Fluid weights and handling characteristics

This may be a stupid question, but do different fluid weights in the diffs / transfer case affect power transfer and steering performance like they do in RC cars?

I would imagine the weight of the truck would overcome any noticeable changes in handling from small / incremental changes in fluid weights, but as an RC nerd, this question has been bugging me!

Any insight appreciated!

 

Imagine stirring a bowl of water vs a bowl of honey.

Also imagine drinking water thru a straw vs drinking honey thru a straw.

Yes, the fluid weight would have an effect. But maybe not noticeable, it just depends.

 

I wonder what the % in weight change would need to be to affect the performance, and in what real-world applications it might make sense?

For instance, with my Tekno buggy, they say the following about center diff / transfer case fluid:
Thicker center diff oil mostly increases the power to the rear more than the front. Typically a balance is achievable to have the front and rear end of the vehicle powered the same, however sometimes you want the vehicle to drive from the front more than the rear and this is the case when you would want a thinner center diff oil to increase the drive of the front end of the vehicle.

Wondering if anyone's played around with this for a specific application.

 

If your talking having a thick enough fluid to induce a limited slip effect like you would do in an RC car no, you would severely impact fuel economy and performance if you had that thick of gear oil in there.


On RC cars (at least any I have seen) the oil is contained only in the case with the spider gears, the ring and pinion gears are dry or have just a light coating of grease. Therefore you can increase or decrease the weight of the fluid in the center case to increase or decrease the limited slip effect without affecting the resistance on the ring and pinion gears.

On an automotive differential all the gears share the same fluid so increasing the weight of it would increase drag on the entire assembly which would negatively impact fuel economy and performance.

 

I didn't think about the gears that were in contact with fluid vs those that are not. That makes total sense - thanks @Dm93