80 series 1997 Automatic transmission AT overheating

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Dec 18, 2007
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Hi,
I have a 1997 turbo-diesel 80 series which was modified for overlanding. ( Engine is stock except a bigger radiator). The car weight is about 3500 kg ( appx. 8000 lb) with all liquids an 2 persons. The AT gets often overheated on HIGH gear and we are forced to drive on LOW gear to avoid overheating ( the diff are not engaged). This is slow, noisy and fuel consuming. The overweight is probably the main problem but we cannot change it).
We added an additional radiator/ cooler ( from wholesale automatic in Australia and a gauge to measure temp.) The cooler helps but not enough.
We consider
1. Changing the gear ratio on HIGH so it has more torque and sacrifice final max speed and overall run the engine at higher rpm. Anyone can comment on this solution.
2. Replacing the pan with an after market deep pan. There are many but could not find a vendor for the 80 series. Maybe someone knows. Made of Al with fins will be the best.
3.Spraying water remotly from the cabin on the cooler fins.Any comment on this?
4. Any other solution will be more then welcome
Thanks,
Israel
 
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Which transmission is in your diesel 80 series (A442F)?

Have you modifield/replaced the valve body or torque convertor?

You could send an email to Wholesale Automatics in Australia discussing your situation. They have various options for improved torque convertors (where much of the heat is generated) and also valve bodies with improved performance.


Here's some links:



 
Last edited:
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The issue is in high gear you're not fast enough to keep the converter locked up and this creates heat. I would talk to wholesale about a valve body. This will allow lock up in third gear.

8000lbs is a lot too.

I had issues with trans temps in the past. I'm curious to see how my monster trans cooler does off road.

Did you bypass the radiator?
 
Last edited:

Squash

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Whenever the tranny is hunting for gears heat is generated, do yourself a favour and drop into third keeping the rpms up until conditions warrant 4th gear.
If you are in sand or snow heating is a big issue so pick the proper gear often this is when I use Low.
I use a transmission temp gauge and can assure you heat builds up rapidly
 
Joined
Dec 18, 2007
Messages
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Which transmission is in your diesel 80 series (A442F)?

Have you modifield/replaced the valve body or torque convertor?

You could send an email to Wholesale Automatics in Australia discussing your situation. They have various options for improved torque convertors (where much of the heat is generated) and also valve bodies with improved performance.


Here's some links:



 
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Dec 18, 2007
Messages
29
Hi, Tks. Yes it is a 452F. I am sorry for the late response. We were travelling backroads in Colombia and Ecuador and usually not have Internet. Yes, I am familiar with Wholesale but apparently all the renovation will not reduce temp. but I am going to ask again if a complete renovation will solve the problem
 
Joined
Dec 18, 2007
Messages
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The issue is in high gear you're not fast enough to keep the converter locked up and this creates heat. I would talk to wholesale about a valve body. This will allow lock up in third gear.

8000lbs is a lot too.

I had issues with trans temps in the past. I'm curious to see how my monster trans cooler does off road.

Did you bypass the radiator?
Hi, Tks. No i did not by pass the radiator. See more info inmy response tothe former person that answeref
 
Joined
Dec 18, 2007
Messages
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Whenever the tranny is hunting for gears heat is generated, do yourself a favour and drop into third keeping the rpms up until conditions warrant 4th gear.
If you are in sand or snow heating is a big issue so pick the proper gear often this is when I use Low.
I use a transmission temp gauge and can assure you heat builds up rapidly
Hi, Tks. Yes I am aware of these issues
 
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Bypass the radiator.

A rebuild is not going to fix it.
3 ways to remove heat from a transmission

Larger cooler/cooling fans

More fluid capacity (larger pan)

Reduce slippage. So better converter that slips less and locks up more aggressively.
Valve body that reduces slippage between shifts.
Driving at a speed that allows the converter to lock up.
 
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Put on very small wheels and tires.

6a2060fa-6cb2-4cf6-9471-ae90b674e5a3-jpeg.1598317


(Credit to @bugsnbikes for that picture of his daily driver)
 

Broski

I love Wheelin my 80
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