i installed an aftermarket transmission cooler now looking at installing a thermal bypass. the one I'm looking at is tru-cool long brand 180° to install between the factory cooler and the trans cooler i installed. has anyone heard of this brand or can suggest a different one?

The OEM cooler as far as I know has not thermal "bypass" nor does it have a line to bypass outflow back to the inflow line. I'm not a tranny person but I suspect the tranny does not circulate fluid to the cooler until a set temperature point (e.g. it has an internal thermal setting).

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Sold to LOST member my 05 Ltd, GDE Stg II turbo + TCM tune, SunCoast TC w. Transgo kit, Steiger window regulators, Samcos, Fumoto valve, 2nd gen filter head with Lub. Spec. bleeder, Hayden clutch & 11 blade fan, inverted spare, P-1 battery, BF Goodrich Long Trail TAs, Etecno1 glow plugs, timing belt at 50K miles/8 yrs

I'd go to a much lower setting,like 140 degrees.If your wanting to wait till the fluid reaches 180 degrees before cooling,well that can be bad with a stand alone cooler that can't handle temp spikes very well.

A few weeks ago I was in MOAB with a outside temps of 80-85 degrees and temps reaching 120+ degrees on the slick rock and my trans never went past 182 degrees,and I have the same trans as the CRD's do.Plus my KJ weighs 6400lbs and had the AC on and rarely reached speeds over 8-10mph on the trail,mostly at 5mph and less.Factory radiator,in radiator trans cooler that then loops to a 28,000GVWR AUX trans cooler before returning to the trans and no I don't have HD cooling,only the electric fan(3.7 gas KJ).

In any gear and "N" the trans is sending fluid through the cooler.The TCM will not let the trans shift into OD until the fluid reaches like 80 degrees or something like that.No bypass at all in the 45RFE/545RFE.

So...help me out here. Is your trans running too cool? Does your aftermarket cooler have its own fan? Is the fan thermostatically controlled? I would have figured that for anything beyond where the transmission is hot enough to engage 5th gear, cooler is better...

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2005 Liberty Limited CRD; Air Filter Monitor; Samco Hoses; GDE HOT Tune; RL037142AA TC; KJ Interior Rack from All J Products; JBA Adjust-a-strut lift and A-Arms; 245/75R16 Firestone Destination ATs on Moabs; ARB Bumper; ASFIR Skids; FS-2500 Bypass Filter; ARP studs.
2016 Grand Cherokee Overland CRD.