I have a 93 One ton dually with a 4L80E transmission.

I just installed my transmission temp gauge and I have to say that I am frightened by what I found. I had found this on my 82 Scottsdale as well with the 700R4 in it.

How do these transmissions last? I put a guage in my 82 and was shocked to see temps spiking into the 300 degree range! Everything on the truck was stock and the radiator had just been recored and a new transmission cooler on the side! I installed an auxilary cooler to that and I was able to keep the temps around 170 all day long then.

I installed a digital gauge in my 93. It spikes above 280 degrees and then just starts flashing HI across the screen! Again, everything is stock and the radiator looks like it was replaced not too long ago.

How can these trucks last with transmission temps like this?

Anyways, my cooler question. This truck has the 454 in it. It works hard. It tows hard. The water temp gauge on the dash already reads a little over 210 on hot days when towing. I really don't want to add yet another thing onto the front of my radiator. It already has the radiator and then the AC unit. But, I know of no other place for an auxilary cooler.

If I go in front of the radiator, would there be any benefit to having a cooler with a fan on it? This thing is a 10,000 GVW vehicle and it has been known to tow upwards of 20,000 pounds in one trailer. I want this transmission to last as long as I can so the cooler I can get it, the better. The only benefit I could see to the fan would be if you are stuck in traffic at an idle. But what are your thoughts on this setup?

If you are going to mount a cooler with a fan, then mount it off to the side or under the cab. The cooler has afan to move the air and does not need the vehicle or engine fan to cause air to maove across it. Just mount it where there is plenty of air space and then drive the truck.

./agree

I put the biggest cooler on my th350 I could find when I put it in my s10 Of course what I have is probably overkill but I tow a trailer all day and didn't want to burn mine up either.

Question how many core is the radiator? AC? 210 seems a bit hot even towing and maybe consider a slightly smaller thermostat, or even a different fan on that puppy?

Everything I read says tranny temps over 250 and the oil starts to breakdown and frankly with time it took me to put that th350 in my 98 s10 I surely don't want to do it again. Right now with air temps of 83, I still run cool enough on the return line of the tranny that I can touch it without burning myself.

The radiator is HUGE! It is in a one ton dually with a 454 and I think it is actually bigger then the one that was in my 82 that originally had a diesel. It has the oil cooler on one side, the transmission cooler on the other, it appears to be made of aluminum and it is 4 cores. It does have A/C but it doesn't work right now and I haven't had the amhbition to find out why.

I honestly think the gauge is off rather then the temp. I have known stock gauges to be quite a bit off. I usually put my sending unit in the intake right by the thermostat. I believe that this sending unit is right in the cylinder head so it is going to read hotter to.

The red area on my gauge in my truck isn't until something like 280. I haven't tried an external gauge, but I am pretty sure that it is just the gauge in the truck. The radiator looks pretty new inside and out.

I just bought a cooler that is rated for a 40,000 GVW. It also has a thermo bypass so that the oil doesn't stay too cool. It keeps the oil from flowing through the cooler until it reaches a certain temperature. This will help in the winter time around here where we can see 20 below air temps.

LOL yeah in fla I don't have to really worry about cold temps :P

LOL In North Dakota we get anything from 100 + temps during the summer to 20 and lower below in the winter. We have the best of all worlds! :) It's amazing vehicles last as long as they do in these areas. It is always such a change. It's sad when you go to work with the heat on, go to lunch with the windows open, and go home with the air conditioner running. :lol:

I put Mobil 1 in my tranny.....it doesn't break down as fast.

Size the tranny cooler correctly. For your 1ton towing a bunch of weight, the biggest cooler you can get is the best. I had B&M's big one with the 1/2" outlets on my 2004R in a 79 1/2ton. In arizona winter the tranny would be around 90* at hottest. Thats a bit too low probably.

Well, I got the cooler installed for now. I need to get my bypass valve in though. It has been around 40's to the 50's here since I got it done. The transmission has only reached about 130* and that was getting off the interstate, idling at a light. Otherwise it is running about 100 to 120*. I have it leaving the transmission, going into the radiator cooler, and then going out to the external cooler and back to the tranny.

Once I put my bypass in, it will go from the tranny to the radiator. Out the radiator into the bypass. If the oil is too cold, it will then just route it back to the transmission. If the oil is hot enough, then it will allow it to flow to the external cooler.

I think it should work. What do you guys think?