That’s my thought as well, same temp as the engine. Have you compared the engine and trans temps at the same point in time?

Rudi wrote:

That’s my thought as well, same temp as the engine. Have you compared the engine and trans temps at the same point in time?

As a matter of fact, the two reads are right next to each other on my laptop, Rudi.  With the engine at 194 the trans was at 192.  Coming home the engine ran 196 and the trans was at 198 - 202.  I do not have an add-on trans cooler...just the little POS in the lower tank of the radiator.

When the trans cooler is in the radiator tank it shouldn't surprise anyone that the trans fluid temp and the coolant temp are the same.  I wouldn't worry about 190-200 degree trans temp.  Oil needs to be at a certain temp to do its job properly.  That temp is about 160-210 degrees.  Below that it doesn't flow right, and above that it gets thin and can burn. 

A dedicated trans cooler is never a bad idea.  Especially if you run on the highway a lot where trans fluid temp can cause the coolant temp to increase. 

Bob, does the 4r70w have direct in/out in overdrive the same as the AOD?

Thanks Bob, it is all good information to have. I agree the 4r70w is a more modern version of the AOD and its shift points can be set easily.  Bauman has a shift kit for  the AOD but will increase the 2-3 shift by 18% which for my use is too high for my rear gearing, it also takes the 3-4 higher as well but not as much. My AOD was built with all of Bauman’s recommendations on his web site, I see they no longer support that model other than their shift kit.
The issue I have with the AOD is the dreaded 1-2-1 shift to hold 3 gear for as long as you want before going into OD. There are a couple of valve bodies that cure the that issue but for 600 usd I will live withe the status quo.
I like that the AOD locks out the torque converter in OD,  that alone should reduce tranny temps on the freeway.

I forgot to add that I am using an external transmission cooler as well as the one in the bottom tank of the 24” Champion rad.
The fluid in the transmission still has the colour as it had in the beginning, I don’t have a TI on it.

Rudi wrote:

Thanks Bob, it is all good information to have. I agree the 4r70w is a more modern version of the AOD and its shift points can be set easily. Bauman has a shift kit for the AOD but will increase the 2-3 shift by 18% which for my use is too high for my rear gearing, it also takes the 3-4 higher as well but not as much. My AOD was built with all of Bauman’s recommendations on his web site, I see they no longer support that model other than their shift kit.
The issue I have with the AOD is the dreaded 1-2-1 shift to hold 3 gear for as long as you want before going into OD. There are a couple of valve bodies that cure the that issue but for 600 usd I will live withe the status quo.
I like that the AOD locks out the torque converter in OD, that alone should reduce tranny temps on the freeway.

The AOD Shuffle Shift on mine is to control the 1-2-3 shift.  My AOD had three detents.  The first (forward on the shifter) makes it go through all four gears (I used the C4 green dot for that.  The middle detent will make it shift as a C4...1, 2, 3.  As long as I leave it in the center detent  it will never to into OD.  One nudge forward and it goes into OD.  The shuffle comes if I pull it into the third detent.  At below about 12-15 mph that puts it in 1st.  Above that speed a nudge into the center detent makes it go to 2nd and if it's immediately pulled back to the third detent it will hold in 2nd. Then a nudge forward again makes it go to 3rd and another push forward makes it go to 4th (OD).  I know that Terry's AOD is the same as mine as I've been his car when he showed me how it would bark the tires on the 1-2 shift.

 

Yes, the external cooler should never be divorced from the radiator completely.  Just plumbed into the return line. 

Worth noting to always replace the external cooler if you have a trans grenade.  They get clogged with junk that can then ruin the new trans.  The lines can be flushed, but not the cooler. 

50vert wrote:

Bob, how hard was the shift schedule to setup? Does your data speedo match your actual speed?
I'd much rather pickup the hat in person, but that's not gunna happen anytime soon.

My speedo is about two MPH faster than the OSS.  Following Decipha's instructions for setting up the shift schedule was pretty easy.  You just calculate a number based on tire dia. and rear gear ratio and come up with a number which divided into RPM in third gear equals speed.  The PCM then uses OSS and shifts per the shift points you enter for each shift vs Relative Throttle Position and RPM.
On light throttle it does 1-2 at 10mph, 2-3 at 20 ish, and 3-4 at 35.  Under hard throttle It would pull all the way to 5K, or higher, if I let it.  It does seem to "flair" a bit on harder throttle but I think a little tweaking will fix that if I'm worried about it.  I'm running it in the stock "Dynamic TV Pressure" mode where the PCM calculates torque from MAF airmass.  This can be changed by changing a Scalar and loading TV pressure values in tables for Forward and Reverse.  I might try that mode just to see how it works but right now I'm pretty happy.
I do have had a problem with TC Lockup not holding in OD.  It locks and then looses the lock signal after about five seconds.  Third gear works as it should. Decipha asked me to post my Tune which I did last week and this morning he posted a revised Bin for me to try.  Car is at a friend's place getting new tail pipes  so I'll try the new Bin soon as I get it back....Let you know.

Last edited by Bullet Bob (4/20/2021 8:14 PM)