auto box overheating

[Dai]

ok here goes

My old box boiled the transmission fluid twice ...destroying the box, and at long last have been able to track down a replacment. Now what I need from you peeps is clues as to what would have caused the the old box to get so hot (it had melted the alloy ) as I do not want this one to go the same way.

Itis '96 3.00 ltr 1KZ

I have had the rad rebuilt (but not the oil cooler)

all answers in simple english as I dont do cars and will have to pass it on to the chap who fixing it for me

cheers
Dai

[That Ruddy Squirrel]

Silly questions - have you been towing a heavy load ?, or was the fluid level low ?

I have a late 93 1kzte 3.0 Litre 2nd gen.


Trev

ok here goes

My old box boiled the transmission fluid twice ...destroying the box, and at long last have been able to track down a replacment. Now what I need from you peeps is clues as to what would have caused the the old box to get so hot (it had melted the alloy ) as I do not want this one to go the same way.

Itis '96 3.00 ltr 1KZ

I have had the rad rebuilt (but not the oil cooler)

all answers in simple english as I dont do cars and will have to pass it on to the chap who fixing it for me

cheers
Dai

[Chillitt]

if so was it on an uphill bit she blew?

[Dog_Book]

Could be the oil cooler not working, i have added a second cooler to mine.

[usafric]

I have the same Surf, and if I am towing and go above 75-80 MPH, the engine gets really hot, I read it is something to do with the location of the trans cooler, at the bottom of the rad. Fitting a cooler BEFORE the rad should cool it down enough so it wont heat up the engine coolant. That is what I gather, and am going to do it myself. Good luck...

[AndyLala]

When I got my rad rebuilt ...


Oil cooler in the base of the standard rad is a series of square tubes bonded together sitting in the lower header tank. The coolant flows over this to reduce the temperature of the Auto box fluid, at least that is the theory...

These 'standard' coolers, I am told, delaminate. Its the same rad setup that the Metro Cabs use... They usually add a 13 row external cooler to boost the cooling capacity. Incidentally these Square Metro cabs are all hilux 2.8 Diesel running gear... Serck replace these as a matter of course when they recore and rebuild the rads for these taxi cabs every two to three years.

Usual comments which have come from the Aus site, commented on a number of times here... is to reduce the size of the cooler that sits in the rad to clear the lower outlet of the rad. These guys use a Heavy Duty Aus Toyota cooler... A little difficult here to get hold of... So a little lateral thought.

I sat with the guys at Serck in Southall and went through what would fit and clear the lower outlet. We moved the drain plug from the passenger side to the driver side, and binned the old one...

Mercedes 190 auto oil cooler... short enough, single tube, double wall sits nicely in the lower header tank.

We also went to four cores, triumph stag upgrade style core broad enough not to get crap caught in it, and offset it forward about 10mm... just clears the fan. Adds about an additional litre of coolant to the system.

I still have a 13 row additional cooler to add and the next time I treat the auto box to a flush, that will get added to the system.

HTH, andyL