Lumpskie's 1989 Grand Wagoneer Build

[lumpskie]

It's silver, right? I do remember seeing you. I was just headed home after its weekly "drive it to work". Normally I'm in my Expedition.

It's black, but I think you saw me staring. Your face said "do I know that guy?"


Also, I think I'm going to get a transmission cooler. My buddy gave me a universal bar and plate style cooler he had but I also have the opportunity to buy a used stock setup. Do any of you guys have experience or suggestions?

 

[ExplorerTom]

I've installed several aux transmission coolers. I cooked a transmission one time when the $5 engine thermostat failed and the engine ran near the red while on the interstate in July in Missouri when it was 110 degrees. When I stopped for gas, transmission fluid was boiling out of the dipstick tube. That $5 thermostat cost me $2000 for a new transmission (that I should have never done.....)

Since then, most of my automatics have had large plate style coolers added. I usually get a Hayden or B&M.

 

[thethePete]

^ Yep, and they're easy to install. Especially if you have a factory one to splice off. Cut the line with a line cutter or hacksaw so you have a straight flat edge, and use a brake flare tool to put a little flare into the end, it helps grab the line. Use "fuel injection clamps", they look like little t-bolt clamps, constant tension and allow for much greater clamping force than worm-gear types. Double clamp it if you want additonal security. Other than that it's a pretty straightforward installation. Make sure to top up your trans as you've now added a litre or more of capacity. Check it running and warm. Also make sure you get the correct spec fluid, transmissions are fussy, you can't really fudge around like you can with motor oil.

 

[lumpskie]

^ Yep, and they're easy to install. Especially if you have a factory one to splice off. Cut the line with a line cutter or hacksaw so you have a straight flat edge, and use a brake flare tool to put a little flare into the end, it helps grab the line. Use "fuel injection clamps", they look like little t-bolt clamps, constant tension and allow for much greater clamping force than worm-gear types. Double clamp it if you want additonal security. Other than that it's a pretty straightforward installation. Make sure to top up your trans as you've now added a litre or more of capacity. Check it running and warm. Also make sure you get the correct spec fluid, transmissions are fussy, you can't really fudge around like you can with motor oil.

Well, it turns out I'm an idiot. I already have a trans cooler! It is just so big that it covers almost the entire front of the radiator. So, when I shined my flashlight in the front grill, I though I was looking at radiator rather than the transmission cooler. So, that's one less thing to worry about... even if it was embarrassing.

 

[thethePete]

Does it have a/c? If it does that's your condenser, not a cooler. If not, carry on.

Sent from my SM-G870W using Tapatalk

 

[lumpskie]

Does it have a/c? If it does that's your condenser, not a cooler. If not, carry on.

Sent from my SM-G870W using Tapatalk

It does have AC but the lines pass through the radiator and run back to the transmission. Being a stick shift guy, I didn't know what I was looking at!

 

[thethePete]

Hm. Sounds different than anything I've seen, usually when they go into the rad end-tank, they just have a small heat exchanger in the end-tank that exchanges with the coolant. That's not really an adequate solution, I'd still run an aux cooler.

 

[ExplorerTom]

On "modern" vehicles, the factory tow package usually adds an auxiliary ATF cooler. Did Jeep offer a towing package?

 

[thethePete]

^ Yes, but very rarely do they cover the entire area of the rad core. Usually the rad, a/c condenser and intercooler on a diesel are full sized, the power steering cooler is typically a small heat exchanger, and the trans cooler may be half the size of the rad stack on a big truck with a tow package, usually it's not much bigger than the power steering cooler. That's why I was surprised when he mentioned the exchanger core was the size of the whole rad. (gasser intercoolers are typically half the rad or less, and always quite a bit thicker than anything else in the stack.

 

[lumpskie]

^ Yes, but very rarely do they cover the entire area of the rad core. Usually the rad, a/c condenser and intercooler on a diesel are full sized, the power steering cooler is typically a small heat exchanger, and the trans cooler may be half the size of the rad stack on a big truck with a tow package, usually it's not much bigger than the power steering cooler. That's why I was surprised when he mentioned the exchanger core was the size of the whole rad. (gasser intercoolers are typically half the rad or less, and always quite a bit thicker than anything else in the stack.

^You nailed it! I was expecting something that looked like this:


The one that's in there is easily twice that size. (same height but twice as wide) But I did go through the trouble of following the lines (as they exit the radiator) back to the transmission. And, according to the guys on Full Size Jeep Network, that is how the stock transmission cooler was designed back in the day. I'll see if I can try to snap some pictures for you guys because I've never seen anything like it. (of course... this is my first automatic trans vehicle)

 

[thethePete]

Sweet. I would say Jeep knew they were expecting a lot out of that transmission in a rig that sized going where Jeep people go, and at low speed (bigger core works a lot better crawling than a traditional sized one for a tow package at highway speeds). I'd love to find one, I always liked the look of them and clearly they don't need much to go far.

 

[Bobzdar]

On "modern" vehicles, the factory tow package usually adds an auxiliary ATF cooler. Did Jeep offer a towing package?

Yes, mine has the tow package. It includes deeper gears (3.31 vs. 2.73), an external trans cooler in front of the radiator along with the cooler built into the radiator that they all had, a class III hitch with 5000lbs tow rating and 750lbs tongue rating, and wiring/solenoids for the trailer lights. I had to search a bit for one with the full factory tow package as a few I looked at had either the gears or hitch (or both), but not the external trans cooler.

 

[lumpskie]

Well... you guys were right and I was wrong. I don't have the external trans cooler, just the one in the radiator. The cooler in front looks like it's the AC condenser. So, I think I'll install a trans cooler on my own. Now my question is: How do I do that when there are already lines running from the radiator to the transmission? Don't trans coolers usually use transmission fluid instead of coolant? Where do you tap the transmission for the inlet and outlet?

Thanks for the help, guys.

 

[thethePete]

Already outlined it for you dude.

The lines running up to the rad from the transmission have tranny fluid in them. Your new cooler will have tranny fluid in it too. Ideally, if you can figure out with one is send, and which is return, tap off the send line, simply cut it flush like a brake line and ut a slight flare in either end, run your rubber hose from the ends of those cut lines to your new cooler and secure them out of the way. Make sure you top up your transmission after installing because you'll have added a quart or two to the capacity, plus the bit you lost when cutting the line. B&M, or Transdapt or whoever you get the cooler kit from should have instructions telling you something similar. You could eliminate the stock cooler and just fit your rubber hose over the ends of those lines and replace it with a larger air-to-liquid cooler, but I prefer to keep the stock one in play as well. If you can find a spot where the line runs east-west in the vehicle, near the front, you should be able to make your cut/splice without any crazy bends in your rubber lines. Use fuel injection clamps, and make sure you have about an inch of line, onto the metal line, with about half an inch after the clamp, so it doesn't slip off. It's not under extreme pressure, but there is a moderate amount, and transmission fluid is very slippery.

These kinds of coolers are very easy to install, about an hour or so, and with the reputation of Chrysler group transmissions, this'd be the first thing I would install on any jeep. Good luck, and have fun.

 

[Bobzdar]

The factory setup runs it through both the external cooler and the cooler in the radiator - this helps get the trans fluid up to operating temp more quickly when it's cold out. I believe you move the inlet that currently goes into your radiator to the inlet on the external trans cooler, then run the outlet of the external trans cooler to trans cooler inlet on the radiator. You don't touch the existing outlet line that goes from the radiator to the trans.