Transmission Thermostat Question

[Caman96]

On my 96 K1500 I added OEM cooler this past summer. It’s 30 degrees here and I’ve been driving for over an hour on highway and temperature is steady at 105.

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Now, I’m getting this reading from sensor added at transmission test port. I know this is not the best for accurate temperature but that’s what I got. Does this seem unreasonably low?

 

[Schurkey]

Yup.

The flow may be stagnant at that test port, and you'd have "cold" air blowing on the trans case. So, yes, not the best place to sense temperature.

However, 105 still seems low to me. I'd expect 170+ in the pan, and I bet you aren't that hot there.

Consider re-routing the cooler plumbing so that the radiator tank "cooler" can warm the fluid just before it flows back to the trans. (And/Or blocking off the additional cooler in winter. A scrap of cardboard would do it, even if just for testing purposes.)

 

[Caman96]

I’ll try the cardboard on the way home. Although it’s a bit warmer anyway, I won’t get that 1/1 comparison. But warmer hopefully!