Jump to content


Photo

Transmission cooler question


  • Please log in to reply
5 replies to this topic

#1 Mark Cooperstein

Mark Cooperstein
  • Casita Club Member
  • 21 posts
  • Local time: 07:15 AM
  • Location:Big Stone Gap VA
  • Gender:Male

Posted 21 June 2010 - 11:29 AM

Hey all you mechanically inclined gurus of which i am not!!! A maybe stupid question about after market transmission coolers.. I hive a 2002 Dodge Dakota. I will be pulling a 17' LD. My truck has manual transmission. Do I need a cooler? All the talk I have heard about transmissions overheating refer to automatic trannies, do manuals also need this option?

Mark Cooperstein
Big Stone Gap, VA

Ps- T minus 3 days and counting to Casita delivery day!!

#2 Indy-hp

Indy-hp
  • Casita Club Member
  • 333 posts
  • Local time: 06:15 AM
  • Location:Houston, Texas
  • Casita Model/Size:2003 17' SD
  • Gender:Not Telling

Posted 21 June 2010 - 12:55 PM

QUOTE (Mark Cooperstein @ Jun 21 2010, 01:29 PM) <{POST_SNAPBACK}>
Hey all you mechanically inclined gurus of which i am not!!! A maybe stupid question about after market transmission coolers.. I hive a 2002 Dodge Dakota. I will be pulling a 17' LD. My truck has manual transmission. Do I need a cooler? All the talk I have heard about transmissions overheating refer to automatic trannies, do manuals also need this option?

Mark Cooperstein
Big Stone Gap, VA

Ps- T minus 3 days and counting to Casita delivery day!!
A quick search shows the 2002 Dodge Dakota "Towing Group" option requires the "Heavy Duty Service Group" option which includes heavy-duty engine cooling, transmission-oil cooling, power-steering-fluid cooling, heavy-duty battery and alternator, with both automatic and manual transmissions.

For what its worth, I have an optional high-performance package on my sports car daily driver that includes a transmission oil cooler even though I have a manual transmission.
Henry & Debbie
2010 Honda Ridgeline

#3 RadioBob

RadioBob
  • Casita Club Member
  • 76 posts
  • Local time: 06:15 AM
  • Location:River Ridge (near New Orleans), LA
  • Interests:Ham Radio, Shortwave, GMRS, reading, politics, traveling, and of course...CAMPING!
  • Gender:Male
  • Casita Club Directory #:1382

Posted 21 June 2010 - 01:25 PM

Pro'lly not. I just did a quick Google search and the consensus seems to be that a tranny cooler (as in transmission cooler and not an air conditioner for cross dressers blush.gif ) seems to be an automatic thing. I'd research further, though. You can't believe everything you read on the Internet! tongue.gif
Bob Dunn - River Ridge (near New Orleans), LA
Amateur Radio K5IQ
General Mobile Radio Service WPXA535

2004 17' Spirit Deluxe "Gawn Pecawn"
2009 Ford F-150 STX

Casita Club 1382

#4 Fireballsocal

Fireballsocal
  • Casita Club Member
  • 618 posts
  • Local time: 04:15 AM
  • Location:Rancho Cucamonga, Ca.
  • Interests:Glamis, 4 wheeling, traveling, taking stuff apart.
  • Gender:Male

Posted 21 June 2010 - 04:27 PM

Not necessary. While there are transmission oil coolers out there for manual transmissions, they aren't needed for light trucks. Someone is just trying to make a buck. Your stick shift will be just fine as it came from the factory.
1996 17' LD Sold but missed.
1996 Lance 11'4 truck camper. Sold
A new Casita is in my future.

#5 Muttley

Muttley
  • Casita Club Member
  • 879 posts
  • Local time: 04:15 AM
  • Location:Lizard Acres, Arizona
  • Casita Model/Size:2002 17SD
  • Gender:Couple

Posted 21 June 2010 - 07:44 PM

Automatic transmissions generate a lot of heat, more when under towing loads. A lot of it is generated by the torque converter which a stick doesn't have. An automatic has a pump to circulate the fluid and create the pressure to operate the hydraullic functions. The circulation includes to the cooler and back to the transmission. Most sticks don't have a pump and the oil is just splashed around by the turning gears.
2002 SD 17 'Tinker Toy'
2010 Nissan Xterra

#6 thetravelkids

thetravelkids
  • Casita Club Member
  • 276 posts
  • Local time: 06:15 AM
  • Location:Diamondhead, MS
  • Gender:Couple
  • Casita Club Directory #:2583

Posted 22 June 2010 - 04:46 AM

I found this explaination on a Toyota "off-road" website:

Its really not practical to try to cool gear oil with a radiator type oil cooler the way automatics are. Gear oil is very thick and sticky and dosen't flow freely like auto tranny fluid. If you look at your manual tranny, it has fins on the outside to increase surface area and dissipate the excess heat into the air. This is all you need to keep your gear oil at proper operating temp, not too hot, not too cool. The oil has to be hot to work effectivly.

Most of the heat in auto tranny fluid comes from the tourque converter which a manual does not have. Towing increases this heat dramaticly but still, it comes from the tourque converter which is really just like a fan 'blowing' fluid onto a windmill that drives the gears and driveshaft. The tremendous friction in this process is what cooks auto tranny fluid. Unless you always drive with the clutch half engagued this friction and heat does not occur in a manual transmition.

In order to fit a radiator type cooler to a manual tranny you would have to come up with some sort of pump that is strong enough to push the thick sticky oil through a bunch of skinny hoses to a cooler where it will get even thicker and stickier before it returns to the tranny. Such a pump would rob a lot of power from your driveline. Also you would have to drill and tap holes in your tranny or drain and fill plugs to fit the hoses. There are too many ways for such a system to leak or fail and it will over-cool and thicken the oil reducing efficentcy.

FYI NASCAR teams use manual tranny and differential coolers and pulley driven pumps but run free flowing oil in them that is more like motor oil than normal 75w-90 or similar gear oil. Also they change trannys and diffs and the oils every week. It won't work.
Bob & Pat
2012 Evergreen Element ET26SLR - "Ms Ellie"
2007 Casita 17' SD, gone but not forgotten
2012 Ford Expedition Limited
Visit us at www.katrinacasita.wordpress.com
Posted Image