Author Topic: Transmission cooler?  (Read 883 times)

0 Members and 1 Guest are viewing this topic.

Offline jfrabat

  • Gargantuan Mango Tree MechanicŪ
  • Member
  • *
  • Posts: 3676
  • Finally USING the Jeep!
Transmission cooler?
« on: May 19, 2016, 02:20:27 PM »
I know most of you have the issue that on long trips, the transmission tunnel gets rather hot.  Usually it is an inconvenience, but in my case, when it it already 100* outside, and you are driving 13 hours from San Jose to Panama or back, it gets to be a bit more of an issue (especially since the AC cannot keep up!

Now, first, I would like to know if anyone has taken the time to figure out if this is the transmission or the Transfer Case that is getting hot.  I know in most cases the TC does not turn on road, but it does on mine (solid front axle).  But, my bet is that it is the transmission that's heating up.

If it is, is there any way to put a cooler on it so that it will not get as hot?  Would that be a bad idea?  Among my worries in doing so would include snagging a cooling line while off-roading...  But what do you guys think?  Have any of you done anything about this?
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline dwtaylorpdx

  • Member
  • Posts: 1038
Re: Transmission cooler?
« Reply #1 on: June 10, 2016, 08:43:37 PM »
Hmm. Is it an Auto or manual trans,,, ??

No such thing as too much cooling on an auto..

You can put a electric pump on the trans and a external cooler. Will cost 400.. to 600.... 
THis is just one option off a "transmission cooler" search on Jegs.
http://www.jegs.com/i/Derale/259/20561/10002/-1

This goes on an Auto, to use it on a manual trans you add a couple fittings to the trans and pump the fluid through the cooler with an external electric pump. On the manual trans Youll want a hole for a thermo switch that turns on at about 175.

http://tiltonracing.com/product/cooler-pumps/

Lot of variations, the tube style cheap heat exchanges don't work near as well as the plate style, you can also buy many of these components if you are good with waiting for a couple weeks extra off AliExpress.  But this gives you an idea.. You also should consider Aeroquipe style braided hose on this application... Or at  least Goodrich Push fit.   


If its still an AX5 or AX15 I'd wonder whats up with the overheating. Mine has > 225K miles and never overheated that I've noticed.
94 YJ - 2.5 Hesco Cam B&B Ported - AX5 Trans w/Centerforce Dual Friction Clutch - 4" Rough Country Lift W/Skyjacker Shocks - D44 Rear/ARB - D30/ARB - ARB Compressor - Warn M8000 in Custom Bumper - Reunell Rear Bumper - Metalcloak 6" Body Armor Kit - Tuffy Console - 265x85-16 Tires - 2M Radio

Offline sharpxmen

  • Chief Squirrel BlowerŪ
  • Member
  • *
  • Posts: 7093
Re: Transmission cooler?
« Reply #2 on: June 16, 2016, 12:11:04 AM »
it is the transmission getting hot. the challenge with a manual and a cooler is that when you add the pump you need to figure out a way to maintain the level, or you do dry sump but then you need rails or nozzles to spray fluid on the gears. easiest way is to add insulation under the tub (above the transmission but glued to the tunnel and not just resting on the transmission or it won't have enough cooling) and in the cabin on the tunnel - there are some aluminum coated blankets used in hvac that would probably work.
Even if you add a cooler it will still get hot enough to radiate inside.
'95 YJ, NSG370 6spd / Hurst shifter, Dana 300 + 4:1 Doubler / tri-stick, Custom skid, Super D35 / Auburn LSD / 4.88, 35x12.5x15 BFG KM2, 64mm t/b, 1.7 RollerRockers, MkVIII e-fan, Dual Diaph Booster
Latest: Corbeau BajaRS heated seats :dance: keeping warm the rear end

Offline jfrabat

  • Gargantuan Mango Tree MechanicŪ
  • Member
  • *
  • Posts: 3676
  • Finally USING the Jeep!
Re: Transmission cooler?
« Reply #3 on: June 16, 2016, 08:04:47 AM »
it is the transmission getting hot. the challenge with a manual and a cooler is that when you add the pump you need to figure out a way to maintain the level, or you do dry sump but then you need rails or nozzles to spray fluid on the gears. easiest way is to add insulation under the tub (above the transmission but glued to the tunnel and not just resting on the transmission or it won't have enough cooling) and in the cabin on the tunnel - there are some aluminum coated blankets used in hvac that would probably work.
Even if you add a cooler it will still get hot enough to radiate inside.

I thought about using some sort of insulation, but my worry is that once the mud gets stick between the insulation and the sheet metal, rust will creep up...  But what do you think?
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline Eucalypta

  • Member
  • Posts: 147
    • Eucalypta Oud-Hollands Snoepgoed
Re: Transmission cooler?
« Reply #4 on: June 21, 2016, 01:31:11 AM »
What about a heat-shiel like used on the back end of the muffler: Just a sheet of metal between the transmission and the body; bolted about an inch off the tunnel?

I guess you already removed the carpet from the interior; this had also some insullation under neath; maybe replace it or add more insulation underneath?


To Boldly go where no one has gone before - James T Kirk
1994 YJ 2.5L - 1996 ZJ 5.2 V8

Offline Jeffy

  • Administrator
  • Member
  • Posts: 14934
Re: Transmission cooler?
« Reply #5 on: June 21, 2016, 01:43:34 PM »
You can add heat shielding to the floor from the inside.  Stuff like Dynamat have some types that have heat shielding on them.  You can also get carpet insulation with heats hielding.

Stock carpet had no insulation of any type under it.  It was a sheet of carpet with velcro under it.

The underside of the jeep is coated with undercoating so rust shouldn't be too much of an issue.  That does make it a problem with sticking adhesive backed insulation/shielding under the body though.
Youtube Channel: https://www.youtube.com/channel/UCZNlr60GXH5OlKIFrT7P6mg
My Jeep: http://4bangerjp.com/forums/index.php?topic=2783.0
"If the motor car were invented today, there is absolutely no way that any government in the world would let normal members of the public drive one."

Offline jfrabat

  • Gargantuan Mango Tree MechanicŪ
  • Member
  • *
  • Posts: 3676
  • Finally USING the Jeep!
Re: Transmission cooler?
« Reply #6 on: June 21, 2016, 02:15:53 PM »
For everyday use, I do have a carpet, but because of the console, the tunnel is not covered (since I remove the carpet for offroading, there is no carpet under the console, and I have a rather big console).  But I do like the idea of a metallic heat shield...  I will look into it and see if I can figure something out.  Maybe I can even use a think aluminum sheet to make it (light weight and rust free!).
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline VA_YJ

  • Member
  • Posts: 282
  • Now I need a CJ...
Re: Transmission cooler?
« Reply #7 on: June 30, 2016, 09:43:56 AM »
I have not tried it, but there is ceramic spray-on heat insulation (e.g., Lizard Skin) that you can apply and it does not allow water to creep in.  The race car folks spray this stuff onto the floor board to cut down on heat in the people compartment.
95 YJ, 31 BFG ATs, 4.0 TB & spacer, Banks header, DynoMax CAT back, 19# inj, AEM CAI, 20 gal mod, Optima yellow
98 TJ, 35 BFG Krawlers, 4.0 liter, ax15, atlas 5:1, armor, Super 88 (under construction)
96 XJ Cheep Cherokee, 33s, 4.0 liter, AW4, future project
89 Waggy, 360 V8 727 dana 44s, it runs