I'm planning to change my diff fluid to Redline. On the redline website it say no additional friction modifiers needed (even though they sell their own branded friction modifier).

Does anyone have any experience with Redline without the modifier?

Thanks

 

DTE the builder of my differential recommended Redline 75/140. Which has the anti slip added.

NOT SUGGESTING YOU USE THE 75/140 viscosity but I experience no problems with the self contained formula with their anti slip additive.

I THINK YOU WOULD BE WISE TO USE THEIR FORMULA WITH THE MODIFIER.

No experience without the additive other than what I have read.

 

Many of us are sticking to the OEM fluid. The latest version is fully synthetic, and it seems to be the best alternative since it has just the right amount of friction modifier. I'm in the middle of changing all fluids on my 3K-mile car. Am switching to Amsoil in the tranny, and sticking with Mobil1 5w30 for the engine. Good luck.

 

I just put the Redline 75W90 in my diff a few weeks ago and it works great!! I didnt add any additional modifier either, because it is already in the fluid.

On a side note, I dont like their ATF trans fluid in my manual, its a little notchy when cold (But fine when warmed a bit).

 

I don't have any personal experience with the Red Line with additive (nor do I have a C6), but this may help.

Most diff fluids today, including AMSOIL's and Red Line's, have friction modifier in them (though Red Line does offer both - so make sure you get the right one). For older diffs like those in the C5/C5 Z06 this additive level was sufficient to prevent diff chatter. Not so for the C6. For reasons I do not know, GM changed the characteristics of the C6 diff and it is much more prone to diff chatter. Many TSBs on this. Forced GM to come out with a new fluid (Dexron LS) with lots of additive. Though many prefer the GM fluid, many also report that the chatter comes back with the Dexron LS (possibly due to viscosity shear down of the basestock). Higher quality basestocks like that found in AMSOIL and Red Line will not be as prone to viscosity shear down as the Dexron LS, but they still seem to need more additive than comes in the bottle.

For my AMSOIL customers, I recommend adding at least a few ounces of AMSOIL's Slip Lock additive for the C6 diff.

In your case, there is nothing wrong with trying it and seeing what happens. Diff chatter will not harm the diff. If you use it without extra additive, and after a few k miles the diff does chatter, it is relatively easy to pop open the diff fill plug and squirt in a few ounces of additive. No need to drain the diff for a few ounces. Not sure about Red Lines additive, but AMSOIL's comes in a 4 oz bottle with a long squirt tip on it, so this is very easy to do.

 

Redline 75W90 in my car for over 2 years now, everything is good. No chatter at all.

 

I did it with modifier becasue I did not know better. Redline has or did kit available for sepcific cars and mine was one of them and it came with the modifier, so I put it in.

 

I changed to Redline without the additional since '09 on my LS2. No problems!

Redline motor oil at Amazon is $10.71/Q with Super Saver Shipping along with their other products - even for Hawaii.

For shipping dependency here in Hawaii, Amazon is hard to beat!