Still Dont Understand Diffs Help Please

[xl3nt]

ok i have had my hyper 7 tq sport .21 for about 3 months now I'm getting the hang of things understanding more and more, but i still dont understand how diffs improve your performance iv read and read but i never get a straight answer all i wanna know is how do diffs improve your performace?
can someone help

 

[olds97_lss]

Do you understand their general function?

When you turn a corner, your inside tires rotate less than your outside tires. Without a diff, the outside tire would be drug along or the inside tire would be pushed along, both of which fighting to push the vehicle in a straight line.

Using different oil viscosities allows you to tune how much power is sent to the tire with the most traction. Normally, when you make a hard turn, the inside tires want to raise off the ground. When this happens, all the power goes to that tire, which is known as "diffing out" I believe. But, when you have a high weight oil in the diff, it will still diff out, but not as much. A larger percentage (compared to grease or no oil) of the torque is transferred to the tire that has the most grip, or in this case, the outside tire. This usually allows your vehicle to turn more aggressively.

I won't prattle on any longer with info you already know, if you already know.

I'm not a racer at all. I use diff oil to give me "limited slip positraction" like in 1:1 autos. When bashing, having larger percentages of power getting transferred to the tire always on the ground helps avoid getting high centered on things. I run 50K oil in my MT's compared to 3K,5K,8K that usually is ran in 1/8 buggy diffs.

 

[Runaway Jim]

Well, I assume you know that they're needed in order to have 4 wheel drive. Is your question more about diff oil rather than the diffs themselves. If so, and you're running a buggy you should check out some of the set up sheets for guys like Adam Drake. I have a Losi 8ight RTR and ran it for a while with the stock grease in the diffs. It sunk down a ton when I was really on the gas and the stearing was pretty all over the place. After changing the front center and rear diff oil it was a whole new ball game. I think I put 10K in the center, 7K in the front and 5K in the rear. The car had so much more traction, really pulled more with the front wheels in addition to being pushed by the rear. The steering was better because the diffs in the front had heavier weight oil in them and didn't spin independently of one another as they had in the past. It was like a completely different car. Well, hope this helps. If you haven't worked on the diff oil in your rig, try it out. It was a simple job for me to do and I'm relatively new to this stuff. It's a cheap upgrade but you won't find an upgrade that will make such a big impact on the drivability of your car...

 

[xl3nt]

thank you so much both of you i have a clear understanding of what diff oils and diffs do now 1 more question if its not too much how do i change/add diff oils do u know of any tutorials or anything thanks

 

[Amoeba]

I saw a very good tutorial but my google-fu is failing me. I'm sure someone can find the one I'm thinking of. Basically all you do is take the diff case apart to where you can see the gear & pinion similar to:

Fill the case with your chosen diff oil weight so that the oil just comes up to/almost covers where the gears cross. Close back up and you're good.

 

[ohmygahitscoby]

For ball differentials though, you have to tighten the screw that keeps both sides of the differential together.

 

[Amoeba]

Aha! I found it: https://www.rcnitrotalk.com/how-to-put-fluid-in-your-diffs/

Hope that helps.

 

[ajames942]

now i understand diffs too...thanks everyone!!

 

[RC Addict]

now i understand diffs too...thanks everyone!!

Postcount +1!

 

[xl3nt]

thanks alot now i just have to figure out how to take them out

 

[Amoeba]

thanks alot now i just have to figure out how to take them out

I usually show them a picture of McCain naked. Works every time.

 

[Runaway Jim]

It's really not a difficult job. When I did them on my 8ight it was the first time I'd ever done them on any RC. If your car came with an exploded view of everything in the directions, take a look at that before taking anything apart. Often times you'll actually need to unscrew less things than you expect to get to the diffs. I also took pictures with a digital camera of the first one I did as I took it apart, just in case I couldn't remember what was supposed to go where when I went to put it all together. Last thing, clean the original grease off of all the gears before putting the new oil in. Use an old tooth brush and a little brake or engine degreaser. That worked well for me. Rinse the degreaser off before reassembling and you'll be fine...

 

[olds97_lss]

Fill the case with your chosen diff oil weight so that the oil just comes up to/almost covers where the gears cross. Close back up and you're good.

Yep. If silicone oil is in yours now, take the time to clean them out really good with paper towels before refilling them with the oil you decide on. I have yet to find a solvent that will dissolve silicone oil though. Just paper towels and q-tips to get the corners clean.

Like Amoeba said, just fill it until the oil is level with the top of the x-pins that hold the spider gears in place. Over filling will just lead to a mess when you put it back together and the oil oozes out everywhere.