Lexus GS300 Stuck in Gear 4 and Slipping: How We Overhauled the Gearbox and Replaced the Torque Converter

The owner brought in a Lexus GS300 with the gear indicator stuck showing gear 4. The gearbox was slipping, so the car was not shifting the way it should. A gearbox that holds one gear or slips is not something to keep driving on. The longer it runs like that, the more the inside wears.

The ask was simple. Find out why the gearbox was stuck and slipping, and fix it so the car drives normally again. The owner wanted a clear answer and a firm price before any work started, not a guess.

We checked the car and the gearbox rather than guessing from the symptom alone. The gear indicator stuck at gear 4 and the slipping both pointed inside the gearbox, not to a simple sensor.

Once we opened the gearbox, the picture was clear. The clutch packs were worn and had started to slip, which is why the car was not holding its gears. The torque converter had also failed. Together those explained the stuck indicator and the slipping the owner felt on the road.

We walked the owner through what we found and quoted firmly before any work began, so there were no surprises later.

We did the job properly rather than patch it and hope.

• Removed the gearbox and stripped it down completely.
• Overhauled it with all the internal consumables, including the worn clutch packs, seals and gaskets.
• Replaced the failed torque converter with an OEM-grade part.
• Refilled with the correct ATF and test ran the car to confirm clean shifts.

We kept the owner updated through the job. Because a full overhaul means stripping the gearbox, replacing the worn parts and testing it after, the work took the time it needed. We did not rush it, since a rushed gearbox that has to come out again helps no one. The car shifts properly again, and the overhaul carries a 2 year / 40,000km warranty.

On this GS300 the torque converter came to about $950 and the ATF fill about $200; the overhaul portion is quoted after the strip-down shows what is worn inside. The work covered the full overhaul, the worn clutch packs and consumables, and a new torque converter, all backed by a 2 year / 40,000km warranty.

What moves the price is what we find once the gearbox is open. A gearbox caught early, before more parts are damaged, sits at the lower end. One that has been slipping for a long time can need more parts replaced. This is why we open the gearbox and check first, then quote for exactly what is worn rather than guessing high.

This Lexus GS300 (Gearbox overhaul and torque converter replacement) was handled at 1 Car Service, an independent workshop in Sin Ming AutoCity, Singapore. The work is backed by our 2-year, 40,000km warranty. We hold a 4.9★ rating from 1,775+ Google reviews.