Topic: Transmission cooler on a car?

[jwalters]

Hello, I pull a single motorcycle behind my '97 Chevy Malibu.  Mostly for around town, but a few day trips will see the car and trailer on the highway for 3 or 4 hours at a time.  Would I be wasting my time and money putting a transmission cooler on my car.  I've heard that any front wheel drive vehicle can benefit from one, b/c the automatic transmission build up a lot of heat.  I thought I would see what others have to say.  For the record, total weight of bike + trailer would be less than a 1000lbs.
Thanks!

[heffay]

not sure of yours but many cars route a tranny fluid line thru the radiator straight from the factory... u sure yours doesnt do that allready?

[jwalters]

Not sure, I'll take a look.  Thanks for the tip.
-j

[heffay]

course, my main reference was my old j20 jeep... and being a 3/4 ton truck we can all figure out why it might need a cooler tranny, especially being full time 4x4

[clarkjh]

my civic has a secound set of hoses routed through the rad, I think its for the trans-axle.

James

[Gordon]

I would think that with a relatively small trailer weight you'll be fine, as long as you're not planning on crossing any major mountain ranges.

[Steve F]

I pulled a pop-up camper with my '89 S-10 Blazer 4.3 V6, loaded to the brim with stuff and 4 people throught the Arizona desert during the daytime.  Outside temp was a blistering 113F, AC running, and all the while it had just the standard "through the radiator" trans lines.  Upon reaching San Diego, I checked the trans fluid for signs of burning or other problems, and everything was fine.  A 1000 lb. trailer isn't all that bad, especially if you're not driving like a bat outta hell, and keep your foot out of it.  You'll be fine.

[csendker]

I pulled a small pop-up with a '95 Caravan.  It didn't have the auxiliary cooler built-in.  I added one after frying the first tranny, and overheating the second.  Then I sold it.  It was only a hundred or so bucks to add it, so if you don't have it built in, I'd recommend it as it's a LOT cheaper than a new tranny.

[TwoTired]

As others have mentioned, your auto trans probably already has a cooler built into the radiator.  So, do check and verify.  If so, then your car's engine temp gauge will give you the information needed to determine if you need and auxiliary cooler.  An over heating trans will impart that heat into the engine's cooling system.  When the heat goes beyond the capacity of the radiator, the engine temp climbs.  This is your que to back off the power and reduce speed until the temp goes back to normal.  It also tells you that you need an auxiliary cooler for the trans which should be placed in the feed line going to the radiator to "pre-cool" the fluid going into the radiator.

I had to install a trans cooler on my truck when I was towing a trailer.  It was okay on the flats, but in the mountains, the temp gauge would only allow speeds of 35-40 going up hill, or the engine temp would go up out of sight.   The trans cooler added 20-30 mph to my "climb speed" depending on altitude.  Before the cooler, I did toast the trans fluid once, while I learned what the engine temp gauge was telling me.  But, not since.

If you don't have a temp gauge on your engine, get one if you are going to tow trailers and/or drive in mountainous territory.

Cheers,

[Jonesy]

As others have mentioned, your auto trans probably already has a cooler built into the radiator. So, do check and verify. If so, then your car's engine temp gauge will give you the information needed to determine if you need and auxiliary cooler. An over heating trans will impart that heat into the engine's cooling system. When the heat goes beyond the capacity of the radiator, the engine temp climbs. This is your que to back off the power and reduce speed until the temp goes back to normal. It also tells you that you need an auxiliary cooler for the trans which should be placed in the feed line going to the radiator to "pre-cool" the fluid going into the radiator.

Not always. The trans coolers on some vehicles (mostly trucks) are in the form of a smaller radiator in front of the engine coolant radiator, or on some larger cars (like the newer Crown Vic) they are part of the radiator, but have separate fin/tube heat exchangers along the bottom of the assembly and sit directly in the airstream, as opposed to the common shell/tube heat exchanger found in many cars to cool the tranny.

In a lot of cars, the endtank on the radiator contains a coil or ribbed tube that carries the trans fluid. This heat exchanger is on the cool side of the radiator (the coolant reaching this end has already been cooled by the airstream). Even with the bit of extra heat added back into the coolant, the thermostat would likely just open a bit more. This, along with the varying locations of the different temp sensors in the engine (one for the dash cluster, another for the ECM to determine if the engine is hot enought to go into closed-loop emission feedback mode) in my mind makes it a toss-up and can't always warn of trans heating via the dash gauge.

So, check to see if you have a cooler already in place and monitor the fluid periodically. The GM pickups would get so hot at times they would pop the trans dipstick out so hard it would dent the hood! They put a locking cap on them to fix this, and now condensation build up in the filler neck and rusts the insides. Then the rust is carried into the trans when you pour in fresh oil. Real smart design...

[csendker]

The one added to my old Caravan was a small 'radiator' - fin-type job mounted directly on, and in front of the bottom of the primary radiator.  Or maybe just below it, can't properly remember.

[dusterdude]

The one added to my old Caravan was a small 'radiator' - fin-type job mounted directly on, and in front of the bottom of the primary radiator.  Or maybe just below it, can't properly remember.

your problems werent due to lack of a cooler,that issue is/was a chrysler junk ass transmission issue,especially if it was overdrive.

[csendker]

Can't argue that point.  The whole damn thing fell apart at 60K.  Tranny fried (maybe my fault w/towing), the floor leaked, the damn seat broke - try driving and the seat back just drops to the floor.  All sorts of issues.  Major POS.

[ProTeal55]

Any vechile can benefit from a trans. cooler. The longer the fluid is out of the transmission, and has a
chance to cool off, the better. I have always put a larger cooler on all of my cars, and have yet to
have even a hint of transmission problems. Another cheap and easy way to get a cooler fluid is to run long lines
to and from the cooler. It increases your fluid capicity - and allows the fluid to cool even more.

If I were going to tow with a Malibu , I would DEF. invest a few bucks on a decent cooler.

P.S.

Almost 90% of modern day trans. temp gauges in modern cars are worthless. They are more of an "Idiot-light" than an
actuall gauge. Once the gauge reads hot, the damage to the transmission is allready done..

[Dave Wyatt]

Along with the auxillary cooler, do not tow in overdrive.  OD creates more heat due to the indirect routing of power through the transmission (yes, even on an automatic.)  Tow in drive (3rd) and you will be OK.

Towing is why I bought a truck with a manual transmission.  It does not kill itself.

[heffay]

for once... i agree w/ everything said in this post!

[ElCheapo]

Dont know really. I use my 93 Corrolla like a slave horse in need of a beating, but it does have a manual trans. Last week I had a 1200 venture and a CB 750 on the same trailer with no probs. However keeping two big bikes separated reminds me of when I was a kid and my dad would reach over the seat trying to get one of us all while yelling you both knock it off.

[mylittleho]

Any vechile can benefit from a trans. cooler. The longer the fluid is out of the transmission, and has a
chance to cool off, the better. I have always put a larger cooler on all of my cars, and have yet to
have even a hint of transmission problems. Another cheap and easy way to get a cooler fluid is to run long lines
to and from the cooler. It increases your fluid capicity - and allows the fluid to cool even more.

If I were going to tow with a Malibu , I would DEF. invest a few bucks on a decent cooler.

Agreed.. and someone mentioning checking the fluid.. and it being OK.. you can't tell anything by the fluid until the transmission starts to slip and then the fluid will smell burnt and by that time the damage is done..

for every 10* over it's operating temp it cuts the life of the fluid in 1/2.. Any vehicle that tows should have a transmission cooler **period** the damage of overheating a transmission can not be seen or felt.. it will just cut down on the life of the transmission and make it fail prematurely.. I run a B&M race transmission cooler on my mustang. The mustang uses a cooler in the radiator which is barely enough for a stock car traveling on a flat surface.. tow anything, or drive it hard, or through the mountains and you have basically overwhelmed the stock cooler which will raise your radiator temp also.. I have bypassed the radiator cooler and run a large 5 speed radiator and a HUGE stand alone transmission cooler designed to cool the transmission for a vehicle's weighing/towing 28,000lbs. I even run a small transmission cooler on my Infiniti G20/Primera since a transmission cooler WILL ONLY EXTEND THE LIFE OF THE TRANSMISSION AND FLUID..

[Gibson]

Ever vechile i've ever seen has gone through the rad stock. i'd still put a cooler on it.
Someone said of haveing 2 transmitions in a Caravan all Dodge front wheel drives are noted for weak/bad transmition's espically Caravan's and Neion's the overdrive one's are the wors't if your not too hard on it a non overdrive in a Caravan is good.