Diff Fluid Options

[04BlackSRT10]

The time has come to change my rear diff fluid. The diff has been making some noise on the highway, and I'm hoping I can quiet it down with some superior fluid. I know some of you will say I'm an idiot to put anything but Amsoil Severe Gear in, but I'm also considering Redline Heavy Shockproof. I've read a lot about the Redline and most people seem to like it, but I'm wondering if anyone has put it in a Viper. I don't want to add anything that might mess up the diff more than it already is. Last time I changed the fluid there were small chunks of metal in it, so I know the diff already isn't at 100%.

[Steve M]

The time has come to change my rear diff fluid. The diff has been making some noise on the highway, and I'm hoping I can quiet it down with some superior fluid. I know some of you will say I'm an idiot to put anything but Amsoil Severe Gear in, but I'm also considering Redline Heavy Shockproof. I've read a lot about the Redline and most people seem to like it, but I'm wondering if anyone has put it in a Viper. I don't want to add anything that might mess up the diff more than it already is. Last time I changed the fluid there were small chunks of metal in it, so I know the diff already isn't at 100%.

If you are seeing metal chunks and it’s making noise, there’s a pretty good chance it needs rebuilt. Flex Tape won’t fix it, and neither will fresh fluid.

[13COBRA]

Rebuild or replace for sure.

The least of your worries will be messing it up with different fluid. It'll be long gone if you're driving it around with metal flakes in it.

[Old School]

The day I pulled the drain plug and saw metal flakes coming out was the day I started my search for a new diff....

[GTS Dean]

If you're trying to buy time while you budget and develop your ultimate rebuild strategy, a drain & solvent flush prior to new HD fluid is a good idea. You need to be vigilant for any sudden worsening of symptoms - noise or vibration. And obviously, don't flog it.

[04BlackSRT10]

I'm thinking I might want to go with a Wavetrac if I need to rebuild the diff. Either that or get some 3.55 gears, which I've been planning to do at some point anyway.

[Steve M]

I'm thinking I might want to go with a Wavetrac if I need to rebuild the diff. Either that or get some 3.55 gears, which I've been planning to do at some point anyway.

3.55s with a Wavetrac would be my choice if I were in your position.

[Fatman2006]

I heard noises, and took it to a shop, they confirmed metal flakes. Installed Wavetrac with stock gear ratio.

Here's an excellent video if you want some more information on that new diff you're about to buy.

https://youtu.be/XuqdWkYiO-M

[Old School]

The metal flakes in my Gen3 were not from the ring and pinion, the gears looked good. I think the metal was from the spider gears internal to the Hydra-Lok.

[04BlackSRT10]

I pulled the oil again to check and see if there were still metal pieces, and indeed there were. One piece was clearly the tip of a gear tooth -- looks like its probably from a spider gear. I refilled the diff with AMSoil so at least I know a good quality fluid is in there while I wait to rebuilt it. I also did the trans fluid and luckily, that looked fine. AMSoil MTL went in this time and I can say that it definitely shifts smoother and just as easily as it did with the ATF+4 that was in it. The diff seems a littler quieter now too with the Severe Gear in it, so I guess I'm an AMSoil convert now haha.