And would this do any good? We overheated (the engine) going up a looong grade (I have another post going on this) and I'm thinking that the hot trans fluid helped to heat up the engine coolant. What is the best way to prevent this? Can I bypass the heat exchanger under the turbo? Should an auxiluary cooler be added instead? Should I add a temp controlled fan to the front of the existing cooler?

All was well when the TC was locked up. TC unlocked and/or shifted into 2nd when climbing the steep grade and slowly the engine temps went up.

What do you all think?

Thanks, Mike.

 

Either way you are heating the engine coolant with the transmission fluid. If you eliminate the heat exchanger and put an auxilary cooler in, it will have to go in front of the radiator. How hot is hot? By todays standards 235 degrees is hot, that is the temperature that most cooling fans come on at. If it is getting to hot climbing you need to find the cause. If the transmission is making the engine hot then something is slipping to make the heat. I doubt the converter unlocking is the cause of the heat. Fan clutch not working would sound better.

 

An unlocked converter creates an incredible amount of heat and is very likely the cause of your problem. You will burn up your tranny doing very much of that if the heat becomes too high for too long. The best way to prevent it (IMHO) is to install a torque converter lockup switch so you can keep it locked when pulling in second gear. I would also suggest a trans temp gauge and you will be able to see how quickly and dramatically your temps go up. BTW, the heat exchanger is part of your trans cooling system so removing it would be kinda like shooting yourself in the foot, again MHO.

 

Is there any valves in the heat exchange? Can trans fluid and coolant only go 1 direction through the heat exchange? Or can it flow both ways?
Season I ask is cause I blew my trans and while flushing out the Trans lines can only get air to go 1 direction through everything.
Any help would be great. Thanks.

 

could someone take a picture of this part? I bough my 99 back in Maarch and they said it needed a tranny cooler... they also had it listed as a V8... so I don't think they know their butt from their thumb... anyways... I figured out the is something missing under the turbo and this sounds like it...

Could anyone post a picture or describe what it does?...

 

I hope its ok to bypass..I did mine about 2years ago..
while I don't tow heavy loads up steep hills, I do a 4k trailer daily..
so far no problems..other than keeping the electric trailer brakes working, but this isn't related to the heat exchanger. My truck has an additional tranny cooler on the driver's side of the condenser (AC) coil. I have an additional cooler I'd like to mount, but haven't figured out the where yet.

next on my list is the tranny temp sensor..and several other temp sensors

iwhitene, the exchanger in located under the exhaust manifold, I sure you can find the turbo..look underneath this.. I see it serves 2 functions help to limit the tranny temp to coolant temps..also help to raise the tranny temps using engine coolant..

-dkenny

 

I know where it mounts... It looks like mine has been bypassed... looks like the po removed it... but he also installed an aux tranny cooler.. although it looks like he spliced into the stock tranny cooler instead of replacing it... so I guess I have two tranny coolers running inline...

should I be worried about not have the heat exchanger?

 

Only if you really hammer on the truck and/or tow a lot.

 

well I def. do not hammer on it or do much towing for that matter (i get enough of that at work in my furd) anyways... I got this truck for fuel mileage and plan on driving it a long time. running 50% wmo and getting 19.5 city! a tow a hay wagon now and then though