Radiator failure at auto trasnsmission line cooler housing

[Dukalook Lurker Find all posts View Profile Close Dukalook]

I've got a late 2001 Prado TX diesel auto that has been very reliable for 10 years. Recently however, there was a sudden failure of the radiator at the left side housing for the transmission oil cooling line, resulting in a total loss of rad coolant and major loss of transmission oil. There were no warning signs until the engine warning light illuminated, then I noticed the temperature gauge was off the scale. About 60% of my use of this vehicle over the past 5-6 year has been towing a 2 tonne off-road van, often into fairly remote areas. Luckily I wasn't towing at the time. I had the radiator replaced and towed the van 250km back to Perth without further incident, but this has dented my trust in the Prado's reliabilty. It might or might not be relevant, but about 3 yeas ago I had a Steinbauer PBox chip and a 2.5" exhaust installed to improve towing performance. Has anybody else experienced this problem, and if so, what did you do about it? Am I asking too much of a 90-series Prado to continue using it for long distance heavy-duty towing? Can't afford a new vehicle and I'm reluctant to trade this one in on a 'young' second-hand vehicle unless I absolutely have to. It's got about $12,000 worth of after-market upgrades and accessories that would probably not add much to it's trade-in value.
Cheers,
Dukalook

[Bounder Junior Member Find all posts View Profile Close Bounder]

In my opinion Rads are a consumable item, they should be done every 5-7 years IMHO.
Mine started to give gyp back in 07-08 and I replaced it and never had any bother since.
I would change the combined Rad/trans cooler for separate items though. A rad is a lot cheaper than a new tranny!
There have been reports of the combined unit failing in the UK as well, allowing the ATF to be contaminated with engine coolant, not good.
I would fit a new rad/thermostat/and seperate trans oil cooler, there is a thread on here about how to do it.
They are good for lots of miles, mine has 275k miles on it now = 440k kms

[Steve M Addicted PP Member Find all posts View Profile Close Steve M]

I think you have done well to get 10 years out of it considering probably how hard it would have been working to keep things cool. radiator tanks split on a lot of vehicles and can tell you commodores dont last anywhere near as long. You were extremely lucky you didnt crack the head or do damage to the auto. If I were you I would be going to Toyota and asking for every coolant hose thats on the motor including thermstat and replace the lot and keep the old ones for spares. I wouldnt be buying aftermarket hoses there crap and half the thickness. Toyota ones wont be cheao but already proven they have lasted you 10 years. Trident hoses have been around for a long time but they are no where near the quality of genuine, see for yourself the difference in thickness. Have ou ever replaced radiator cap ?? Could have been the cause by not releasing pressure into overflow bottle ?? Probably not but all contributes. I would also be replacing the flexi transmission lines if not done already and add yourself an external cooler and bypass the radiator cooler, takes a load off your radiator, transmission fluid get incredibly hot. I think your been a bit harsh to the old girl implying shes getting unreliable lol. I would aslo be adding yourself a coolant alarm to let you know in future of any coolant loss or flow before the guage gets to the red. Problem with a lot of factory guages is they dont move till its too late by then major damage normally done. At least with aftermarket coolant alarm it will start screaming at you well before the toyota guage will even move. Dont forget you can also have the guage drop down to cold if you drop al the coolant as well because there is no collant flowing over the sensor so it will not register the temp getting hotter and will infact drop down to cold. Your extremly lucky thats all that you had go wrong at the time. Keep the old girl add a few things to ensure any future issues with coolant you will be on top of, also Id be adding a transmission temp guage so you can keep an eye on things. I know you have done 10 years with no issues but you have to remember not everything last for ever but at least you can be prewarned of anything that may be going to give you issues..........If you dont have the $$ for a new one then keep what you know...Cheers Steve

[glen_ep Addicted PP Member Find all posts View Profile Close glen_ep]

Radiator failure at 10 years is to be expected.

[Dukalook Lurker Find all posts View Profile Close Dukalook]

Radiator failure at 10 years is to be expected.

I agree Glen. It was the mode of failure that set my alarm bells ringing. The RAC bloke who provided roadside assistance - a very experienced mechanic - said he had only seen this specific type of failure once before and that was on a Prado about the same age as mine.

Thanks Steve, Bounder and Glen for your suggestions. I think I'll perservere with the old girl for a while yet and do some of the mods Steve and Bounder suggested.

Graham