Tranny Temp

[marktara]

Those of you with tranny temp gauges, how hot will a 4l80 get when pulling hard with just the aux tranny cooler that comes with the trailer towing package? Just trying to figure out if I need another cooler with the fan on it to pull a 6000 to 7000 pound fifth wheel

[96ccdd]

I HAVE MY SENDING UNIT IN THE PAN AND WHEN PULLING MY 7500# TT TRANNY TEMP RUNS RIGHT AROUND ENGINE TEMP MAYBE 15* HIGHER.

[Dvldog 8793]

Howdy
My sender is mounted in the pan. MAG Hy-tech 3 extra quart and ALL mobile synthetic ATF.
Pulling my trailer with a 6500Lb ASV on it with ambient temp of 70-80deg I NEVER see the high side of 150. The pan and fluid made a about a 40deg difference.
L8r
Conley

[Bill Voitel]

Keeping your trans as cool as you can is one of the best things that you can do to extend life the info to follow comes from Hayden Automotive (aux cooler mfgr)
220deg fluid additive package starts to break down
240deg varnishes strart to form
260deg seals start to harden
295deg clutch plates (packs) slip
315deg clutchs burn carbon forms

regular maint (fluid & filter services)& aux coolers and syn fluid should get you lots of miles out of the 4L80-E units most of our trucks have.

Bill. :cool:

[Uncle Wally]

With my truck bone stock with the exception of the cooling upgrades and gauges, both oil temp and trans temp would hit 240. This is climbing a hill pulling a three horse slant. It would stay low until there wasn't enough power to pull the grade in high gear. As soon as she downshifted, temps climbed. Once i would crest the hill, temps would come back down considerably.

Needless to say, I think those temps are a little high. Mine is getting a few more goodies to cool both when the trans goes back in. And yes, the trans did go. Blown o-ring on a servo. Resulted in burnt up clutches. But on that trip I was running a performance chip, larger turbo etc. So it's hard to pinpoint what caused it.

Waldo