Tranny temperature

[junker39]

Just curious as to what is the best temperature to run this C-6.(stock converter) The gauge never gets off the 120 mark. I've got a big cooler mounted in front of the radiator so it's possible the fluid is staying that cool. I'm fairly sure I have the sensor mounted on the pressure side line. The lines feel warm but, not hot, after running down the road. I didn't know if there's an optimal temp for a tranny or not. It could be my gauge is bad, too. Thanks.

 

[Yankee Transplant]

dont know but I would like to know . I have a 350 turbo and it dont have a cooler in the radiator but it had an extra cooler below the radiator looks like it may be about 6" tall and about 12" long .. I have it run threw it now .. I dont think this will be enough . I 'm no mechanic . i'm just a part swap-per ...I may have to get a larger one to place in front of the rad .

 

[tmgant]

I think with a cooler that large, it is what the gauge says. do a test block off the air flow of the cooler and see if temps go up. Tobby

 

[Dr Crankenstein]

Your cooler is an AC condenser?


.

 

[donsrods]

Interesting question. I know motors need a certain amount of heat to keep them running right...........so the condensation burns off, good combustion, etc, but not sure if that applies to transmissions. I do know too much heat cooks transmissions, so you don't have that problem for sure.

If I had to guess , it would be that cool is better, so you should be ok.

Don

 

[junker39]

Thanks for the input. I was kind of thinking the same Don. I've never heard of letting a trans "warmup" before running it. I just didn't know. I don't want to screw up this transmission. It's my first to rebuild. And it actually works good. I may throw some cardboard over it and see what the gauge does, tmgant. Good idea. Doc, no, it ain't a a/c condenser but, I have used them before. They work good. This is a tranny cooler that came with a rebuild from a trans builder. I think it was a for a one ton Chevy with an Allison. The truck already had one so I got a little bonus out of that job.

 

[BlueNorther]

I was told years ago when buying a cooler for my tow rig, that after a warm up period, an idle temp between 175f and 225f was good and under load it should be between 225f and 275f, and MUST NEVER GO OVER 300F.

The tranny guy said every time the atf goes over 300f it cuts the life span in half.

cooler should be inline with a cooler in the radiator. the built in cooler in the rad also acts as a warmer in the winter. running the atf too cool is as bad as running too hot.

 

[Bamamav]

What Blue Northerner said sounds right to me. I know in the Freightliner, the manual trans usually runs 180* to 200* year round.

 

[sgtpontiac]

As an OLD trans guy...

trans temps really shouldn't exceed engine temp....ever....usually they are 15 to 30 degrees cooler and even more if running a trans cooler.....the cooler it runs then better off it is up to a point..it has been recommended that on cold days you allow the trans to idle in neutral to et all the fluid to get to the areas it needs to lube prior to just throwing it in gear and putting the hammer down....lol...
as an example...my suburban runs 210 engine temp and 180 trans temp....that's about normal....yesterday driving to visit my daughter it was 210 engine temp and 162 trans temp at the highest....for whatever it's worth....

HEY...ALL MY ICONS ARE SHOWING NOW....!!!!!!!!!!!

 

[30sx]

googled this from a transmission exchange co. ad.......this is the expected trans life at each temp.....325-500 miles....300-1500 miles...275-12000 miles...250-20,000 miles...225-40,000 miles...200-80,000 miles...175-100,000+ miles[cl

 

[junker39]

Thanks everybody. Next time I get it out, I'll try the cardboard thing. It's possible I'll have to run it thru the radiator to heat the fluid back up. That cardboard will probably make my engine coolant temp go up and that doesn't need to happen. Thanks.

 

[ssimpala]

You're fine just as it is. This summer it will run warmer.

 

[RPM]

My Chevy truck came from the factory with a trans temp gauge. Pulling 12,000 lbs up a mountain and it never goes over 170.

 

[junker39]

Ok. One way or the other, it looks like it needs to stay around 160-175. I can manage that either going thru the radiator after the cooler in the winter and before the cooler in the summer. I've got a two way, dual line valve, somewhere. It'll be trial and error. At least there's a place to start. Thanks.