builds rather than resealing around a failing part. Check the 8F35 pump and the input drum for scoring while the unit is apart.
• Refill with Mercon ULV only, clear adaptive tables with a scan tool and complete the relearn drive.

Does this 8F35 overhaul kit include clutch frictions?

No. It is the gasket set, sealing rings and seals with replacement pistons. If your frictions are burnt or glazed, add a friction and steel kit for the 8F35.

Will it fit my 2018 Escape or Edge?

The 8F family went into production for the 2019 model year, so a 2018 Escape or Edge has an earlier transmission. Check the transmission tag, or send us your year and VIN before you order.

Does it fit the 8F24 in a Bronco Sport or Escape with the smaller engine?

The 8F24 and 8F35 are related, but they differ in solenoid layout and valve body casting. We list this kit for the 8F35, so confirm your unit from the tag or VIN before ordering.

What fluid does the 8F35 use after the rebuild?

Ford specifies Mercon ULV for the 8F35. Do not substitute Mercon LV or a multi-vehicle fluid.

What else should I replace while the 8F35 is apart?

Replace the frictions and filter if they show wear, and inspect the output planet carrier needle bearings, the pump and its drive chain, and the drum bushings. On builds dated December 20, 2021 or earlier, Ford's TSB 22-2281 calls for a new output carrier.

Do I need a relearn after installing the kit?

Yes. Clear the transmission adaptive values with a scan tool and complete the adaptive drive cycle so the PCM learns the new clutch fill times.

• Ford 8F35 Transmission Problems: What the Four Ford Bulletins Actually Say