4L60E Heavy Duty 3-4 Clutch Pack Kit with Filter and Pan Gasket

If your Silverado, Sierra, Tahoe, Yukon, Suburban, Avalanche, S10, Blazer, Astro or Hummer H3 flares between third and fourth, slips in overdrive on a hill, or has dropped third and fourth gear completely, the 3-4 clutch is the first thing a 4L60E rebuilder looks at. This kit restacks that clutch and finishes the service in one order: 9 friction plates, 10 steel plates, the 3-4 apply plate and its retaining snap ring, plus a new transmission filter and oil pan gasket. It cross-references GM 24208465, 24208576, 24217453, 24208148, 24208813 and 24208149 and the A74100CPPK pack, and it covers both the 4L60E and the 4L65E.

What the 3-4 clutch does in a 4L60E

The 3-4 clutch lives in the input housing at the front of the gear train. It applies on the 2-3 shift and stays on through fourth, so every mile a truck cruises in overdrive is a mile this pack is holding engine torque. Space in the drum is tight. Sonnax notes that the original 700-R4 and 4L60E packs ran five or six frictions, while the later 4L65E and 4L70E went to seven, and that the factory backing plate flexes under apply and lets heat build unevenly through the stack. That is why burnt 3-4 clutches are the signature 4L60E failure, especially behind a towed trailer, a larger tire or a modified engine. A heavier pack spreads the load across more friction surface so each plate runs cooler.

Symptoms of a burnt 3-4 pack

• Engine RPM flares on the 3-4 upshift before fourth grabs
• RPM climbs in overdrive while road speed stays the same, worst when towing or climbing
• Third and fourth are gone while first, second and reverse still pull
• Dark fluid with a burnt smell and black friction material in the pan
• Code P0741 or a slipping lockup feel can show up at the same time if valve body bore wear is feeding the problem

No third and fourth can also mean stripped reaction sun shell splines, another common 4L60E break, so confirm which failure you have on teardown before you order.

How to confirm it before you buy

Pull the pan first. Heavy black friction debris and a burnt smell point to the 3-4 pack; shiny metal and a broken sun shell point elsewhere. Sonnax traces most 3-4 slipping to low line pressure and third gear oil leaks rather than the clutch itself, so a new pack only lasts if you find the leak. Air check the loaded input drum, look for a cracked 3-4 piston, check the input housing check ball and the Teflon sealing rings on the input shaft, and vacuum test the pump boost valve. Our 4L60E 3-4 clutch failure diagnosis guide walks through that checklist, and the 3-4 friction count and upgrade guide explains how plate counts and thicknesses change by housing.

Fitment

Listed for 4L60E and 4L65E units in 1994-2007 Silverado and Sierra 1500, 1995-2006 Tahoe, Yukon, Suburban and Yukon XL 1500, 2002-2006 Avalanche 1500, 1995-2005 Blazer and Jimmy, 1994-2004 S10, 1998-2002 Camaro, 1994-1999 Astro and Safari, 2002-2006 Escalade and ESV, 2004-2006 Yukon Denali, 2006-2010 Hummer H3 and 1998-2000 Hombre. Input housings changed over these years, so count the plates you pull out and compare plate thickness against the new ones before assembly. A nine-friction stack only works if the plates and your housing give the right total height. If you are unsure, send the year and VIN and we will check it. Everything else for this unit is on our 4L60E parts page.

Install notes

• Soak the frictions in clean ATF for at least 30 minutes. Refill a 4L60E or 4L65E with Dexron VI.
• Stack friction and steel alternately, install the apply plate and snap ring, then measure clearance with a feeler gauge under the snap ring. Too tight drags and glazes the pack, too loose slips on the shift.
• Use new load release springs. Sonnax warns never to leave them out, because the light factory return spring needs the help to stop drag.
• Air check the drum and watch the piston apply and release cleanly before it goes back in the case.
• Install the new filter and pan gasket, torque the pan bolts evenly, then fill and check level hot.
• If the pump or seals caused the burnup, fix them now: a bonded 3-4, forward and overrun piston set replaces cracked pistons, and the master solenoid kit with EPC addresses the pressure control wear that drops line pressure.

The kit ships at about 4.9 lb. Drive gently for the first few hundred miles so the new frictions bed in before you tow.

Does this 3-4 kit fit both the 4L60E and the 4L65E?

Yes. It is listed for 4L60E and 4L65E applications from 1994 to 2010, including Silverado, Sierra, Tahoe, Yukon, Suburban, Avalanche, S10, Blazer, Camaro, Astro, Escalade and Hummer H3. Check plate count and clearance against your housing on assembly.

What comes in the box?

Nine friction plates, ten steel plates, the 3-4 apply plate, the retaining snap ring, a transmission filter and an oil pan gasket. Pistons, seals and load release springs are not included.

Which GM numbers does it replace?

It cross-references GM 24208465, 24208576, 24217453, 24208148, 24208813 and 24208149, plus the A74100CPPK pack.

What fluid should I refill with?

Dexron VI ATF. Soak the new frictions in the same fluid for at least 30 minutes before assembly.

Why did my 3-4 clutch burn in the first place?

Usually low line pressure or a third gear oil leak, such as a cracked 3-4 piston, worn input shaft sealing rings, a leaking check ball or a worn pump boost valve. Backing plate flex is another leading cause. Find and fix the leak or the new pack will burn too.

Will this fix no third and fourth gear?

It will if the 3-4 frictions are burnt. If the reaction sun shell splines are stripped, you need a sun shell instead. Inspect both on teardown.

• 4L60E 3-4 Clutch Pack Failure: Diagnosis and Upgrade Options
• 4L60E 3-4 Clutch Pack: Friction Count and Upgrade Options
• 4L60E Common Problems, Symptoms, and What to Actually Do About Them
• 4L60E Shift Solenoid Symptoms, Testing and Replacement