Trans cooler again?
 

It all depends on what type of transmission cooler you bought and where it was installed..

DUB

It's installed right in the nose. B /M.

Ouch! $500? You must have bought the gold plated super duper, not available in any store model. Those coolers are an easy install if you have somebody to help you remove the hood. Hardest part is getting at the Rad cooler line on top. I still think you should have not by-passed the rad, but its your tranny.
I installed the small and thin 3/4" B&M unit also. But the fluid runs to the rad first, then the cooler. I noticed an immediate reduction in antifreeze temps by 10-15 degrees.
Go figure.

Well that's the insalinstall. include. And I think that it was more like 400. But it still should still run cooler. If you bypassed the radiator.
thanks
John.

Hi,

Was the thermostat getting its signal from the transmission pan or a line near the cooler?
I have a gauge with the sensor in the pan and use an adjustable fan controller thermostat that you can set at any temp you like or change it with the seasons.

John

I'm not sure. He told me that it was set for 150°. But he said that he moved the senser. But obviously not. That's why I told him to put a toggle switch in the dashboard, so I can monitor it. So that's what he's doing. Like I say I can drive at 180 all day. But! I want it to run at the temperature that I want. I can't believe the hassle. These guys work on monster trucks all day and every day. What's the problem.

Thanks
John.

Ok..I have a number of questions.

I see that you have a 383 which is essentially a 350 with a longer stroke crank so that should not be creating any heat issues for you other than a standard 350.

You mention a B&M cooler..double stack and what GVW rating??//24,000/28,000?

you mention that the cooler has a fan attached? I am assuming that you are using electric fans for the radiator cooling thus the need for a separate fan on the cooler? With a mechanical fan, as long as the cooler is in the air flow you would not need a cooler with a fan attached.

All of my DD drivers with stand alone coolers have electric radiator fans that do not run all the time and none of these cars run any where 150 degree tranny temp under normal driving and ambient temps less than 90 degrees which leads me to believe that the cooler you have does not have a high enough BTU/GVW rating. My cars with coolers and electric radiator fans have:

Chrysler 300-28,000 GVW Long/Dana Cooler

1994 Mustang GT 42,000 GVW Long/Dana (1 24,000/1 18,000)

2001 Pontiac Grand Prix-36,000 GVW Long/Dana (2 18,000 GVW Coolers)

What auto transmission is in the car? With the correct sized cooler in the car and a double stack type like my Long/dana with automatic temperature control built into the coolers, you should be easily be able to run sub 150 temps in the tranny. I have run stand alone coolers for 35 years and have never had a tranny failure.

Have you verified the tranny fluid temps with an infrared thermometer on the cooler lines in and out as well as the temp in the pan?

I agree with all what was written in POST #8.

I know you said is it installed 'in the nose'. But knowing the 1977 Corvettes. There is not a lot of places it can be put where the cooler is in a direct stream of air flow..

I can say that when I work on my truck or friends trucks they are much easier to wok on than Corvette in most cases. Much more room and freedom to be able to put 'things' due to the increased space. Heck..I can slide under my truck and do not need to jack it up. NOW. This does not mean that getting a system to work is that much different and getting it to work proper is harder...but changing up on what they are normally accustomed to doing every day may cause for some final 'tweaks' to the system to get it to the way you want it that they normally do not have to do or deal with. None the less.. I would NOT have given your car back to you until I achieved the temperatures you requested. THAT is the only fault I can see. AS for the price...Anybody can comment on how much something should cost...but unless they are doing it or we can see how well they did the installation I can not comment on the cost...because sometimes custom projects like this can cost this much.

DUB

Thanks for the great! Knowledge. The mechanic that insalinstall the cooler did a great job. He removed the hood then had to do some fabrication. The yrans is a TH 350. Heavy dudy cluches, shift kit,and a 3500 stall. I just want it to run cooler. That's it. Very simple
We'll see what he comes up with. Sure I can run 180° all day. But I didn't pay to run 180°. I could have done that without putting a trans cooler on. At the strip it's gonna run too hot.
Thanks
John

Just fyi about trans temperatures and drag racing - I have a "built" TH350 trans, 3,000 stall with a trans cooler mounted on the front of the radiator (no A/C). I have the stock mech fan. My cooler is in series with the radiator trans coil, so my trans fluid is always right around engine temperature. I bracket race my car occasionally, sometimes with some success, so at times I am making runs with very little time in between - but I always try to have my engine at 180* as I am staging.
I have a 383 also and my car currently runs in the 12.2 to 12.3 range. I have about 230 runs on the trans with one rebuild just for general maintenance. The trans internals were good at that point. My fluid stays so clear it is hard to see it on the dipstick.
Obviously you can do what you want, but this might give you some peace of mind.

Seems to me that all you need to do is get a different switch that turns on at 150*. Shouldn't be that big of a deal. They make adjustable switches.

Thanks for the info. Actually I'm having them put a switch in the interior,so that I can control it..
thanks
John

If your cooler is the B&M #70297 with the fan, the thermostatic switch for the fan on temp is 175*.... So the fan isn't going to come on before that...regardless of what they did. Your options are try to find a lower temp switch, or just run the fan on a toggle switch.....or just wire it to a 12V switched source so it stays on all the time and you don't have to worry about it.


I used to run that same cooler on my C5Z and RARELY would the fan ever come on.... Without the fan on, the trans usually ran 160-170* unless I was in BAD traffic...and that was with a 3800 stall. Most of the time, it would be in the mid 150s when cruising without the fan. I did bypass the radiator. Cooler the better for auto trans....but...there is nothing wrong with 180-190* temps...it'll last forever like that. Its when trans temps get in the 220-230* range you need to worry.

Many years ago I built a 200 4r for my '72 vette, FI 350 engine, obviously computer controlled, aluminum radiator, and new condenser.....dual Spal fans for many years now.....

On a trip to a junkyard I pulled a engine oil cooler from some truck, and so i't about a foot square and about 1.5 inches thick, it keeps the trans at ~130f easy....even on a 100f FLORIDA day, off the freeway, and into traffic.....a/c running or not......fans turn on at ~180f if a/c is not running....cooler installed between radiator and condenser......

John, it sounds like you've gotten some excellent advice, so I'll just add one point I don't think has been fully made yet. Back in the early 70's I worked in a shop while going to college run by a couple of engineers whose day job was running the test cell at the Mobil research facility where they were then developing and testing Mobil 1 oil. Therefore when they talked about lubricants I tended to pay close attention. The general consensus back then was that lubricants, in particular engine and automatic transmission lubricants, needed to reach at least 180° to rid themselves of condensation.

What does your transmission guy say he considers a normal operating temp for the transmission fluid?

Good luck... GUSTO

The topic of temp comes up all the time. The biggest killer for trannies are dirt and temp. There is no such thing as too low a temp for tranny fluid as long as the temp is above around 120 degrees. Dig deep in tranny temps and you will find the ideal temp is around 140 degrees for longevity but difficult to achieve in real life driving even with coolers. All my cars run less than 150 degrees tranny temps and this temp going back to the early 80's with my Nova ss and the turbo 350 trans.

Run the lowest temp less than 150 degrees, change the trans fluid/filter often (no more than 20K miles) and you will have a tranny that will last seemingly forever.....condensation has NEVER been an issue in 35 years of using external tranny coolers and low tranny temps-NEVER!

Changing the fluid often and running low temps is MUCH more important than any concerns around condensation.
My 01 grand Prix with 2 Long/Dana 36,000 GVW total cooling in all weather including sub 0 temps just passed 210,000 miles on the crap FWD 4T65E tranny which is NOT know for longevity.

I am really amazed that much misinformation circulates around the transmission cooler issue and tranny fluid temps.....Reminds me of the nonsense propagated around new cars and lifetime transmission fluid...HOLY CRAP--NO!!!!! There is No such thing as lifetime fluids!!!!