Good god man! I knew you were full of knowledge, but da?mmit you are good
rep's to ya!!

 

I tried but I need to spread some.

 

Damnit Mark, do I always have to fix your mistakes?

 

Liv - check your "User cp" info ..........

(for humor value)

 

Hahahaha

Thanks bud that makes me feel special.

 

Here is an informative link on the TorqShift - supplied to me by Brickie.

Find a post of his and give him some rep points for me!

Ford 5R110W Torqshift

 

Mark hope you don't mind this added.This is one of your better works, great info my friend !Ford 5R110W TorqshiftSorry I didn't see you caught it all ready. Great to have you here sharing all the goods.

 

Cut away of Torqshift.This is a pretty cool view of the tranny. Ford Genuine Parts Torqshift 5 Speed Automatic Transmission - Cutaway Creations

 

Good idea for a single tranny data locale and great info to start it out. Green square to follow.

My previous vehicle was a 2004 4Runner V-8 that I installed a trans temp gauge on. The sensor was located on the "hot" side of the external heat exchanger. Most of the time, the trans fluid is at ambient air temp. A very good trans mechanic once told me that the fluid is routed through the radiator not for cooling but preheating.

I mention this in contrast to what we see on the dash trans temp gauge which gives the impression of much warmer (and sometimes much cooler) temps than one would imagine.

Bob

 

Your very good trans mechanic is wrong. The fluid is routed through the radiator transmission cooler is there ONLY to cool the fluid. It never preheats the fluid.

I've measured temperatures in and out of the trans cooler and in and out of the radiator at ambient temperatures from -40F to +115F. The ATF is NEVER heated by the in tank cooler.

 

We're talking about the same radiator/heat exchanger, right? I'm talking about, on my previous vehicle, transmission fluid is routed through the engine coolant radiator before it goes through its own transmission heat exchanger (cooler). It's this coolant radiator (usually referred to as "the radiator") that I refer to. This radiator starts heating up as soon as you start the engine and will, over time, warm up to normal op temps at idle. Trans fluid is circulating through this radiator the whole time with no trans work being done. This is the preheating I refer to.

I don't consider myself dumb or inexperienced but I can't think of a single subject that I feel comfortable using words like "never" or "always" about, particularly when there is a very real possibility I didn't understand the comment.

Your rep is exemplary!

Bob

 

Mulepick, read Mark's sig

 

I appreciate his reputation and the knowledge/experience suggested in his sig. None of this is lost on me when I was astounded by his reply. What has me stumped is resolving his significant expertise with basic laws of thermo dynamics. Both are compelling to say the least.

I believe there is a misunderstanding on what fluids/exchangers I'm talking about. At its simplest, however, I'm pretty sure that as I run a pipe of 72 degree fluid through a bucket of 150 degree fluid I'm going to see a boost in temp. Now, things may have changed since I went to engineering school, and I know a civil engineer is not an automatic transmission engineer, but I'm still going to side with Ike Newton, Carnot, and Gibbs on this.

Bob

 

One thing about Mark's statement makes me agree with him. The engine has a t-stat that restricts flow thru the readiator till a pre-set temp. is reached. Most tranny fluid flows immediately thru the rad. Since the tranny is instantly, almost, heating its fluid thru friction driving the vehicle, I think its fluid under most circumstances would need cooling before the radiator is even up to the t-stat temp.

 

The part that you're forgetting is that the engine radiator is there to cool the engine's coolant. By the time that coolant has made it from the end of the radiator where it entered at engine temperature to the side where it leaves to go back to the engine it has cooled considerably. That's what a radiator does. I've measured as much as 100F drop in coolant temperature from the hot to the cold sides of the radiator. This is on a fully warmed up engine. It's an even larger drop on a cold engine when the thermostat is closed.

The ATF is run through the cold side of the radiator. Now if the engine is running at 200F and the coolant loses 100F going through the radiator the ATF cooler is surrounded by 100F water, not 200F water. That's the part that most people seem to have a hard time with. The radiator is NOT at engine temperature.

Always and never are pretty strong words. There is a possibility that there is some condition that I didn't test that does something weird. I did test in ambients from -40F to +115F, and at no time was it even close. The ATF was ALWAYS warmer than the coolant in the cold side of the radiator.