Tranny Coolers External vs Internal or Both? - Off-Road Forums & Discussion Groups
Go Back   Off-Road Forums & Discussion Groups > Jeep > Jeep-Short Wheelbase

Jeep-Short Wheelbase All discussion of short wheelbase Jeeps: CJ, TJ, YJ and JK



Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 02-08-2001, 12:29 PM
MarkF
Guest
 
Posts: n/a
Default Tranny Coolers External vs Internal or Both?

I just purchased a 4 core Chevy/CJ radiator from Mepco for my 86 CJ7 with a 350 w/ an auto tranny (TF999). The new radiator has an internal tranny cooler. Currently I have an external cooler mounted to my current radiator (using zip ties through holes made in the radiator, I didn't do it I bought it this way).

Should I use the existing external cooler and mount it to the grill? Use the internal cooler? Or some combination of both? If it is both how would I do it? Would the external be first, internal first, what should I use for plumbing, etc?

Thanks
Mark F

1986 CJ7, Chevy 350, D44/D30, more to come shortly
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 02-08-2001, 12:48 PM
Old Hand
 
Join Date: Feb 2000
Location: Minot, ME
Posts: 1,181
Thanks: 0
Thanked 0 Times in 0 Posts
v8jeep is an unknown quantity at this point
Default Re: Tranny Coolers External vs Internal or Both?

I used both. The external cooler went in series with, but after the rad trans cooler (others may disagree saying the fluid may get too cold) . To figure out which direction the trans fluid went, I pulled both lines going into the rad trans cooler and cranked up the engine and noted which one was spewing fluid. For the plumbing, I used steel fuel line to go from the tranny to the front (steel helps to radiate some of the heat, but running rubber hose could be easier?) and to do the rigging into the rad and from the rad to the external cooler, I used the high speed trans line hose that came with my external stacked plate cooler. It's about the size of 3/8 rubber fuel line but it has this high temp fabric tape wrapped around it. Looks like tough stuff, never seen it sold separate though.
I'd also consider running an inline trans temp guage to monitor the temp of the tranny.
big ed

[img]/wwwthreads_images/icons/cool.gif[/img] Big Ed
<font color=red>'88 YJ, 4" susp,3" body,35's,283 Chevy V8,TH350,4.11's,D30,D35c</font color=red>
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote Quick reply to this message
  #3  
Old 02-08-2001, 12:52 PM
Can't Get Enough
 
Join Date: May 2000
Location: Bastrop, Texas
Posts: 1,445
Thanks: 0
Thanked 0 Times in 0 Posts
kerryp is an unknown quantity at this point
Default Re: Tranny Coolers External vs Internal or Both?

How is the one you have now plumbed? I would think you would want to go through the radiator cooler first and then route through the external unit. I would take the intake into the radiator cooler and leave it as is. I would then take a short hard adapter that you can buy at any auto parts store and place it in the outlet on the radiator cooler (this is a hard piece of line that has the screw in connector on one end and a flare on the other). I would then buy some hydrawulic hose (and clamps) of the correct diameter and route it from the radiator cooler adapter to the intake (if there is an actual intake) on the external cooler. Then I would connect the return line of the transmission line on the other port of the external cooler. I would think this would allow you to use both coolers and get the best cooling. I haven't done this in a long time, I have had manuals for the past 12 years so if someone on the BBS sees that I have advised incorrectly please advise.

82 Scrambler, 360, T5, D300, 4" lift, AMC20 (rear disc brakes) and Dana30 with 3:73's and lockers.
Smithville, Texas
Member TX4X4 Cyber Club
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote Quick reply to this message
  #4  
Old 02-08-2001, 01:01 PM
MarkF
Guest
 
Posts: n/a
Default Re: Tranny Coolers External vs Internal or Both?

Right now I only have the external plumbed. The radiator in there is a piece of crap with no internal tranny cooler. My gut inital thought was to do the external first then internal. My logic was that according to the prior owner the current external supposedly has served this vehicle well for the last 12 years (no rockcrawling though). So by using this external first the tranny fluid should be sufficiently cooled or almost sufficiently cooled. Then plumbing it to the internal would not result in it cooling too much because the internal one will be somewhat warm from the engine coolant. This in turn would accomplish 2 things 1) not overburden the main radiator (though w/ a 4 row this shouldn't be problem) and 2) the tranny fluid wouldn't get overcooled.

Mark F

1986 CJ7, Chevy 350, D44/D30, more to come shortly
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote Quick reply to this message
  #5  
Old 02-08-2001, 01:15 PM
**DONOTDELETE**
Guest
 
Posts: n/a
Default Re: Tranny Coolers External vs Internal or Both?

The advantage of external first and then internal is that your transmission will operate at our around ~175 degrees. That is the optimal temperature for a transmission. I currently just use the external on mine but that's because the internal one leaks at the flange. I never really break 110 and only after heavy use has it ever gotten abot 145.

Nick Hagen
1995 Wrangler
3" suspension lift, 3" body lift
33" Mud Tires
TBI Chevy 350 followed by a Turbo 350 tranny.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote Quick reply to this message
  #6  
Old 02-08-2001, 01:44 PM
Keyboard Implanted
 
Join Date: Sep 1999
Location: Southeast Iowa
Posts: 6,394
Thanks: 0
Thanked 0 Times in 0 Posts
CJDave is an unknown quantity at this point
Default Re: Tranny Coolers External vs Internal or Both?

[img]/wwwthreads_images/icons/tongue.gif[/img] Mark, I think you have this clear in your mind based on what you have written. YES....the external cooler goes first. It is for two reasons: FIRST, the difference in temp would be at a maximum, and the most heat would be dissipated before the fluid entered the radiator; SECOND, the fluid would be reheated to working temperature IF NECESSARY by it's trip through the radiator heat exchanger on cold days.[img]/wwwthreads_images/icons/smile.gif[/img] Really serious fluid cooling is usually made by a completely separate unit with it's own fan. It gives the opportunity to cancel the cooling if it is not needed.[img]/wwwthreads_images/icons/smile.gif[/img] Here is something else to remember....if you install cooling coils in the oil sump of a big gearbox like a tranny for example, there is a tendency for the cold plates (or tubes) on the exchanger to condense moisture that is entrapped in the oil. That causes water to collect in the bottom of the sump and it does more harm than than it did when it was moving as a part of the lube oil mixture. FOR THAT REASON, I always avoided in-cavity oil coolers, and took the oil OUT of the gearbox....cooled it some way....and then put it back in. If you notice water cooled oil supplies on big stuff like huge compressors and engines, the coolers are almost always extraneous rater than internal. The rule is: take the OIL TO THE WATER[img]/wwwthreads_images/icons/smile.gif[/img] rather than the WATER TO THE OIL[img]/wwwthreads_images/icons/frown.gif[/img].

CJDave
Quadra-Tracs modified While-U-Wait by the crack moonguy[img]/wwwthreads_images/icons/wink.gif[/img] Quadra-Trac Team.[img]/wwwthreads_images/icons/tongue.gif[/img][img]/wwwthreads_images/icons/smile.gif[/img]
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote Quick reply to this message
  #7  
Old 02-09-2001, 12:48 AM
**DONOTDELETE**
Guest
 
Posts: n/a
Default Re: Tranny Coolers External vs Internal or Both?

Mark -
I have to offer what I know on this. And that is just what I just learned from installing one on my Jeep less than two weeks ago.

It is a 28,000 lb.GVW stacked plate cooler. Same design as the faktorees. This manufacturer says just the opposite of CJDave. But with a reason. He says: in series after the existing in radiator unit. There is in his unit a thermostat that opens when the fluid get to a certain temp (not specified) and then the whole cooler comes into play and does it's thing to the fluid. Until then the fluid apparently just goes by a couple of plates.

JMTCW

sln

Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote Quick reply to this message
  #8  
Old 02-09-2001, 08:00 AM
Old Hand
 
Join Date: Feb 2000
Location: Minot, ME
Posts: 1,181
Thanks: 0
Thanked 0 Times in 0 Posts
v8jeep is an unknown quantity at this point
Default Re: Tranny Coolers External vs Internal or Both?

See Mark, I told you that you'd get mixed views on this!
One more thing, be sure you tighten and retighten all your hose clamps on your tranny cooling system. I had one line blow off, thank goodness someone I knew was behind me and told me! I retighten all my clamps every 4mo or so.
big ed

[img]/wwwthreads_images/icons/cool.gif[/img] Big Ed
<font color=red>'88 YJ, 4" susp,3" body,35's,283 Chevy V8,TH350,4.11's,D30,D35c</font color=red>
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote Quick reply to this message
  #9  
Old 02-09-2001, 09:35 AM
MarkF
Guest
 
Posts: n/a
Default Re: Tranny Coolers External vs Internal or Both?

I hear ya SLN, but I don't know how sophisticated my external or internal tranny cooler is. I'll check the instructions on the new radiator this weekend. maybe that would shed some light as to what I should do for my particular application.

Th eother obvious thing is that it is currently plumbed to the external only so it would be easier to just leave it that way for the time being while I figure this all out.

Thanks again everyone,
Mark F

1986 CJ7, Chevy 350, D44/D30, more to come shortly
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote Quick reply to this message
  #10  
Old 02-09-2001, 09:45 AM
Can't Get Enough
 
Join Date: May 2000
Location: Bastrop, Texas
Posts: 1,445
Thanks: 0
Thanked 0 Times in 0 Posts
kerryp is an unknown quantity at this point
Default Re: Tranny Coolers External vs Internal or Both?

I know I'm about to state the obvious, but... If you are going to leave it as is for the time being, make sure the inlets to the radiator trans cooler are plugged well to prevent them from taking on dirt and crud and plugging it up. [img]/wwwthreads_images/icons/smile.gif[/img]

82 Scrambler, 360, T5, D300, 4" lift, AMC20 (rear disc brakes) and Dana30 with 3:73's and lockers.
Smithville, Texas
Member TX4X4 Cyber Club
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Off-Road Forums & Discussion Groups forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -5. The time now is 06:08 AM.


Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO 3.2.0
Copyright 1994-2009, VerticalScope Inc. // Off Road forums & discussion groups sitemap
side by side | atv | dirtbike | snowmobile | sandsport | competition | land use | Jeep | Toyota | Ford | GM