NV5600 Temperature Question

[TylerMartin]

The other night I changed the engine oil in my truck and just happened to touch the transmission while I was under there. It was quite hot (almost too hot to hold my hand to it). Prior to the oil change I had driven about 100 miles (empty) at an average speed of 65 mph. The truck had been parked for about an hour and a half prior to changing the oil. I checked the fluid (still original) levels and color of the transmission oil and all appeared to be ok. I have a little over 30k on the truck.



Is this heat retention normal or could it be an indicator of something wrong? I haven't had any trouble with the transmission other than stiff shifting once in a while. It just seemed to be really warm considering it had been sitting for such a long time and it's something I've never really noticed before. Thanks for the help.

 

[Mad Bomber]

I have seen 180* on a hot day towing. Empty around town 120 or so

 

[JohnnyH]

Mine get very hot to the touch as well. I would say normal.

 

[Scrappy]

that trans case is a rather LARGE piece of cast iron, it is going to hold the heat in for a long time.

 

[Kirwin]

NV 5600 Temps

On both my trucks the NV 5600 runs about engine temperature after towing for an hour or so at freeway speeds. Towing on a hot day it can get in the 220 F range. Transfer case runs 10 to 30 F cooler than the transmission. Non towing it may take several hours to get to engine temperature depending on ambient temperature, but the engine actually cools faster after shutdown. I believe this is do to is increased surface area including all the accessories on the engine. By the way the differential gets to 150 F pretty fast at freeway speeds and also can get to over 220 F towing on a hot day. Still have no data on the front differential on either truck as I haven't figured out how to get a temperature sensor in there yet. Ken Irwin

 

[rbattelle]

I learned recently that "too hot to hold my hand on" is 137 degrees farenheit, give or take a few degrees.



I took some time this past Friday to stick a thermocouple on some components that I thought still felt "hot": front and rear differentials and the oil pan. All of them were below 130 degrees.



My point is, I don't think the human hand is a good measure of whether something is getting "too hot". Also, I agree with the others that 400 lb of NV5600 will soak up a lot of heat from the engine and will take some time to cool off.



I've attached a plot of temperature on the intake manifold. Time started while the engine was still running. It was shut off after about 1 minute. This should give you some idea where the excess heat comes from after you've parked the vehicle. Note the plot covers 75 minutes of data. Hood was closed during this experiment.



#ad




[That's odd... the image appears as a link to another thread instead of the acutal image... why?]

-Ryan

 

[TylerMartin]

Thanks for the input. It makes sense that the transmission would take a while to dissipate heat. I guess I was just a little surprised at how long it actually does take! Thanks again.

 

[Radshooter]

Does all this mean that we should be running temp guages on the NV5600 if we tow heavy? How hot it too hot? How many of you already have the temp guage on the manual transmission? What temps are you seeing?



Thanks...

worrywart Steve

 

[rbattelle]

Does all this mean that we should be running temp guages on the NV5600 if we tow heavy? How hot it too hot? How many of you already have the temp guage on the manual transmission? What temps are you seeing?



Thanks...

worrywart Steve

Dear Worrywart,



Nah, there's no need to run a temperature gauge on the NV5600 except out of pure curiosity. I doubt the transmission would ever "overheat". I'd invest in a set of Fastcoolers before investing in a temperature gauge.



Your Fellow Worrywart,

Ryan

 

[Mad Bomber]

Dear Worrywart,



Nah, there's no need to run a temperature gauge on the NV5600 except out of pure curiosity. I doubt the transmission would ever "overheat". I'd invest in a set of Fastcoolers before investing in a temperature gauge.



Your Fellow Worrywart,

Ryan

They are there and have a port for a gauge that's why I have a twin gauge and also in my diff cover too :-laf

 

[rbattelle]

They are there and have a port for a gauge that's why I have a twin gauge and also in my diff cover too :-laf

Yeah, I assumed that's why you had the temperature port. I also have Fastcoolers and will eventually get a temperature gauge. Just for curiosity...



-Ryan

 

[robert4570]

Try toughing the rear end next after a long drive. Talk about hot.

 

[Mad Bomber]

Yeah, I assumed that's why you had the temperature port. I also have Fastcoolers and will eventually get a temperature gauge. Just for curiosity...



-Ryan

I put a Westach duel gauge in the whole where the heated seat button is.

http://www.nwbombers.com/cgi-bin/forum/ikonboard.cgi?;act=ST;f=20;t=10468;st=16

 

[dgieson]

I have seen a temp in the trans of 250* on a day with 90* air temp and grossing a combined weight of 23k. The rear diff at the same time was 195* front diff and transfer case were both about 175*. Engine temp was 205* with an engine oil temp of 225*. These reading were after a 4 hour 70mph run on the interstate. I did not have fast coolers at that time.

Dave

 

[Fast 1]

dgieson temps that he quoted are exactly right. That's what mine was before I had fast coolers. With coolers the temps are reduced about 30 degree.



www.fastcoolers.com



Verlyn Fast

 

[Cryppie]

I'm an advocate of the Department of Redundancy Department... FAST Coolers and a temp gauge With Pennzoil Synchromesh, I saw upwards of 220 towing heaving (14k trailer) in hot (90 degree) weather WITH FAST Coolers. I've since switched to Amsoil Series 3000 (just before the new stuff came out), and immediately noticed a 20+ degree drop in temp running empty. Will be interesting to see how it is towing again... but since I'm out to sea right now that will have to wait a bit.

 

[griggsd]

Rather than mess around with a trans temp guage, you may want to get an infrared thermometer from Sears ($25) and point it at the transmission to guage temp as the mood strikes. It comes with a laser pointer so you know exactly where it's sensing. I use it check pumpkin/trans/xfer case when towing. Very useful tool.

 

[Mad Bomber]

Rather than mess around with a trans temp guage, you may want to get an infrared thermometer from Sears ($25) and point it at the transmission to guage temp as the mood strikes. It comes with a laser pointer so you know exactly where it's sensing. I use it check pumpkin/trans/xfer case when towing. Very useful tool.

But yhat's hard to do at 60+ MPH :-laf

 

[Buffalo]

Do these temperatures, that you guys are experiencing, seem to be higher than the trans. & diff. lubes can handle?



I've often wondered about these temps. since I live in the desert & there is a fair amount of mountain climbing, here. I usually climb more than 8000' in 230 miles with my 7200 lb. trailer, in tow. I would imagine that's pretty hard on the gear oils.



I'd appreciate hearing your thoughts and opinions.



Thanks.



Joe F. (Buffalo)

 

[Mad Bomber]

Do these temperatures, that you guys are experiencing, seem to be higher than the trans. & diff. lubes can handle?



I've often wondered about these temps. since I live in the desert & there is a fair amount of mountain climbing, here. I usually climb more than 8000' in 230 miles with my 7200 lb. trailer, in tow. I would imagine that's pretty hard on the gear oils.



I'd appreciate hearing your thoughts and opinions.



Thanks.



Joe F. (Buffalo)

If your thinking of a auto some of these temps are killer to them. This is also one of the reasons I've added the diff pan and trans coolers.