Transmission Oil Cooler fitted on XR8 II

[blueoval]

I personally think ALL AU's need a separate trans cooler fitted regardless of it's daily uses. They are far more reliable being bypassed from the radiator and they last a lot longer that way. I view it as a bit of insurance.

[AndrewR_AUII]

Originally Posted by rowan194

My AUIII I6 trans overheated today, after spending about 30-40 mins in very slow moving (mostly stopped) traffic, then 5 mins of 80km/hr level road, once I hit some moderate hills it started vibrating under load. I noticed the coolant temp was up too (around "M" rather than "O"), that came down quickly but the trans was still playing up, I guess because the oil holds heat better.

My question is... will a tranny cooler help in this instance, considering that there's no airflow over the stock setup or an aftermarket cooler when the car is stopped?

Would think that once stationary, coolant temp will creep up and fans will turn on..so airflow. Still to fit my cooler (went to do it and saw Radiator is weeping...so waiting for new Rad at the moment). But am thinking about how to fit a temp sensor to Trans cooler so that if Trans temp creeps up, it also turns on fans. Wiring diagram suggests that it is possible. If I get anywhere on this will post it up.

[blueoval]

I have a large aftermarket trans cooler AND a heat exchanger (looks like another smaller but thicker radiator) cooling water in front of my radiator. I have the twin thermo's sucking air in as well as a smaller 10" Davies Craig thermo blowing air into the heat exchanger to help. The temp never gets over the O in normal regardless of temp outside.

Consider getting the radiator flushed and cleaned?

[rowan194]

Originally Posted by blueoval

Consider getting the radiator flushed and cleaned?

Might have to. When I gave my cooling system a bit of TLC a few months ago this is all that came out of the radiator's drain port:



(The brown stuff dripping; the other water on the driveway is rain)

I gave it a good flush and also a couple of days worth of tap water with the heater on high but the drain port was still blocked. This is the first time I've had an overheating problem since I first noticed a slow leak a couple of years back, and the overheating in that case was because the coolant level had dropped. It's spot on right now.

[blueoval]

A high pressure flush from a professional will get out additional blockages. They take the radiator out, remove the tanks and properly clean the cores and unblock all the galleries. Then put it all back together and refill it with fresh coolant. Doesn't cost a massive amount, but if its never been done in its life, it will be very beneficial considering you are getting over heating issues like you are.

A fresh change of thermostat is also worth doing for the cheapness alone while you getting the radiator clean done.

See how that goes first, then if it comes back, look at more expensive areas.

[rowan194]

By the time you've paid labour costs to partially dismantle and clean, plus the new coolant, wouldn't it be worth considering just replacing the rad?

Does the old one have any scrap metal value?

[blueoval]

Doubt it. If you are intending on replacing the rad though, don't just get ordinary replacement. Go copper core radiator. that way it shouldn't rust and corrode. A bit more than regular but lasts heaps longer.