I got a question for you desert rat/rock crawling dudes

I'm looking at putting a tranny cooler on my 98 XJ. Basically, I've got this BM Super Cooler sitting around, and figured, well, why not put a tranny cooler in?

I'm still nervous about automatic transmissions, having had a lot of them go in the past.

Anyway, I've got the cooler, the ability to mount it, an if I dig around, I'm sure I can come up with some 3/8 PS or Transmission hose- so its like a no-buck modification for me.

I've searched.... and searched... and then searched some more. Seems everyone has a different opinion (and we all know what they are like) about where / when to mount the cooler.

That's all well and good. But I want to know from you guys who live in So Cal, drive in the shitty traffic, wheel the trails I'll be wheeling and so on.

I want opinions that might be relevant to me.

The old arguement for

Trans--->radiator---->aux. cooler---->trans

vs

Trans--->aux. cooler--->radiator--->trans

vs

Trans--->aux. cooler--->trans.... and to heck with the heat exchanger.

I'm torn between the first two options. On the one hand, the XJ sees 2000-3000 miles a month of daily driving, sitting in traffic commuting, and I'd kinda like the auxilary cooler to drop the fluid temp right before it goes back to the transmission. On the other hand, I do drive on trips to the north, and I worry that in the winter it could lead to fluid that is possibly too viscous, and maybe I should run it to the cooler first and then the heat exchanger.

To me it makes more sense to run it trans, radiator, aux cooler, trans... in theory the hottest it is coming out of the trans, then going through the radiator, then the aux cooler then back. The other way, it comes out, gets cooled, gets heated, then goes back.

Sheesh.

Anyway, any of you guys down here put one of these in? Which way did you route the lines... and the part that sucks: why did you route em that way.

(hoping this doesn't get moved to tech... cause I don't care what the world outside So Cal or the South West has to say at this point)

Thanks.

i would put it in after the radiator, otherwise like you said, it would cool and just get heated up again. i wouldnt worry about the fluid being too cold going back in.

Run it so it deops the temp before hitting the trans....nevermind your trips to the north, these engines run hot enough, i highly doubt it will get to viscous...

I actually just swapped in the radiator (3 core brass) high flow water pump, and 180 degree robershaw t-stat, and now, unless I'm on the highway, the Jeep doesn't really heat up... lol. I might put a 195 back in.... wanna play for a week or two.

Thanks guys. That's two for hottest, hotter, hot, back to trans.

trans, rad., cooler, trans... That's how mines setup.

they all get about 210. even the race truck................................................:flamemad:

Matt, where is "Down on the Farm" ???

(just wondering vis-a-vis traffic and temps.)

Thanks

rick_1710 said:

they all get about 210. even the race truck................................................:flamemad:

Click to expand...

transmissions?

With coolers or without?

Isn't that too hot for longevity of the unit? I'd thought 150, give or take 25 or so was where it wanted to be.

I run 2 coolers in line so I have trans-cooler-cooler-trans and my trans temp has never hit 200+ (coming out the trans)and warms up to about 140 even in 30 degree winters and snow trips (believe it or not the engine will heat up the trans some no matter what you do). with one cooler feeding the other I have the adjust ability to re-route the line and back feed the trans if necessary and I can still keep a cooler in line if I spring a leak

rick_1710 said:

they all get about 210. even the race truck................................................:flamemad:

Click to expand...

yeah but with the gearing you have you beat the shit out of your tranny, I really doubt he will run 6:0 gears in his axel

over2land said:

Matt, where is "Down on the Farm" ???

(just wondering vis-a-vis traffic and temps.)

Thanks

Click to expand...

Near Fresno. I've got both of my rigs setup this way. The CAT spends most of it's running time out in JV. I've never had a tranny problem with either rig.

Matt

Gerr- neat idea with the redundant systems... but I am seeing myself putting an oil and or PS cooler on this thing too.

Matt- gotcha, thanks.

Anyone use the B&M supercooler for this? I used it in the 715 for PS fluid in front of the radiator and had overheating issues... I was just wondering if it didn't flow enough air.

he he I have those on too

All in the grill?

I have always plumbed the cooler just before the transmission.
Also a good quality cooler like a Earl's, or Seatrab, of comparable size is three times more efficient in terms of heat rejection as a typical tube and fin type cooler.

over2land said:

All in the grill?

Click to expand...

all in the grill stacked as follows

radiator (modine large bore)
ac condensor (modine plate version from f-150 smaller thinner and more efficient)
ps cooler (factory ac condensor in factory location)
both trans coolers (side by side first one is a f-250 v-10 trans cooler second is f-150 4.6L cooler both from napa and fit perfect no rubbing or clearance issues)

I had access to many many many parts for test fitting from my old work's wreaked and abused trucks that is why my stuff is usually a ford part ive made work. My new job is the same way but with chevy and toyota parts

pottenger said:

I have always plumbed the cooler just before the transmission.
Also a good quality cooler like a Earl's, or Seatrab, of comparable size is three times more efficient in terms of heat rejection as a typical tube and fin type cooler.

Click to expand...

I have the smaller one that can be seen here.

http://www.bmracing.com/index.php?id=products&sid=4&cat=20&subcat=&pid=75

Likely I'll take the fan off it and use it.

Its stacked plate.

Gerr said:

all in the grill stacked as follows

radiator (modine large bore)
ac condensor (modine plate version from f-150 smaller thinner and more efficient)
ps cooler (factory ac condensor in factory location)
both trans coolers (side by side first one is a f-250 v-10 trans cooler second is f-150 4.6L cooler both from napa and fit perfect no rubbing or clearance issues)

I had access to many many many parts for test fitting from my old work's wreaked and abused trucks that is why my stuff is usually a ford part ive made work. My new job is the same way but with chevy and toyota parts

Click to expand...

Got pics? (should I search?)

I know I posted pics when I did it, have since gone through a comp change so I dont have any good ones of the build. I can take a couple from throught the grill when it stops raining/snowing. the hardest part was making the new ac condensor fit and moving the radiator back 1/2 a inch

Ditch the rad cooler. cap it off and be done with it.
I run the biggest tranny cooler on my jeep with a dedicated fan. Oh and its mounted out back so as not to block cooling to the radiator. my power steering cooler is mounted under the radiator with its own fans. They all work good. of course It doesn't see snow duty. but I used to take it up to the snow when it still had doors and stuff. yes I still ran just the cooler and it worked great. no problems.