I have a 2002 FX4 with a 4.6L that I use to tow. I've added an aux cooler in front of the radiator and have a gage to monitor the temp. If I hit a head wind or climb much at all the temp still goes over 200. Should I add an electric auxillary cooler? How about a cooler pan?

 

Where exactly is your trans temp sensor? Is it on the trans output line or in the test port, or is it from a scangauge?

What's your trans temps when you are not towing? 200* would not be too out of line if your TC is unlocked and you are on a grade or hitting a head wind..

How much does your trailer weigh? What speed are your trying to maintain during this 'high' trans temp time?

IMO, if you already have the cooler in the grill and you are moving forward, you are getting as much air as you are going to get... An aux fan on the cooler would help in stop and go traffic situations, where there is no real air flow, but I've not found the need for one and I've got the stock aux trans cooler and mechanical rad fan (even at idle, I have a pretty good amount of air flow thru the rad and the trans cooler, so an aux fan is not really needed for me..)

If you are only 'peaking' at 200* temp, then it goes back down to around 180* when you are just cruising, then I would not worry too much about it... I've gotten as high as 210* on a long 6% grade while in locked 2nd gear going an easy 50 mph.. My water temp was 210* as well... Once I got over the top and started on the down side, both temps went down and the trans settled in back to 180* when it was just cruising.. This was when the outside temp was over 90* and I had the AC on in the truck too!

So, give us some more info and we'll see if you really have an issue..

Mitch

 

Thanks, Mitch. The temp sending unit is on the side of the pan. When I'm not towing it varies depending on the outside temp but has been as high as 180 or so when I hit hills or head wind in summer. I'm towing a 26' travel trailer ultralite that is supposed to be around 4600 lbs dry so I know I'm probably about maxed on tow capacity. I've hauled quite a bit with it but I've always just slowed down (60) as the temp goes up. It'll go up to 230 or so before I slow down. I think if I kept pushing it, it would go higher. especially going up a pass in the mountains. I've got the cooler set up to flow through it before the radiator. Should it be after? I've heard both ways.

Bob

 

The aux cooler should be after the radiator cooler. That's a more efficient way to cool the trans.

 

Yeah, that's a good size trailer for sure.. If your truck did not have the factory aux trans cooler installed and you installed one, what kind is it? Is it a 'stacked plate' design like the factory one, or one of those 'tube and fin' ones you can pick up anyplace?

If it's a tube and fin style, then that's your problem there... IMO, they don't cool as well as the stacked plate ones do..

Also, placing it like Mark suggests is the way the factory does it..

My setup is totally stock and I'm getting the trans temps from the trans output line just before it goes into the rad cooler.

If your TC unlocks a lot during towing, then that will drive up the heat considerably too...

Mitch

 

It's a "stacked plate" type I bought online. Not sure what capacity it is. It measures 9" X 12". I'll check tomorrow to see if I hooked it up in series after or before the radiator cooler. Any easy way to know which line is the return? If that's all it takes to make it work better, that would be great! Also thought about a pan cooler but can't find one on line for a 4R70W. A little more cooling and extra capacity may be all I need.

 

9X12 is about the same size as the stock unit!
Put one of these big ones in and you'll be good! I think it's about 15X24
http://www.dieselsite.com/index.asp?...ROD&ProdID=480

Phil

 

I use a combination of a cooler w/ an electric fan, and a double deep pan with cooling fins.

 

I decided to go with an electric fan B&M 130-70297 and deeper pan. It got hot when pulling against a head wind and when 4-wheeling in low range (not much wind to cool) so I'm hoping this will take care of both. The question is now should I hook it in series with the cooler I've got or put it in place of it? Also, where is the best place to put the electric cooler? In front of the radiator? in the engine compartment area? somewhere else? What's the most effective? What about keeping it out of the rain?

 

It's your money.
That little thing with the fan is junk compared to the BIG V10 cooler!Plus it's more expensive,you have to wire it,it's going to get wet(it might be made to get wet)
If it was getting hot going into a head wind ,,,you were getting plenty of air!That little fan is good for traffic.

Phil

 

 

Anything is better then stock!

And here is the how to for installation.
http://www.nloc.net/vbforum/gen-2-li...-intalled.html

Phil

 

Hey, guys, thanks for all the info. I really appreciate it. If I do go with the fan mounted B&M should I hook it in series with the passive 9"X12" one that I already have or would that create too much pressure drop?

 

You could just look into getting an auxiliary electric fan, mounting it onto your existing transmission cooler, and then setting the turn on temp accordingly. Why buy the B&M Racing Hi-Tek if you don't have to?