New to me auto.

It's usually just a pipe loop (or two) inside the rad, so really shouldn't cause problems. Heavy duty ones tend to be a separate rad.

I'm rather surprised any auto cost that to refurbish. They don't generally suffer major mechanical failure, so just the wearing bits like the clutches and seals need replacing. But a high labour charge for this as it takes time.

But if it got badly overheated through towing etc anything could happen. You'd expect a Landcruiser to be up to that sort of thing.

They certainly couldn't understand why UK etc makers wanted more than 3 speeds on an auto. Even Vauxhall had to go to Asin Warner to get a four speed for the Senator.

The coolant ended up inside the autobox, and buggered up all the valves and hydraulic bits. As soon as he suspected a problem he fitted a new radiator and replaced the fluid but apparently there is a complex procedure to follow to replace the fluid inside the torque converter so the damage got worse.

Vehicle mostly used to commute 50 miles a day to Gatwick Airport, plus towing a 4-wheel race control trailer during the lawn-mower racing season, so not really used for heavy-duty towing, like a massive caravan.

They must have done a good repair because he has done another 150,000 miles since the failure.

ISTR that some brake bands and clutches use water-soluble adhesive, so once the coolant gets in they fall apart.

You'd normally replace a contaminated TC - although some specialists can take them apart and clean. But they're relatively cheap so often more economical to just fit new.

I'd say he was very unlucky to have that happen. Can't say I've heard of it before - and my old SD1 has the transmission oil cooler in the rad.

IMHO, you're more likely to get a 100% successful repair to an auto than a manual box.