So, you guys with a trans temp gauge...how hot is too hot?? When is it time to pull over and let things cool down?? I've got a temp gauge and never had an overheat issue, but I'm getting a trailer so I'll be doing some towing now and don't have a good feel for how the trans will react??

I know trans fluid is basically hydraulic fluid, and thus completely different aspect from engine oil for example. Is is kind of ideal to keep trans fluid as cool as you can physically keep it, do you want 'some' temp, things like that. Thanks for any tips guys!

Oh, any predictions on how the old 4R70W will hold up doing some healthy towing....65,000 miles, Factory Tech vavle body, and always Amsoil ATF fluid???

 

I believe 230 degrees is the stop number, but that depends on where the temperature is picked up from

 

Good point...I have my temp sensor installed in the line running from the trans to the cooler. Theoretically, this should be the hottest measurable fluid in the system....or so I've always been taught.

 

is it the line on the P/S? of the cooler, i believe this is the return line to the tranny, it first goes to the radiator, then from the radiator it goes to the tranny cooler then back to the tranny, so i believe you are reading the fluid after it has been cooled.

 

Ooops...thanks bigtruck, you are absolutely correct and I mis-spoke. I have it tapped into the line going to the radiator. I am positive I have it in the correct line and not the return line from the 'cooler'!! Thanks for checking though.

 

no problem

 

I have been thru this, so here is what has been the case for me.
After awhile balloned the converter pulling up to 12,000 gross weight up a steep hill to my home . The worst part of the whole trips each time.
Had the trans custom rebuilt; instead of a stock rebuild rather than have the same thing all over again.
As far as temp goes, the output from the trans is the hottest point. Depending on what your loading is at any peticular time on the road. I see temps as high as 250° in the output of the converter.
Synthic fluid will take upwards of 260 before degradation begins to be a factor. You can't get away from hi temps out of the converter. This is where fluid shear takes place when not in lock -up.

My line still runs thru the radiator then to a large cooler with a fan. The fan is set to come on at about 185° as sensed at the radiator input point.
The trans has a deep pan, mid level Raybesto linings, hi volume pump, diesel converter, valve body mods for good shifting as well as other heavy duty changes in the trans and now uses Dextron fluid.
So far this has been the answer to heavey towing.
I would reccomend you have at least 3.73 rear gears or lower and change the fluid often plus a large cooler.
So far so good and love the shifting.
All this with a 4.6L
Trans job was done custom by Level 10.
Bottom line is expect and hope not, that you might have trans failure sometime depending on loads and how often you tow and terain you cover.
Factory didn't put the best parts in that could have been used for towing near the limits of the truck.

 

Thanks for that...So, what should one expect for a good trans re=-build if required (I know depending on parts required) and a new converter??

 

I can't address what you would get from any other builder.
I got the whole load and the cost was substantial from Level 10 whom I had known about for many years and builds competition and custom transmissions for all kinds of cars and trucks.
When the time came to do it, I went right to them with the situation instead of rebuilding stock, which any rebuilder does, but wanted the reputation behind the job. I could not take any more chance of failure than possible.
I got personal service from the owner and was shown their building lab and test equipment. It's nearly like a hospital OR room.
They done things that i'm not fully awhere of.
Special pressure control valve, larger torrington bearings, special drum, hi-flow fluid pump plus the double disc diesel converter.
They back flushed the radiator, the cooler and lines with heated cleaner to be sure there was no trash, checked flow rate, changes out the tranfer case fluids, did the whole job and test drove the truck.
That was a year ago with not even a hint of any problems to date.
That kind of service you pay for and I can tell you that it is more than the cost of most rebuilds you hear about, even the good ones.

 

My trans 'towing' temps are right around 180* when the TC is locked. Going up the grades and stop and go traffic, I'll see 210*.

I just serviced my trans with 171,000 miles on it and it was very clean.. Filter was very clean as well, but it got changed anyway...

My trans sensor is in the line that goes to the rad. I've towed in 90*+ outside temps with the AC going in the cab and have not seen more then 210*

My trailer weighs #5000 soaking wet, so I'm not towing all that much, but I find my trans temps go to 180* when I'm not towing at all.....

I dunno... If my trans temp ever got to 220*, that's when I would start thinking about what I should do....

MItch

 

Is this a 4r70w,e40d or 4R100? The 4r70w they couldn't have done a "double disc" diesel converter in. The e4od they could use a 4r100 converter which are actually triple plate. The 4r100 all the converters are the same. There were a few years of double disc converters but they failed terribly. Ford went through the design a few times and finally got it done right in 01/02. The earliest powerstroke converters were major trouble. They had pieces welded inside them to hold the lockup plates. The welds would breaks and you would have parts floating around knocking every last fin out of the inside of the converters. You just pour them out.
Alan

 

Al, I don't know what converter they used or modified but told me it was a diesel application. Specificlly telling me that, would be a question if it is not fact in some manner.
The reason is the balooning problem.
I assume the diesel units are much stronger in this reguard.
They have custom converters done some place in NYC.
The trans is a 4r70w.
The thing hooks up at about a 1000 rpm.
This shop does things and knows things many other don't and may not tell me full disclosure, as I have no way to verify.
I have no regrets at all about how it operates, runs cooler, shifts quick and does all they promised.
As I understand it, I was the first to have one done in this manner and to satify my use.