Aux ATF cooler configuration

[Andy]

Up as high as 130 but then I took measures to cool things down, ie low box.
The temps would have kept on rising otherwise, (in fact did hit just over 140 once), but the light on the dash still didnt come on, I did think about waiting for that to happen, just to check it worked, but thought better of it & relied on the gauge!!
This is also when I did my 180degree turn experiment to drive into the wind, and that helped a lot

Andy

 

[Jon Wildsmith]

I don't know which way round the OEM cooler is Julian, the pipe routing is hard to follow without taking the front bash plate off. I'm not surprised Andy saw no difference though because I don't think the in radiator 'cooler' is doing a great deal other than making sure the ATF is up to operating temps on a cold day.

I have a 10" fan on my aux cooler which is switched by my Arduino gadget which is currently set to switch on at 90c. I know I bang on about it a bit sometimes but without a temp gauge you have no idea what's going on until it's too late and damage of some degree is already being done.

 

[pugwash]

If you aren't sure what to go for then buy an Oilstat
http://www.thinkauto.com/oilstats.htm
http://www.thinkauto.com/acatalog/On_li ... ts_30.html

this opens an extra circuit at 80 or 95degrees- you could plumb it so that the engine warms the box until it gets to 80 then after that it passes through the aux ATF cooler, or the other way round, so that at 95 degrees it add the aux cooler in.

You can also get custom temperature stats made.

Its generally accepted wisdom that every 10 or so degrees above 80c halves the life of auto box oil (and by life i means its effective ability to maintain seal structure, prevent varnish on clutches, and maintain fluid stability when subjected to heat, and indeed its handling on heat without seperating further into short chain carbon structures and water!).

http://www.roscommonequipmentcenter.com ... s/nn15.pdf is a very informative guide on how to choose a cooler, and the rational on where to put it, as well as some background on temperatures of auto boxes.

In reality keeping the auto box cooler than the engine is a good thing, but keeping it at less than 100c is pretty much essential.

If the gearbox temp light comes on then you've really cooked the box, and you must let it cool- one of the best ways is to put the truck in low first and drive round with very low loads on the box- the gearbox will keep pumping oil round and the movement of the box helps to stop localised overheating.

 

[Andrew Prince]

Thanks, Jim! Some great info there - will look at the oilstat set-up!

Cheers,

 

[vrecha]

Very useful topic, I'm also interested in keeping my autobox alive as long as possible. Didn't have any additional coolers installed, but will install one soon.

So far haven't had any issues with the overheating, although I have done quite some sand driving, even continuous for few hours at unpleasing ambient temperatures (>45°C).

My receipt for sparing the autobox that proved successful so far is: do have some "mechanical empathy" (term courtesy of Tom Sheppard).
I often drive barefooted and I definitively drive barefooted when I'm anticipating hard work for the auto transmission unit (sand, long steep climbs ...). That way I can feel with my left foot when the heat from the autobox starts cumulating. When the left foot starts to feel uncomfortable because of the present heat, i stop or apply other possible measures to cool the machinery down.
It's a funny way to do it, but it works.

But as said, I am intending to install the cooler and the ATF temp gauge soon. And as we are discussing this, any idea where is the best to install the temp sensor? Some say measuring the temp of the bulk oil in oil pan is the way to go, others install the sensor inline somewhere ... Any idea where would be best in a 80 with an explanation why?

 

[Jon Wildsmith]

And as we are discussing this, any idea where is the best to install the temp sensor? Some say measuring the temp of the bulk oil in oil pan is the way to go, others install the sensor inline somewhere ... Any idea where would be best in a 80 with an explanation why?

The Wholesale Automatics solution is to supply a new outlet union with an extra hole drilled and tapped with a VDO sender fitted into it. They've managed to source a VDO sender with a very short sensor protrusion which I've not seen for sale anywhere. My solution (on my 100) was to remove the OEM sender and fit a VDO sender using an adapter and when I looked at the 80 series box and union under my bench I thought you could do the same on an 80 but make sure you get a matching sender and gauge. I've lost the OEM warning light functionality doing it this way but I don't need it. Measuring the temp where it comes out the box lets you see the temps in the TC near enough, where it's hottest. Using the pan temp will have a delayed responce and never show you peak temps that are being generated inside the TC.

Put time and effort into fitting a temp guage before you spend it on a cooler, if you can see what the temp is you can respond to rising temps and keep them under control. Then fit an aux cooler so you are less likely to have to deal with high temps An aux cooler alone won't always keep you out of trouble but an intelligent driver with a guage should do

 

[pugwash]

FWIW i have a kit to install a temp sender in a sump (it was for another project)

basically you drill a hole in the sump, then this kit bolts to both sides of the hole, sealing it completely and then you stick the sender in the middle.

It won't tell you if the temperature of the box is spiking (you really need one near the outlet of the autobox), but it will tell you very accurately what the general temp of the box is- perhaps more relevant for overlanding?

 

[frank rabbets]

Hi Andrew

I am ignorant of most of all this and have not read ALL the way through the thread.I hope you will forgive me if my comments are totally irrelevant. I have prepared a couple of race cars where the manual gearbox needs cooling. This is done by fitting a thermostat and a cooler somewhere near an external source of air and having an electric fan. By unfortunate experience I have found 3 essential rules

1 Have 2 side by side fans with 2 separate relays.

2 Have 2 thermostats in parrallel.

3 Have an accurate temperature gauge and warning buzzer.

This approach may save you worrying about how the original cooling system will interact with another. All you need is a rad and where to put it. You can have one made cheaply to virtually to any shape or size. Sorry if I'm talking balls but sometimes an uneducated approach works.

Frank

 

[Dave2000]

I think this was discussed on here on another uk forum? I always fit aux coolers before the OE rad one. The reason for this is simple, my clients can be running on the beach in Southern Spain with 40+ degrees and this helps take the load off the engine radiator and of course the oil is nice and cool. The following day they could be in Northern Spain up a mountain at a ski resort in minus bloody cold degrees so the engine radiator helps bring the temperature of the auto oil UP to temperature.

So before the OE rad is a win win situation here, however in the UK?

regards

Dave

 

[Rob]

Just to add a spanner in the works. Can't remember which way round we decided on but the Volvo auxiliary ATF cooler (genuine Volvo modification which comes with fitting instructions ) is plumbed in after the rad, and I can assure you it works well.

 

[Bat21]

.... is plumbed in after the rad, and I can assure you it works well.

The one I fitted to my 80 is plumbed in after the rad and yes it works well.

I am convinced the one in the rad actually increases the temp of the ATF.... so fitting an auxiliary one before wouldn't be effective in cooling the ATF.

If anyone is worrying about it over cooling in the winter months, just get the Mrs to knit a nice thick woolly jumper to slip over the auxiliary rad during the cold

 

[Matt Wright]

A very good informative post Mr P.
It looks to me from reading that there's a prevention (temp gauge) and a cure (extra cooler)

My field experience from the Africa trip was that an 80, FULLY loaded with 4 passengers and a full roof rack frequently had the ATF light coming on in areas of high altitude and where there were lots of hills / mountains. This mainly being in Ethiopia.. They're called the highlands for a reason! Due to the terrain, it's slow going which adds to less air moving over the radiators too

I have zero empirical info, but

1. The ATF light came like clockwork every time we approached a long climb with zero momentum

2. Very importantly on a long trip, you either have to take your own ATF to do oil changes or use the local stuff. I only ever found 1 brand of TOTAL ATF fluid anywhere till we were waaay passed the trouble areas! Makes you think about our fancy equipment etc - where in the places it's not available, everything seems to work out..!? Not saying you shouldn't use fancy stuff, just that after a certain distance you have to change all the uprated oils etc and there's none to be found..

My 5c, prevention is always easier and cheaper than cure, so the temp sensor sounds like a great start. I wish I'd had one (cause I used my toe as a temp sensor on a patch where the carpet was missing!)

 

[Rob]

My 5c, prevention is always easier and cheaper than cure, so the temp sensor sounds like a great start. I wish I'd had one (cause I used my toe as a temp sensor on a patch where the carpet was missing!)

As a saffa you clearly don't need a temp sensor, a hole in the carpet is no use for the rest of us

 

[Bat21]

.... My field experience from the Africa trip was that an 80, FULLY loaded with 4 passengers and a full roof rack frequently had the ATF light coming on in areas of high altitude and where there were lots of hills / mountains.

Matt, I have mentioned this in another thread on the subject but there's no harm mentioning it again.... get yourself a bottle of this... your ATF will love you for it it came highly recomened by a friend who builds automatic transmissions for a living.

It prevents the ATF getting to unwanted temperatures

 

[Andrew Prince]

get yourself a bottle of this... your ATF will love you for it it came highly recomened by a friend who builds automatic transmissions for a living.
It prevents the ATF getting to unwanted temperatures

Any idea how it prevents the heat building up, Paul?

 

[Bat21]

Any idea how it prevents the heat building up, Paul?

From what I remember my mate saying, it increases the oxidation point of the dextron ATF significantly and so lowers the operating temp of the transmission.

My ATF light never came on once on this years Morocco trip. I did fit an oil cooler too but the guy who recommended the Lube Guard said it alone would be enough to keep the temps down.

 

[Rob]

From what I remember my mate saying, it increases the oxidation point of the dextron ATF significantly and so lowers the operating temp of the transmission.

I'm no chemical engineer but this does not sound right

 

[Bat21]

I'm no chemical engineer but this does not sound right

Neither am I Rob, but my mate has been building auto trans for years so I took his word for it.... he mentioned Sperm Whale oil and I thought he was pulling my plonker but see the two reviews below and it seems he was right:-

Product Description Lubegard Red Universal Automatic Transmission Fluid Protectant

The number one product used in the professional transmission rebuild industry and the only product of its kind to be used and approved by major automobile manufacturers -- SAAB Peugeot BMW and Volvo to name a few. Reduces operating temperature allowing transmissions to perform more efficiently. Increases thermal and oxidative stability of ATF for stop and go driving heavy loads and towing. Reduces transmission wear extends fluid and transmission life. Maximizes over all transmission performance. Helps reduce comeback and warranty problems for shops and mechanics. Insures proper and smooth shifts. Prevents clutch chatter and torque converter shudder. Eliminates objectionable noise (squawks) during shifts. Keeps valves free. Frees stuck valves in valve bodies. Prevents hung governors. Modifies harsh shifts and makes them quicker in duration. Can be used with all ATFs: OEM Synthetic or Mineral-Oil Based. Contains LXE (synthetic esters and synthetics).

Most Helpful Customer Reviews
Lubegard "RED" is a rare "no-brainer" for almost EVERY Transmission New & Old!
Lubegard RED a true "No Brainer for Basically Every Tranny!" From a brand new Porsche to a 10-year old Chevy. There are very few "ADDITIVES" that many mechanics that really know their stuff will recommend. *THIS IS THE EXCEPTION!! Especially transmission specialist! 1oz. of Lubegard RED added to each Quart of your transmission fluid can short-term & long-term perform miracles on the life and health of your transmission. Yes "SYNTHETIC SPERM WHALE OIL" which is the main ingredient in here (and since the 1970s "Real Sperm Whale Oil" had to stop being used in trannys because of the Endangered Species Act) Trannys failed left and right as a result. This stuff does everything it says it does and for £16..... READ UP ON IT YOURSELF (http://www.lubegard.com)& ASK NOT JUST A Mechanic, BUT an EXPERIENCED one that Specializes in Transmissions and see what they have to say!

 

[Rob]

Increases thermal and oxidative stability of ATF for stop and go driving heavy loads and towing.

This makes a little more sense, I'll let someone else make sense of it.

 

[Matt Wright]

.... My field experience from the Africa trip was that an 80, FULLY loaded with 4 passengers and a full roof rack frequently had the ATF light coming on in areas of high altitude and where there were lots of hills / mountains.

Matt, I have mentioned this in another thread on the subject but there's no harm mentioning it again.... get yourself a bottle of this... your ATF will love you for it it came highly recomened by a friend who builds automatic transmissions for a living.

It prevents the ATF getting to unwanted temperatures

Thanks Paul! My toe sustained permanent burn marks so I've ordered 2, one for each truck. Hard to go wrong for £9!?!?
If it works as well as you say it does (and I don't doubt that it does), I'd suggest taking enough for 1 per ATF change on long trips., this plus "whatever's available en route" sounds like a good combo