Transmission thermal bypass valve

[gemarsh]

Follow-on comment and concern with those running the PPE bypass just as I am. 2025 3.0 with 10L80.
I'm seeing a 50-60* transmission temp delta from ambient temp. Meaning if it's 80 outside, the trans temp holds around 130ish. But now that it's cooler out, weekend trip started with 50* ambient and trans only reached 110* . That seems way too low. What happens when it's 0* out and I only see 60* on the trans temps? Thoughts?

PPE's response was to pull the bypass out in the winter. Seriously?!?

Yes, unfortunately that is how it needs to be done.

Unless you happen to live South, but ya don't, if'n your asking about 0°F!

The cold is coming, don't forget about diesel treatments!

 

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[sanny651]

Follow-on comment and concern with those running the PPE bypass just as I am. 2025 3.0 with 10L80.
I'm seeing a 50-60* transmission temp delta from ambient temp. Meaning if it's 80 outside, the trans temp holds around 130ish. But now that it's cooler out, weekend trip started with 50* ambient and trans only reached 110* . That seems way too low. What happens when it's 0* out and I only see 60* on the trans temps? Thoughts?

PPE's response was to pull the bypass out in the winter. Seriously?!?

I don't know if the original owner of my truck (it was leased I believe) installed the dumbbell in my valve or if the stat is stuck open (defect) from the factory. I think the latter, but regardles....my truck rarely ever gets over 175F, and that's with hauling my Ice Castle in the summer. It'll get to 190F if I'm doing hills with it, but that's expected.

I also haul my Ice Castle extensively in the MN winters, and it's usually around 130-140F. I'd wait to see what it does, but based on what GE Marsh says, it sounds like it's par for the course? I would also check to see if your louvers are working too. If they are stuck open, that'll further keep things cooler

 

[sanny651]

Yes, unfortunately that is how it needs to be done.

Unless you happen to live South, but ya don't, if'n your asking about 0°F!

The cold is coming, don't forget about diesel treatments!

I've driven in air temps of -40F....so things get "brisk" here in the winter. -40F is pretty uncommon for MN, but -25 to -30F is definitely not uncommon, and I drive hauling my ice castle in that all the time. I'll have to keep a closer eye on that, but historically speaking my truck did well in those temps with trans temps

 

[Craneman1]

Hey all,

I just saw a transmission cooler bypass kit today whilst snooping around the intergoogleweb machine. Has anyone done this with the 10 speed transmissions, and does it in fact help it run cooler? I saw a video where a guy installed it and it ran about 25F cooler (190F down to 165F).

So has anyone done this mod? Any cons I should be aware of? I don't haul a lot during the summer, but I do haul quite a bit in the winter here in MN. Never saw the trans get over 200F to my recollection, but have seen it in the 190's.

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I have been running the PPE bypass valve for over a year.
Alabama has some hot summers. Trans temp rarely gets over 165 degrees.
I have a family member that owns a transmission shop and he says the valve will definitely prolong the transmission life span.
It greatly reduces the temps.
Well worth $80.00 to me.

 

[Holy Smokes]

I have been running the PPE bypass valve for over a year.
Alabama has some hot summers. Trans temp rarely gets over 165 degrees.
I have a family member that owns a transmission shop and he says the valve will definitely prolong the transmission life span.
It greatly reduces the temps.
Well worth $80.00 to me.

For higher summer ambient temps I 100% agree. But with no means to thermostatically control flow in cooler climates it does not allow the fluid to warm up enough.
It’s too much of a hassle to swap out twice a year.

 

[F32_Sierra]

I had done the Mishimoto bypass on my 18 Sierra (8speed) a few years back when my OEM thermal valve failed on me in the middle of the desert.

After removing it, my new operating temp went from 200°F to about 150°F. Shortly after I installed the Mishimoto Trans cooler (+1Qt) and operating temp still stayed around 150°. I live in Arizona so temps rarely get below 40°F so no concerns from me regarding weather. Even hauling 12k lbs on a sunny day where our asphalt can easily reach 160°F +, the temps never went above 180°F after my bypass.

I couldn’t recommend it enough for my climate.