Stacking Trans-coolers

[majek5]

Dieselsite has a Tru-max 4739 trans-cooler that they say they have stacked with a v-10 stocker on their company truck. Claiming that it will pass a flow rate test with flying colors. I had an aftermarket cooler put on mine but want to make sure that temps will NOT be an issue.(30' toy hauler with wife that wants to use it lots!!!) Has anyone done this? Anyone have temp issues with an OBS? If so what have you done to fix it.

[ChuckD]

I have the stock cooler then an aftermarket cooler and in the AZ heat I havent topped 185. Dims are 7x11x1.

[hayjayhorses]

I have the big Tru-Cool 4739 MAX that diesel site offers (40,000 # gvw). I used it to replace my stock cooler. I use it on a ’00 F550 7.3 and I haul loads of hay with a GCVW of up to 45,000 #. I also mounted the cooler in front of the A/C condenser (I feel this is a must). I also put a small tube and fin cooler below the big tru-cooler and I have a fan mounted in front of the tru-cooler.
I use 2 temp gauges one in the tranny line (torque converter temp TCT) coming out the front of the tranny and the other is in the tranny pressure port (PP). I don’t think the pressure port is a good place to monitor tranny temp because no tranny fluid flows by the probe in that spot, also the aluminum is about an inch and half thick in this spot. It should really be in the pan. The next time I have my pan down I will put the 2nd temp probe in the pan.
Anyways on the highway in the summer empty heading to NY (GCVW 17,500ish#) The PP temp would always be 15* to 20* less then engine temp. I have a real ECT gauge, with the probe mounted in the thermostat housing. The PP gauge would run 160* ish. The Aluminum tranny hosing IMHO is a big heat sink for the engine. The TCT would run rite at 140* ish.
Now hauling 10 to 12 tons of hay the temps are naturally higher across the board and the 2 tranny temp seemed to always follow the ECT on the highway. I have seen the ECT as high as 220* (pulling a steep long hill 90*+ outside) and the PP temp would be 195* and the TCT 180* then the ECT would drop to 185 ish in less then a mile with the tranny temps to drop about the same amount a few miles later and that’s with out running the fan. Run the fan and the TCT runs much cooler.
The only place I would see high TCT 220* to 250* is in the yard moving a heavy load or is in town stop light after stop light with a heavy load, so I would run the fan and as soon as the TCC locked up (got moving 25 mph) the TCT would drop fast to 150* or so with in a minuet.
The other time the TCT rises is getting off a highway exit when I am on the brakes slowing down for a long distance (or just off the throttle in an OBS ) the TCC unlocks this create a lot of heat on the TCT gauge, this was an easy fix I installed a TCC lock up switch.
The bottom line is that tranny cooler is really good and should be mounted in front of the A/C condenser if you plow you may want to put an electric fan on the cooler. I also like to have two tranny temp gauges.

TCT= torque convetter temp
TCC= torque converter clutch
PP = presure port
IMHO = in my honest opinion
GCVW = gross combined vehical weight, truck, trailer and load

[majek5]

How did you instal the TCC lockup switch? Any bad side-effects with doing this?

[hayjayhorses]

On my ’00 F550 I put a TCC lock up module from SP diesel, It comes with an adjustable trimmer (allows up to set lock up from 18 to 40 mph) well the trimmer dose not work it locks at 25ish mph. It was an easy install one wire hooks to a speedo wire, one to the TCC wire and the Ignition and ground. I put a switch in the TCC wire so I can shut it off.

It works well I don’t use it too much now that I have a max low stall billet multi disk torque converter. This new torque converter was a great upgrade less than $500 Ford Heavy Duty Torque Converters by Precision of New Hampton, Inc.

The only issue is the “OD OFF” light will flash when is commands NO lock up and the TCC solenoid is still grounded. But no limp mode.

On my ’97 I just put a switch with one side grounded and the other going to the TCC wire you just need to shut it off when you come to a stop. I needed to do this with the ’97 because I need to lock in 1st gear.

The reason to manual lock in 1st is because the road to my farm is rough and windy with a one steep hill and when pulling hay or horses I cannot get a run up the hill so I am in 1st gear full throttle for about 1 mile.

The OBS truck will not lock up in 1st gear (SD dose at 75% + throttle). With out lock up my TCT is at 250* to 280* by the time I get in to my driveway. If I lock TCC and pull the hill (no need for full throttle) the TCT is 140* to 180*

I have read it is not good to lock in first but I never do it at low RPM

The lock up switch will really save a stock converter IMHO

[majek5]

Does anyone know how much fluid the trucool 4739 holds?

[hayjayhorses]

Originally Posted by majek5

Does anyone know how much fluid the trucool 4739 holds?

like a pint, not much it is a stacked plate cooler