Savage X Diff Leaking

[xXPsycoCobraXx]

Hello I am having issues with my diff leaking silicone oil. I fill it so the gears are covered leaving a gap at the top. After a while the oil has leaked out through the shaft input. It has all the o rings installed.

Can anyone help or shall I just switch it out for grease? If so which grease as Z164 is no longer available

Thank you

 

[Gazzman]

Hello I am having issues with my diff leaking silicone oil. I fill it so the gears are covered leaving a gap at the top. After a while the oil has leaked out through the shaft input. It has all the o rings installed.

Can anyone help or shall I just switch it out for grease? If so which grease as Z164 is no longer available

Thank you

What wt oil are you using in them?

 

[xXPsycoCobraXx]

10K diff oil from CLM

 

[Gazzman]

Does seem abit thin, I use grease myself but you find peps on here and other forums say 50k.

 

[xXPsycoCobraXx]

I was going to use grease but people were saying that the grease won't coat or perform aswell as diff oil. I'm just concerned if I put thicker weight that that is just going to leak

 

[Mvtepixels]

How old are those o-rings? Sometimes new o-rings will stop the leaking. Are the diff shafts original hpi ones? Sometimes AliExpress and other aftermarket shafts are not perfectly round, making a bad seal with the o-ring. I like to use 200k oil on my diffs, for now I don't have leaks, but it's not 100% guaranteed 200k will fix your problem... if you don't want diff oil, lithium grease is the way to go... I use this grease on my bevel and input gears, very good stuff

 

[xXPsycoCobraXx]

This stuff stick to the bevel gears OK? I may go down the grease route

 

[Mvtepixels]

This stuff stick to the bevel gears OK? I may go down the grease route

Yes, this one is very viscous, ideal for metal stuff, ball bearings and other applications. Some lithium greases tend to be watery, it's those you need to avoid

 

[guinnessdublin]

That’s the beauty of this hobby guys trying in this case different diff weights or grease & experiment to see what works for you, nothing is set in stone!

 

[Gazzman]

At the end of the day the savage diffs come from HPI with grease in them for a reason. This is that what HPI designed them to have in them and not oil. If you can get oil to stay in these diff then that's great. but they need to be metal cases with good or new seals and the output shafts need to be shimmed correctly to keep a good seal between the O rings & the 2 large bevel gears. These diff leak oil as most people just change grease for oil with no thought of the O rings on the output cups, these are just standard rubber O rings and go hard quite quickly due to the heat that is generated by the friction by the rotation of the cup. Anytime I have had to rebuild a diff the 1st thing I notice is the hardness of the seals(O rings) and the fact that they deform( flatten off). which reduces there thickness and thus reduces there ability to seal.
Next time you have a shock apart to change the O ring in the cap look at the way it has formed itself to shape the cap, same with the diff O rings.
Yes new O rings may still leak abit as do shocks but won't be anything worth worrying about, it's just the nature of the product.

 

[coldsavage]

I've found What works best for me is grease and add a little silicone oil, usually 10k. That makes the grease almost fluid like to keep it from drying up and sticking on the edges and keeps everything lubricated well but stays thick enough to not leak out of diffs. Ive been doing this for years with great results on mutiple 4x4 rigs from short course to buggy to touring cars etc. I recently got a 2nd hand neglected savage I'm rebuilding and just rebuilt the diffs and I agree the o rings don't seal very well on these diffs compared to others. They need to be a tiny bit bigger in OD and thickness to seal oil in well.
Tldr; Go with Grease and a touch of oil to keep everything wet. I just use a premium synthetic moly grease, buy a tube and you have enough for life.

 

[xXPsycoCobraXx]

What's the best way to mix it?

 

[Gazzman]

What's the best way to mix it?

Well I don't really mix it, I just add 3-4mm of oil to the cases then pack them out with grease and let the rotation of the gears do the mixing, don't know if that's the right way but works for me.