Does anybody else notice the extreme difference in performance of the 4R100 between cold and warmed up? In fact, I don't beleive my trans every really gets up to temp when its below freezing outside.

My brain is a little fried after spending the whole day in the garage, but basically it seems to just hold gear for ever and is very unresponsive to driver input. When its extremely cold out it never really seems to act right, but normally after somewhere between a short and long time it'll get back to acting properly.

I know this is a terrible description but I figure if this is either normal or common then somebody will know what I'm talking about

 

I think what you are feeling is the torque converter not locking up. This is normal until the engine is at least 160-170 degrees. The trans feels like it is holding gears, but it actually is not---It's the converter slipping.


RON

 

Sure could be. Its definately a different truck for a lot longer then it takes the engine itself to warm up.

 

Yup, there's no thermostat on these things from the factory, the 5R110 was the first SD tranny to get that. When I installed my 6.0L cooler I also put in one of these:

https://www.ford-trucks.com/forums/1...tallation.html

Now I see 170-180° transmission temp year round!

 

Installing the radiator "cooling" that was added in 2000 might actually warm up transmissions in these cases...?

 

It doesn't work like that, it's a myth that just won't die!

The oil-to-water cooler is located on the cool side of the radiator, and after passing through the entire radiator the coolant isn't ever at a point where it's warmer than the transmission fluid. There is no point in time where the transmission fluid is EVER warmed by the engine coolant.

 

( Somewhere, Mark K is smashing a keyboard to pieces right now. )

 

So at least ONE person reads what I write!

 

There are a few of us actually.

 

Well at least 3

 

<~ #4 here

 

I have a Kovalsky shrine set up in the garage...the wife just doesn't get it.
Yes count me in as a listener Mark. After 50 years on this spinning ball of dirt I have learned at least two things... I dont know it all and shut the pie hole and open the ear holes... OK technically that's three.
Now if I can just get you to stand over my shoulder when I tear into my TS to find that elusive 3-5 bump slide (only when warm and then intermittent. My favorite thing to TBL shoot intermittent!).
<quote...the oil-to-water="" cooler="" is="" located="" on="" the="" cool="" side="" of="" radiator,="" and="" after="" passing="" through="" entire="" radiator="" coolant="" isn't="" ever="" at="" a="" point="" where="" it's="" warmer="" than="" transmission="" fluid.="" there="" no="" in="" time="" fluid="" warmed="" by="" engine="" coolant...end="" quote="">
Crazy001...Just think if that cool side ever got hotter than the trans that engine would be in a world of hurt if it didn't lock up before that.</quote...the>

 

I think there is a I like mike thread, Maybe we need a I like Mark thread if there isnt one already..

 

I understand completely.
My SWAG on this is a sticky solenoid. New fluid might fix it.
Sounds good to me!

 

Way to go guys, we gave Mark a big head...