Onemoparnut

I picked up a factory limited slip for my truck but I haven't installed it yet. What is the best additive to use for the limited slip?

93flatbed

Before I switched to Royal Purple I would run General Motors additive in my diff. Now I don't worry about it with my fluid already having it in there.

Onemoparnut

Ok maybe I will change over to the royal purple I was thinking about doing that anyway. Where can I get it autozone maybe?

archer39

pepboys carries royal purple don't know about autozone. I am running kendall limited slip additive (what the local parts store carries) with no problems so far. No chatter and it grabs good.

Onemoparnut

Ok cool thanks I will try to pick it up tomorrow if they are open.

93flatbed

? I get mine free at my dealership. I'm sure most parts stores carry it. Don't know the price either, I'm sure it's not as cheap as some others out there.

Onemoparnut

What weight gear oil should I get?

JBradley500

if i recall correctly..

if you do any towing you probably should run 75/140 and synthetic if youre in a cold area.

75/90 if you use your truck as a commuter to help with milage.

archer39

75-90 is still synthetic. if the truck is just a daily driver and does not tow much then 80/90 is fine.

freight train

I know everyone has their own opinion. When I ordered my diff from Randy's ring and pinion they told me royal purple was a bad idea. They said it didnt work well with the clutch faces and caused premature wear or something like that. They recommend using a conventional gear oil. To each thier own though. RAM

archer39

Thats Pretty much why I am not running royal purple. I got there rebuild kit and that's what they told me also.

JBradley500

i dont see many reasons to run royal purple. a lot of issues have occurred. more hype than anything. i try to spend my synthetic oil money on redline oils.

Onemoparnut

Well I got royal purple on mine now we will see how of lasts.

MARF75

I was told synthetic is to slick and won't let new gears wear properly during break in

samiam4

There was a review paper compairing many diff oils. I think Amsoil came out on tops and Redline- heavy shockload was quite good. I run the Redline product in my Torsion-gleason diff with good results.

RP would be great as it has the additive in the fluid..