Transmission Thermal Bypass

[jsb5717]

So, the transmission thermal bypass. Has anyone done this? After coming across MANY YouTube videos on the topic I decided to install one on our RAM before taking off a week ago on a 2 month trip. I don’t know if all of the OEM’s have a thermal transmission valve, but the RAM’s do and it’s apparently a potential source for costly tranny overheating.

As I said, there are many videos on why to do it and how to do it. It’s a fairly simple thing to do. I bought the ATS bypass kit and swapped out mine in about 20 minutes.

On previous towing trips the tranny temps would average about 175 deg and fluctuate up from there with longer uphill pulls. So far on this trip we have pulled some pretty aggressive hills including going south on I5 north of Grants Pass, OR and also the pass over the Siskyous. The tranny temp is averaging much lower…around 130 to 150 degrees and have gotten as high as 170 degrees a couple times, and not for very long.

Anyway, I’m just curious of other experiences with the thermal bypass and results.

[ScottnSue]

Howdy Jeff, I've been seeing a lot of those videos as well. My truck is older so it has the transmission thermostat built in to the cooler. What gauges are you using to monitor your transmission temps ? Does your truck have the Aisin or 68RFE ?
We're looking at 2015-2018 Ram 3500's but seems most have the 68RFE.

[jsb5717]

The newer trucks have all of that monitoring in the dash. There are multiple screens I can scroll through so there’s more than one way to see the tranny temp. When I’m towing one of those screens is always in front of me to quickly see critical temps.

Yep, it’s a 68RFE…most of them are. There are tons of videos on this tranny and how to upgrade/improve its life and performance. I haven’t done anything to it except this thermal bypass. I don’t know if I’ll do other upgrades and this truck is just at 50k miles. I’ll keep on top of regular maintenance items and see if more is needed down the road.

[rvman]

I also did the thermal bypass and noticed a significant temperature drop inline with your observations. The 68RFE is a good transmission if you treat it right. Forget the aftermarket tuning for more power unless you are willing to dig in your wallet and have the trans "built". Heavy towing only in 5th gear and below and manually shift down on the hills to minimize "flare shift".

[Karanmatt]

I installed one on my 2017, man what a difference when all the transmission fluid goes through the cooler rather than just a portion. Not about all the debate of good or bad, just makes me feel better tugging our 2007 3295RK.

[TennTom]

I bought one from ATS for my Aisin, just have not installed it yet. Never liked the idea that the fluid coming from the TRQ converter goes through the xmsn before getting filtered. That's where most of the crap comes from. How much fluid did you loose changing it out? Just a burp or more like a pint?

[jsb5717]

Originally Posted by TennTom

…How much fluid did you loose changing it out? Just a burp or more like a pint?

I think it depends on how much effort you put into blocking the line to minimize loss. I slowed it down with a make-shift plug and lost about 1/2 quart.

[TennTom]

That's what I was thinking. Thanks.