4L30E master rebuild kit with steels, seals, rubber rings and gaskets for 1990-2004 Isuzu Rodeo, Trooper, Amigo, Axiom, Honda Passport and BMW Z3.
Owners of an Isuzu Rodeo, Trooper, Amigo, Axiom or VehiCROSS, or the Honda Passport built alongside the Rodeo, usually find this kit after the four-speed automatic starts slipping into 3rd and 4th, flares on the 2-3 shift, or loses Reverse. That transmission is the GM 4L30E, and this master rebuild kit carries the steel plates, seals, rubber rings and gasket set needed to reseal it during a full overhaul. The same unit was also used in the Cadillac Catera and BMW Z3, which are on the listing too.
The 4L30E is a compact rear-drive four-speed that GM built in Strasbourg, France, rated for about 350 Nm of engine torque. Isuzu trucks use the Type B gear set, with a 2.86 first gear and 1.62 second, deeper than the 2.40 first in the BMW and Opel Type A, which suits a heavier SUV but also loads the clutches harder when the truck tows or climbs. Each clutch is applied by a piston sealed with lip or lathe-cut seals, and every circuit passes through sealing rings on the shafts and support. Once those rubber parts harden and the steels heat-check, apply pressure leaks away and the unit slips, flares or stops moving in one range. This kit renews the steels and the full set of seals, rings and gaskets so each circuit holds pressure again.
Reverse trouble on a 4L30E is not always the clutch. Transmission Digest's TASC Force explains that a 4L30E slipping or neutraling in Reverse when cold can come from a leaking TCC solenoid feeding signal oil to the reverse-lockout valve, and that a solenoid with its screen missing is a common find. Check fluid condition, scan for codes, and run line pressure checks with our line pressure testing guide. If Reverse is weak and the unit has never been apart, air-check the reverse clutch through the case; a loud leak points straight at the seals this kit replaces. Our flare versus slip article helps you read the forward-gear complaints.
Listed fitment is the Isuzu Rodeo 1991-2004, Trooper 1990-1992, Amigo 1999-2000, Axiom 2002-2004 and VehiCROSS 1999-2001, the Honda Passport 1994-2002, the Cadillac Catera 1998-2001 and the BMW Z3 1996-2000. The core of the 4L30E is shared, but the adapter case, center support and the spacer plate between them differ by manufacturer and do not interchange, so the gasket you need at that joint depends on the make. Read the tag on the case and compare your old gaskets with the kit, or send us the year and VIN and we will confirm. The other 4L30E overhaul parts are in our rebuild kits collection.
This kit is built around steels and sealing parts. If the frictions or the band are burnt, add the 4L30E friction, band and filter kit so every pack is renewed. Inspect the reverse piston bore in the center support; TASC Force notes that a rough inner seal surface wears the new lathe-cut seal and causes no-reverse after an overhaul, so dress that surface if it feels like a record groove. Set clutch clearances to spec, check endplay as covered in our thrust washer and endplay guide, and fit a new 4L30E TCC solenoid if yours has lost its screen. Refill with a Dexron III-compatible fluid such as Dexron VI and check the level hot.
| Transmission | GM 4L30E 4-speed RWD |
| Includes | Steel plates, seals, rubber rings, gaskets |
| Listed fitment | 1990-2004 Isuzu Rodeo, Trooper, Amigo, Axiom; Honda Passport; Cadillac Catera; BMW Z3 |
The listing names steel plates, seals, rubber rings and gaskets. If your frictions or band are burnt, pair it with our 4L30E friction, band and filter kit so every clutch pack is renewed.
Yes, the 1994-2002 Honda Passport is listed. It uses the same 4L30E as the Isuzu Rodeo. Send us the year and VIN if you want us to confirm.
The core is shared, but Isuzu trucks use the Type B gear ratios and the adapter case, center support and spacer plate differ by manufacturer. Match the gaskets at that joint to your own unit.
Common causes are mixed center support or adapter parts from another make, or a reverse clutch inner seal worn by a rough piston bore. A leaking TCC solenoid can also cause Reverse to slip when cold.
Use a Dexron III-compatible ATF. Dexron VI is the current GM fluid that covers older Dexron applications. Check the level hot after the rebuild.
