NV4500 fill plug thread and pitch

[AH64ID]

If you look at the sensor location and ring gear rotation it's not an extreme situation where fluid flings against it, it's all the time. 

 

While fluid will be splashing around inside the NV4500 I do not for a second think it will be anything like the rear end. The placement would have to be perfect to get slung fluid on it. No the temp of the fluid will not change enough to be of concern, it's simply a matter of proper slinging volume. 

 

3rd gear will provide more heat from gearing reduction; however, there is a lot lower power requirement at "in town" speeds from the reduction in speed, drag, and thus the torque input from the gearing reduction. It's not just like 5th gear (OD). In 5th gear the engine must produce more torque to get the same rear wheel torque and your torque requirement is much higher based on speed and drag. 3rd gear in town is not the same. To me it makes a lot more sense that the lower speed reduces slinging which increase the fluid level and the slightly overfilled trans now has more fluid on the sender and starts to provide a more accurate reading. 

 

Arbitray numbers and assuming wheel torque requirement is same in 3rd and 5th, which it wouldn't be in real life assuming level ground. 

 

1,000 lb/ft to the rear needs 1333 from the engine in 5th but only 598 from the engine in 3rd. The heat generated by 3rd is going to less than the heat generated in 5th. 

 

If your temps on the opposite side and in a cooler are about what he is seeing then it adds to my thought that he is reading low. Your temps should always be lower than his for a given gear/load/speed. 

Edited May 14, 2016 by AH64ID

[dripley]

Sure am learning a lot on this thread. I have never paid a lot of attention when in lower gears while towing because I am very seldom in that situation. Since I saw a lower temp in 5th versus 6th I thought that would continue down thru the gears, to a point anyway. Unless I get stuck in traffic, 1st, 2nd and 3rd just get me moving. 4th will get me thru most any town that I might happen to go thru. Most of the places I am going to are not to far off the beaten path. If not near and interstate I am near a good secondary road. Next trip I will have to pay a little better attention. My recollection is of the temps going lower even in 4th but by that time I moving in traffic and paying more attention to what going on outside the cab than inside the cab.