Transmission cooler and the bypass...Question

[Killswitch]

This is something that I'm working on, posted it on another forum but figured I'd bring it over here and see if anyone had any knowledge to share on it.


I'm looking at doing the bypass before I run out of my 80k mile coverage. Right now I'm at 70k.

My plan is to install a temp gauge for the last 10k miles and monitor temps on the stock set up. Once I hit 80k I'll do the bypass and install some more cooling capabilities and continue to monitor temps.
Here is what I initially plan on using to monitor temps:
http://www.summitracing.com/parts/BMM-80212/

Once I get out of the 80k mile warranty I will be doing the bypass no matter what. I'm thinking about removing the stock tranny cooler completely and replacing it with this:
http://bmracing.com/?wpsc-product=h...ng-system-13-12x9x3-12-with-9-12-diameter-fan

My first question is has anyone tried this? Is there any reason that this wont work?
Secondly, what are the opinions on this set up? To me it seems like this would be more effective than just stacking two coolers together? This cooler has far more capacity than our stock ones. I may have to cut the grill a little bit to make it fit but if that's the only issue I dont care.

I know this has a high price tag. You could make something like this using similar parts:
B&M has a cooler for about 80 bucks that is similar to this without the fan although it is only half as thick
ProComp has a 9" fan for like 15 bucks on amazon
Derale makes an inline thermostat for about 30 bucks
So all this is easy to recreate.
I'm looking for opinions suggestions on this set up, any advice would be helpful.

 

[Killswitch]

So, the main question is that once the bypass is done and that ATF is no longer passing through the radiator, do people think that that B&M cooler with the fan will provide enough cooling power by itself to keep the ATF within operating specs?

 

[Xtacular]

Why not do the bypass before you hit 80k? Personally- just my opinion- but it seems you are flirting with disaster. If it fails within the extended warranty, best case you will be without your X for a while and won't be able to do the work on your own timeline. I HATE waiting for my X to be done, even if it's just an alignment lol. Versus just bypassing the cooler on a weekend and not having to worry about a thing, and saving your valuable time.

 

[granitex]

There is no reason to wait to do the work, if anything I would do it as soon as posable, and add an inline filter. Cheap insurance for the life of the tranny.

 

[Killswitch]

Alright, just to update this, I had actually already posted in the other forum that I am going to do the bypass sooner rather than later.

More importantly I wanted to know if anyone had run this cooler to see if it was getting good numbers as far as cooling the transmission by itself with out the help of the radiator. In my searches I was able to find a pathfinder guy on clubfrontier that has run it and he went from running about 204* to running 174* (that's ATF temps) so this thing definitely works.

So, this week I'll get paid, I'm going to order the following:
Hi-Tek Transmission cooler that I linked up above
B&M trans temp gauge that I linked up above
And then may do some other stuffs as well, thinking about putting a different thermostat in and probably going to flush the radiator etc.

Hopefully that will all come in in the next couple weeks and some weekend here I'll be able to do the bypass as well as install that new cooler and I'll post up results.

 

[Macland]

Post up a how to!

 

[Killswitch]

will do, still trying to get all the parts that will make this simple. For example I'd like to avoid cutting the aluminum trans line. I'd rather put the temp sending unit in the rubber hose. So I'm basically buying a bunch of parts, I'll use what I need and then once I have it all figured out I'll put up a how-to.

 

[dhyde79]

ok, well, I can tell you this, I have a bullydog and I always have it monitoring transmission temp and coolant temp, my trans temp never gets above 170F but my coolant ALWAYS runs 195-215F so, by bypassing the radiator portion of the transmission's cooling setup, I'm actually keeping the transmission COOLER than if my ATF were running through the radiator still, as it would be getting heated by the higher temp of the engine coolant.

 

[Killswitch]

Hmmm, that is interesting. I have seen alot of people after doing the bypass saying their temps were up in the 190s and near 200 or higher, especially when under heavy use (towing or wheeling). My concern is not so much driving around town as it is spending 6-8 hours in 4l0 going 5mph. Then I feel like the transmission could get extremely hot. There is a guy on TNX who goes by jeff_redx who has done some pretty extensive studies on all this. I still need to go back through all his data but I feel like having this extra cooling power after the bypass would be a good thing.

So you are saying thought that with the bypass you are usually running around 170 in the trans? Is that on highway or stop and go or what? Just curious because that is probably the lowest I have heard anyone get post bypass.

 

[Killswitch]

Here's some good info about it all: There is a second thread for the following year as well. I still need to go through all of this myself. I went through it all sometime last year but have not retained nearly all that info lol.

 

[dhyde79]

Hmmm, that is interesting. I have seen alot of people after doing the bypass saying their temps were up in the 190s and near 200 or higher, especially when under heavy use (towing or wheeling). My concern is not so much driving around town as it is spending 6-8 hours in 4l0 going 5mph. Then I feel like the transmission could get extremely hot. There is a guy on TNX who goes by jeff_redx who has done some pretty extensive studies on all this. I still need to go back through all his data but I feel like having this extra cooling power after the bypass would be a good thing.

So you are saying thought that with the bypass you are usually running around 170 in the trans? Is that on highway or stop and go or what? Just curious because that is probably the lowest I have heard anyone get post bypass.

stop & go (and when I go, I go hard), LONG highway driving (800 miles each way, only stopped for fuel), and doing some crawling and trail running, only once have I seen it spike up around 190 and that one time was after I'd been doing a lot of stop & go around town, and was hauling about 500lbs of extra crap around with me.

with temps in Amarillo getting up into the 100's now, I'll make a point of keeping an eye on it, but, I've never had any temp alarms go off on the BD unit either...so, I suppose regardless of temp, they're within safe margins....my point still stands though, if you're running through the radiator, it's going to be RAISING your temps now lowering them, my coolant temp is **ALWAYS** higher than my transmission temp...

 

[Killswitch]

Cool, ya I'd like to hear what results you are seeing. I'm going to proceed with this project regardless as I dont think it's going to make the ATF TOO cool or anything. There was talk around clubfrontier about there being a bypass within the OEM set up where if it is cool enough then it will stop running ATF through the cooler (so people up north may want to look into that) For me in Virginia though, I just dont see the tranny getting to cold as being an issue.

 

[Killswitch]

Alright, I found all the parts I'll need to make this install work. Obviously the bypass will still be the bypass.

I'm going to flush the lines that used to run ATF through the radiator and then cap them up and no longer think about them.

From there, the hard lines that come out/in to the transmission are 5/16" so I'm going to be installing an adapter that has a 5/16" compression fitting on one end and converts to a 3/8" barb. I'll pull the OEM 5/16" hoses that run up to the tranny cooler as well as yank the OEM tranny cooler out of there.

I'm going to use some small "L" brackets to mount the Hi-Tek cooler in place. I found some 90* adapters that will bring the 1/2" NPT connectors on the cooler down to 3/8" barbs. From there I'll just plumb new 3/8" hose from the above mentioned 5/16" adapters up to the cooler. It should take between 6-10 feet, not positive how much yet though.

Lastly I'll wire up that fan with a 15A inline fuse and it'll be good to go.

The only other thing I'm going to do, since I want to be able to monitor my temperature is install a temp gauge. B&M makes a nice one with a 5/16" "T" that has compression fittings on each end. I'll splice that into the OEM transmission hard lines and plumb the wiring for that and it should be all set.

All parts should be ordered this weekend. Hopefully within a couple weeks I'll have it installed and I can put up a full How-To: with a bunch of pictures and fun stuff like that.

 

[Killswitch]

This is a really basic diagram but this is roughly what will be happening:
hopefully this is big enough for you guys to read

 

[mudchet]

Hey Killswitch any update on this? I need to do this bypass and would like to hear how yours is going.

Thanks.

 

[dhyde79]

mine's been done for over a year now, and driving in 100+ degree texas heat hasn't bothered it at all.

 

[mudchet]

What size trans cooler did you get? I went Autozone and they had three different sizes.

 

[dhyde79]

I left the stock one on there and didn't add anything. I've not had any trouble with anything heating up. To top it off, I've got a Hella 500 lamp sitting directly infront of it (behind the grille)

as it's been said hundreds of times on lots of different forums. The part going through the radiator isn't for COOLING the transmission, it's for WARMING it faster. the radiator temp is often far hotter than the transmission temp. By bypassing the radiator, you aren't taking away any cooling, you're eliminating some of the capability to keep it warmer in the winter (so, if you're in Canadia or Alaska you might care, otherwise, it shouldn't bother you at all.)