Upgraded trans cooler

Hmmm....so on a 4hr drive over the weekend, 85 outside temp, 70-75mph...my temps held steady at 217 pan / 219 converter; not towing anything pretty much flat hwy...2020 SR5-TSS package. What should normal temps be or is that normal?

 

Forgot to mention....drove in "D" with no Tow-Haul

 

@bmf4069

 

Have you seen the threads about Toyota ditching the transmission coolers starting in 2019? A lot of people on here are pissed at their decision. I would not be happy with my truck consistently running over 200 all the time. That's going to lead to unnecessary wear and tear.

I would jump over to the 3rd gen section to get more relevant info on your 2020.

https://www.tundras.com/threads/2019-2020-transmission-cooler-missing.72484/
https://www.tundras.com/threads/19-20-discussion-on-missing-ambient-cooler.73176/#post-1876176

 

Not sure what the newer gens run temp wise but ideal trans temp is 170* +/- 25*.

My other truck (2016 2500HD Duramax) on a four hour drive only would get up 140. Obviously a completely different truck setup for towing from the factory but I thought it was interesting anyways.

 

For clarification, I'm going to ditch the overdrive terminology (because the gear ratio of the tallest gear isn't germain to this conversation) and say our trucks have a 4 speed transmission with a locking torque converter.

When you put the gear selector in "D" with the OD Off not selected, the transmission shifts 1 - 2- 3 - 4, then locks the TC. When you press harder on the accelerator requiring a downshift, the TC unlocks and the transmission shifts from 4th to 3rd. If you remain in 3rd at about 45 mph and depress the OD Off button, the tranny stays in 3rd gear, but the TC locks back up. So the RPM will actually be lower with the OD Off activated than if it was not activated.

If you start from a stop with OD Off activated, the tranny will shift 1 - 2 - 3, then lock the TC.

That's why it's benefitial to activate OD Off when towing: it allows the TC to lock in 3rd gear -- which wouldn't happen if OD Off was not activated.

 

I’ve got an ‘05 and it is definitely a 5sp auto. Gear ratios are:
1st - 3.52
2nd - 2.04
3rd - 1.40
4th - 1.00
5th - 0.72

 

Does the scenario change if one is gling 65 instead of 04? I can promise you my RPM's are not lower when I press that button at 65.

 

I would assume it's not the same at 65 mph because the engine and transmission are loaded much differently in that scenario. I don't know the intricacies of this transmission, like the shift points and the electronic logic controls -- for instance, is there an RPM threshold over which the TC won't lock? I'd love to see those specs if they were available. I do understand generally how they operate, and how to recognize what they're doing and when they're doing it.

 

The FSM is pretty good at explaining the shift to RPM ratios (throttle position). There is even a nice chart. I put it up a while back in another thread.

 

Thanks.

I’ll have to dig that up.

 

@SouthPaw and others, when you added the Hayden and Derale, did you bypass and cap off the trans lines to the factory radiator?

 

Nope, only replaced the external cooler but kept everything else OEM. For anyone considering this, Hayden has recently released a cooler with a built in fluid controller. If I had to do it all over again, this would be the route I’d take.

https://www.haydenauto.com/en/produ...oil-coolers/patented-internal-by-pass-coolers

 

I may have just missed it, but I'm not seeing the by-pass temp. Is it 180, like most?

 

So this eliminates the need for the thermostat you added?

 

By-pass vs thermostat, pretty much the same things. To answer your question, yes.

 

Si.

I didn't see it but I assume it's at 180*.

 

So far, I’m coming to the conclusion that a new cooler is not necessary for me in HOT weather so much. Even when towing long distance the temps are not bad. I really like the idea of the cold weather automatic by pass built in (or even the thermostat option) which helps the transmission come up to temp quicker in winter.

My original doubts were the cooler making things too cool. The bypass/stat option sound like a winner. Better for MPG in winter I bet with the trans fluid getting warm quicker helping with friction.

 

just something to show.. but it would appear CSF makes an trans cooler thats a bit beefier that bolts right in.
https://www.carparts.com/details/To...ShPGRSkLjI5-m0tmddRoCRcEQAvD_BwE&gclsrc=aw.ds


totally just going off photos. but it would appear this is the case.

 

Who is going to be first?

I’m still extremely happy with mine especially on the cooler mornings. Trans warms up quick and it never hits above 185*. I’ll probably eventually make some mounting brackets for it but it’s been working great.

 

I might for the hell of it. The rebuilt trans in the f-350 is likely going to get the 30k cooler now that It’s got a $3000 built trans.. lol

 

No trans cooler for a DC?

 

No love for DC* lol

 

Well since my custom radiator has noticeably dropped trans temps I ordered the factory trans cooler lines and am going to run the stock cooler I picked up cheap. Probably end up ordering the CSF

 

Hey guys,
I know I'm resurrecting an old thread. My truck is a 2006 with 4.0 V6 without a towing package. I went through this thread and I didn't see anyone installing a cooler on a truck that didn't already have the towing package. My question is, Does my transmission already have hookups for a trans cooler? Do I have to install new lines from the trans to the cooler? If so, how do I install those lines?

 

I'd be surprised if you don't have the lines already running to the radiator. If you have those, you can put a cooler either before or after the radiator. I don't know which is beast.

 

I'd think after the radiator would be best for maximizing getting cool fluid to the trans.

 

Thanks guys,
I will check for some lines coming out of the trans in the morning. Does the trans need more fluid after I install a cooler?