Have a couple questions here,
1st.
Where is the best place to install a transmission tempurature sensor-since mine has none, it's a turbo 400 transmission on a 89 gmc 3500 dually. and what kind of tempurature should it run and at what temp would be getting to hot and risk damage. I purchased a temp gauge and sensor and was told to T it in where the transmission cooler line comes from the transmission. Would that be a good place.
2nd.
Have a 4l60e transmission in other truck. Transmission was whinning when trying to get going at first in forward or reverse. Sounds like a spinning metal against metal sound. I took the truck to place i had the turbo 400 rebuilt, and changed fluid, it was burnt, and he said the filter had colapsed. Said it will need to be rebuilt in time. Was some metal shavings in pan. He put new fluid in and filter. Transmission is much better, but still makes some noise when first getting going in forward or reverse. Should i continue to drive it. Could i be doing more damage. Is there a possibility of anything that would be a proper fix without rebuilding it? Don't know much about transmission, but sounds to me like a band. If so would the same band slip in both 1st and reverse? Only does it when you first try to get the truck in motion, or when sitting still like at a stop light.
Any thoughts on these 2 questions would be greatly appreciated.
Thanks

Place the temp sensor in the oil line going into the transmission oil cooler and not out. That way you know how hot the transmission is actually getting and not the cooled transmission fluid going back. Use a infrared temp gun while the engine is at idle and someone has the vehicle in drive with the foot on the brake and the transmission in drive.

Take it back to the rebuilder and talk to him.

Thanks for reply, Thats where i was planning on putting the sensor. for the turbo 400

About the 4l60e, any other input on that, should i continue to drive it or may i do more damage. Transmission guy said drive it until it fails, not sure i agree with that.

i think your transmission guy is giving you good advice on the 4l60. the whining noise was very liekly caused by collapsed filter which would cause fluid starvation the basically the entire tranny. liek anywhere else fluid starvation causes wear. your tranny pump probably suffered the worst damage from this because it is spinning at engine speed all the time. most lieky the metal shavings in the pan are from the bushings in the tranny and probably the pump housing also. it is going to need a complete overhaul at some point probably needing a new pump and most if not all of the bushings as well. the noise you hear is likely from excessive clearance in the pump. if i were you i would run it till it didnt go any more. if you want more in depth info or anything pm me, im an ATRA (Automatic Transmission Rebuilders Association) certified tranny tech

Thanks again for the reply. Just wanted to ask, if it is the pump and or bushings that are going bad, could that wear into the case and cause me to have to end up replacing that and everything being much more expensive then. Would it be better to get it fixed now or soon instead of later?

I also wonder, why is it the noise only seems to be there when you first try to get it going in forward or reverse, but don't notice that it is able to be heard after you get it going with more momentum in forward anyway, don't notice that it disappears in reverse at all.

Thanks