A750F Banner Rebuild Kit 2003

If you own a 2003 four-wheel-drive 4Runner, Lexus GX470, LX470 or 100-series Land Cruiser, the five-speed behind your engine is the A750F. These are trucks that tow, wheel and rack up big mileage, and the usual end for the transmission is heat: the clutch packs glaze, the 2-3 shift starts to flare, and a long grade with a trailer brings on a slip you can hear in the engine. This banner rebuild kit is the set of soft parts for overhauling that unit. You get the gaskets and seals, a full set of friction plates, the bonded pistons and a new filter in one package.

What the banner kit does in a 2003 A750F

The F in A750F stands for four-wheel drive. The gear train and clutch layout match the two-wheel-drive A750E, but the rear of the case is built to carry a transfer case, and in these heavy 4x4s the transmission sees more load and more heat than the rear-drive version. Every ratio change is a handoff between clutch packs: one piston releases while another applies. When the friction lining is worn thin or the piston seals have gone hard, the applying pack cannot grip fast enough and the engine flares in the gap. Renew the frictions, pistons and seals together and the handoff gets back to factory timing. In this kit the frictions come from Allomatic and the overhaul set is a Toledo or Precision kit, whichever is current stock at shipping.

Symptoms on a worn A750F

• A shudder or bind-up on the 2-3 shift, or engine flare between third and fourth
• Slipping when towing or climbing in fourth or fifth
• Shuttle shifting or hunting between gears at steady highway speed
• Slow torque converter lockup release, or lockup codes that return after a solenoid is replaced
• Black, burnt-smelling fluid with friction paste on the magnets

How to confirm before you buy

Start with a code scan and a look at the fluid. On these units the solenoid names in the scan tool, the repair manual and the parts catalog do not always match, so look up the code itself before you buy a solenoid that may not be the problem. If the fluid is clean, the complaint may be a TCC solenoid or valve body wear. If it is burnt and the slip is obvious on a road test, the packs need replacing. Our guide to Aisin harsh and delayed shifts walks through the road test, and Aisin overheating prevention explains why towing trucks burn up their clutches.

Fitment

This page covers the 2003 A750F. That year it was used in the four-wheel-drive 4Runner, the Lexus GX470 and LX470, and the 100-series Land Cruiser. Two-wheel-drive 2003 4Runners use the A750E and have their own 2003 A750E banner kit listing. The kit is built for 2003-up A750 units, but internal parts changed in later years, so read the code on the case and match the clutch count in each drum before you start. Give us your year and VIN if you would like a fitment check. All parts for this family are on our Aisin transmission parts page.

Install notes

• Remove the transfer case first. It has its own lubricant, so do not fill it with ATF unless the owner's manual says to.
• Soak the new frictions in Toyota WS ATF before you build the packs, then measure clearance on each one with the steels you are going to run.
• Steels, drums, bushings and planetaries are not in a banner kit. Replace anything heat-marked or worn, or step up to the A750E/A750F master rebuild kit.
• The valve body needs attention on a truck that tows. Worn bores cause flares and TCC problems, and a 2003-2007 A750F shift kit deals with the known wear points.
• Air-check every circuit, fill with WS ATF, set the level hot at the check plug with the engine running, and clear the adaptive values before the first drive.
• Add an auxiliary cooler if the truck pulls a trailer.

Which 2003 vehicles have the A750F?

The four-wheel-drive Toyota 4Runner, Lexus GX470, Lexus LX470 and Toyota Land Cruiser (100 series). The two-wheel-drive 4Runner uses the A750E. The transmission code is printed on the case.

Does this kit fit the A750E as well?

The clutch packs, pistons and main case seals are common to the A750 family, which is why the kit is sold for 2003-up A750E and A750F units. The A750F differs at the rear, where the transfer case bolts on.

What comes in the box?

A Toledo or Precision overhaul gasket and seal set, Allomatic friction plates, bonded pistons and a filter. No steels, drums, bushings, planetaries, solenoids or valve body.

My GX470 flares on the 2-3 shift. Do I need a full rebuild?

A 2-3 flare can come from worn valve body bores before the clutches are damaged. If the fluid is clean, start with the valve body. If it is burnt or full of debris, the frictions need replacing with this kit.

What fluid and setup does it need after the rebuild?

Toyota WS ATF in the transmission, level checked hot at the check plug with the engine running, then an adaptive reset with a scan tool. The transfer case gets its own specified lubricant.

• Aisin Harsh or Delayed Shifts: A Diagnostic Walkthrough
• Aisin Overheating: Why It Happens and How to Prevent It
• ATF Fluid Types Explained: Dexron, Mercon, WS, DW-1, ATF+4 and When to Use Each
• Converter Hub and Pump Bushing Wear: The Loop That Kills Fresh Rebuilds