The Stovebolt Site Forums The Shop Area The HiPo Shop Transmission cooler bypass?

Howdy, I have added an external trans cooler and filter to the nose of my '71 C10. The outfit that I got It from, Makco Distributing, strongly suggests a "cooler bypass" for very cold starts. I don't mind adding it if it is really needed, but the original "in the radiator" cooler doesn't seem to need it. Are these guys just trying to stick their hands deeper in my wallet, or do I need to look into this further? My flow pattern will be through the filter then original rad cooler then through the add-on cooler. Comments or thoughts?

Thanks,

Les

I wouldnt worry about it. The way you have it connected up is the best way.
Ive never heard of a cooler bypass before. Im guessing it is for super extreme cold temperatures.
Keep in mind, Heat is what kills a Transmission.

I've heard of engine oil cooler bypass valves/thermostats but never on a trans.
I'm not sure if it would ever get cold enough in NC to warrant fitting one.

Hopefully someone with more knowledge than I will chime in.

I've run and installed dozens of coolers, particularly back when I was in the trailer hitch building business. Unless you're anticipating doing a lot of driving in below-zero temperatures, I see no need for a bypass system. The in-the-radiator "cooler" is going to bring the transmission fluid up to thermostat opening temperature within a short time anyway, so if you're concerned about cold starts, the temperature of the trans fluid will approximate coolant temp on even relatively short trips. Most transmissions can operate pretty trouble-free if the fluid temp is kept below 250 degrees or so, and I don't think there's a low temp limit at all. A manual bypass system can be fabricated with two 1/4" NPT ball valves and a little bit of steel gas line tubing if you want one- - -no need for an expensive kit from somebody!

Jerry

@everyone, Good advice as usual.
@jockbolter50, North Carolina is usually the Sunny South, but we do occasionally get periods that run below freezing for a week or ten days at a time. I don't know what temps are necessary to need a by-pass.
@Jerry, This is the first time that a cooler company has mentioned a bypass in my memory. I did think about using a check valve, like on hit & miss engine fuel system.
@JeffL, That's the way it makes the most sense, and that's the way the instructions suggest! We always wanted to filter oil on a HP Engine when it was as thin (HOT) as possible to get the smallest bits.

Thanks All!